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Maintaining a low operating temperature through the use of a passive cooling system is one method of increasing the efficiency of a photovoltaic system. As temperatures rise, photovoltaic modules' performance declines. By attaching water flow inside copper and PVC pipe at the backside of the PV panel as a cooling device, this study investigates the effect on surface temperature reduction and voltage output of PV panel, with the goal of increasing and improving the effectiveness of electrical output by lowering the exterior surface temperature of the PV module. The experiment was carried out in Nagpur's steady environment with constant outside temperatures between 32 and 34 degrees Celsius. Using a data recorder, the panel's temperature and open-circuit voltage (VOC) were noted both before and after the cooling system was installed. To enable simultaneous recording of voltage and temperature data, the system was equipped with four thermocouples for each panel, as well as a voltage sensor, Pynorometer, anomometer. Solar irradiance ranging from 100 to 1000 W/m2, and non-uniform fluctuations in wind speed with a mean value of 1.5 m/s. The installation of the suggested cooling devices on the PV panel resulted in a surface temperature reduction of 4 o C or 7% and a voltage gain of 0.29 V or 2.8%, respectively. [ABSTRACT FROM AUTHOR]

Internal car air conditioning systems have been available for over 80 years. The use of self-cleaning technology to help reduce issues with dirt and frequent air conditioner cleaning has been applied to aid in maintaining the conditioning systems. However, in an automobile, implementation of this technology has not yet been done. Considering the current environmental conditions, with elevated levels of PM2.5 dust and air pollutants, car air conditioning systems need to expel heat to the condenser at the front of the car, which constantly encounters external air while the vehicle is in motion. This leads to the accumulation of dust particles, negatively impacting the efficiency of the cooling system. As a result, the air conditioning systems may take longer to cool or not cool effectively. Cleaning this system manually can be challenging and may cause damage to nearby components. To address this issue, the current research investigated an automatic car air conditioning cleaning system based on refrigeration principles. This cleaning system can extend the air conditioning system's lifespan by keeping it clean. Experiments were conducted by adding equipment to facilitate self-cleaning for both the evaporator and condenser. After installation, the temperatures were measured at various points. Results demonstrated that the evaporator's cooling efficiency improved by 59.08%, resulting in a cooling temperature decrease of 23.1 oC. Moreover, the maximum working temperature of the condenser, where it can expel heat effectively, improved by 16.13%, resulting in a temperature decrease of 10.9 oC. Data analysis from this experiment provided a proper method of maintenance for car cooling systems that produces energy savings and efficiency enhancement. This contributes to longer-lasting and more effective air conditioning systems for cars. [ABSTRACT FROM AUTHOR]

The paper presents Computation Fluid Dynamics (CFD) simulation of cooler system for small Li-Ion battery module suitable for electromobile's traction battery. The results from simulation show the difference in cooling effect for individual cells in terms of their different operation temperature. This difference in cells' temperature should be the input for further State of Charge (SOC) and State of Health (SOH) calculation and evaluation of battery module. [ABSTRACT FROM AUTHOR]

This paper reviews an innovative cooling system combining piezoelectric materials and nanofluids for high-performance computers. It explains the working principles of piezoelectric materials, detailing their context and construction, emphasizing the use of PZT lead zirconate titanate. The nanofluids, specifically Al2O3, enhance heat transfer efficiency. The construction of the piezoelectric micropump and methods for nanofluid preparation are outlined. The paper compares the advantages and drawbacks of nanofluids to traditional coolants, emphasizing stability challenges. It concludes by highlighting the potential of this integrated cooling system and suggesting areas for improvement. Overall, the proposed solution offers a promising avenue for enhancing electronic component cooling efficiency in compact systems. [ABSTRACT FROM AUTHOR]

The failure of the active cooling system in the accident case of the Fukushima Daiichi nuclear power plant has become a problem in developing a passive cooling system by utilizing the applicable natural laws. The natural circulation flowas the basis of the passive cooling principle is very dependent on the temperature or power parameters, as well as geometric parameters such as the total length of the pipe, diameter, and height difference between the cooling and heating sections. So that the phenomenon of changes in natural circulation flow rates in passive cooling systems based on geometric parameters innuclear reactor safety systems is an essential concern in similar research worldwide. This study aims to analyze changes in natural flow rate with water working fluid in laminar conditions based on geometric parameters with variations in temperaturedifferences on the hot and cold sides using the FASSIP-04 Rectangular Loop design. Research has been carried out using dataanalysis methods based on changes in geometric parameters (boundary conditions, BC) and operational parameters (initial conditions, IC). The analysis is based on 180 the amount of data generated based on calculations. The study shows that only the rectangular loop with a total length of eight meters has the optimum flow rate. The flow rate in the rectangular loop witha pipe diameter of 1 inch with a temperature difference between the cold side and the hot side of 70°C has a natural circulationflow rate of 0.76 m/s. A rectangular loop with a pipe diameter of 2 inches and a temperature difference between the cooler andheater areas of 80°C has a natural circulation flow rate of 0.87 m/s. On a 3-inch diameter loop, the temperature difference between the cold and hot sides is 80°C and has a natural circulation flow rate of 0.89 m/s. The difference in the natural circulation flow rate value based on the diameter of the 1-inch loop against the 2-inch loop is 14%, while the 2-inch loop against the 3-inch loop is 2%. So in this study, increasing the flow rate from a 2-inch diameter loop to a 3-inch loop is not toosignificant. However, a significant increase occurs in a 1-inch loop to a 2-inch loop. [ABSTRACT FROM AUTHOR]

Solar energy is one of the renewable energies that can be used as a source of electrical energy using Photovoltaic panels. However, there is a serious problem with Photovoltaic panels, namely the efficiency that decreases when the cell temperature is above the optimal working temperature, so it requires a method to control the cell temperature. One cooling method that can be applied is the water spray system. In the water spray cooling system, many parameters that must be adjusted to produce optimal cooling performance. One of the important parameters that must be paid attention to is the nozzle component. This paper summarizes the configuration of the nozzle components in the water spray cooling system for their cooling performance and the results of power output and efficiency of photovoltaic panels. The result obtained is that the cooling method with a water spray system can optimize the results of power output and the efficiency of photovoltaic panels. Each type and characteristic of the nozzle has a different cooling performance which will be explained further in this paper. More research on the water spray cooling system on photovoltaic panels is still needed to get good cooling performance results and optimize the efficiency of photovoltaic panels. [ABSTRACT FROM AUTHOR]

The efficiency of the PV system decreases when there is an increase in the temperature of the module cells due to high solar radiation. This can be overcome by adding fins on the back of the PV module as a cooler. This study aims to compare the use of linear (conventional) fins with lapping fins based on thermal performance analysis. Parameter study based on wind speed and solar radiation. Thermal performance analysis using computational fluids dynamic with Ansys fluent. The test procedure is carried out by simulation including making linear (conventional) and linear lapping fin geometries, conducting mesh quality studies, and determining boundary conditions and modelling parameters. From the results of the study, it was found that the temperature decrease of the PV module with lapping fin with a temperature difference of around 6.77°C (14.4%) when compared without using fin (without heatsink), while 5.41°C (10.87%) compared to with conventional linear fins. The results of this study support the use of integrated PV and passive cooling systems to reduce efficiency losses under actual conditions, where solar radiation varies over time, which may be unfavourable for conventional heatsinks. [ABSTRACT FROM AUTHOR]

This study investigates the impact of outlet fan placements within a PC casing for effective CPU cooling. The objective is to compare and optimize the cooling performance of the system and minimize the risk of thermal stress on the electric components inside the enclosure. Computational fluid dynamics (CFD) simulations are utilized to analyze the effects of outlet fan location, orientation, and quantity on the temperature distribution within the PC casing. The results demonstrate that the presence and placement of outlet fans have a significant effect on the cooling efficiency of the system. It is found that the most effective configuration involves having an exhaust or outlet fan to increase airflow velocity within the enclosure. This configuration, based on the venturi effect, evenly distributes airflow, increasing the flowrate and improving heat transfer rates through convection. However, certain outlet fan placements were found to reduce the cooling efficiency of the system. It was found that the best configuration was the 'front outlet fan' configuration whereby the lowest achieved average temperature for fluid, small chip volume, and main chip volume were 21.29°C, 38.86°C, and 51.37°C respectively. The study highlights the importance of optimizing fan placements and configurations specific to computer settings. By utilizing CFD simulations, a systematic analysis can be performed to understand and improve computer cooling systems. The findings of this study contribute to the overall understanding of computer cooling and provide valuable insights for the design and optimization of cooling systems. This research is significant for computer enthusiasts and manufacturers aiming to enhance the cooling performance and reliability of PCs. [ABSTRACT FROM AUTHOR]

Various types of cooling systems are widely used in Iraq to achieve comfortable conditions for occupants during the hot summer. Large amounts of energy are consumed due to the use of cooling systems in buildings for various activities. Improving the coefficient of performance for HVAC systems is an essential priority within sustainable energy management strategies. In the present paper, an experimental study was carried out to determine the effect of cooling the condenser in a split unit type air conditioner with a capacity of (1 refrigeration ton) indirectly through the passage of air over a wet filling. A different thickness of pads (3, 5 and 7 cm) was used. The pad was moistened with water at different volume flow rates ranging from (100, 125, and 150) liters / h. The rate of airflow passing through the condenser was fixed to determine the refrigeration system's performance and the energy consumed compared to the reference case at different factors. The results showed that the best increase in the coefficient of performance of the system is (25.2%) when the thickness of the pad is (5 cm) and volume flow rate (100) liters / h, and the percentage of energy saving is 13.2%. [ABSTRACT FROM AUTHOR]

To improve the performance of an air-conditioning system (A/C) in sub-tropical climates This paper presents an experimental study by studying the double effect of indirect evaporative cooling integrated with heat pipe heat exchanger (HPHE) on sensible heat recovery as well as the coefficient of performance (COP). In this study, HPHE was used consisting of two rows of copper tubes with a diameter of 0.014 m, and length of the evaporator is 0.3 m, the condenser is 0.3 m and the adiabatic is 0.15 m. The results showed that the use of a heat pipe heat exchanger decrease the temperature of air inlet condenser of (A/C) system from (2-3) degree and improves the coefficient of performance by 10 % when compared to conventional cooling systems. HPHE filled with acetone with filling rate of 70%. [ABSTRACT FROM AUTHOR]

The transition toward electric vehicles (EVs) powered by lithium-ion batteries (LIBs) has gained momentum due to their potential to reduce fossil fuel dependence and mitigate environmental impacts. However, the thermal management of LIBs remains a critical challenge affecting their efficiency, longevity, and safety. In this study, we employ ANSYS numerical simulation software to investigate the thermal behaviour of pouch-type LIBs used in commercial applications under various discharge rates. To analyze thermal behaviour, we utilize the empirical model proposed by the Multi-Scale Multi-Dimensional (MSMD) group's researchers Newman, Tiedemann, Gu, and Kim. The simulations are carried out at different C-rates (1C, 2C, 3C, 4C, 5C, 10C, and 15C), and detailed contour plots of phase potential for both negative and positive tabs are presented. Our results indicate that the battery's maximum surface temperature is directly related to the discharge rate, with higher C-rates leading to elevated temperatures. To address this thermal issue and enhance discharge capacity, we introduce a water-based liquid cooling system and evaluate its effectiveness in reducing the maximum cell surface temperature. This study plays a pivotal role in advancing the development of innovative cooling systems for LIBs, with the aim of optimizing battery performance and ensuring safe operation. As the electric vehicle industry continues to grow, addressing thermal management challenges will be paramount in achieving sustainable and efficient EV technologies. [ABSTRACT FROM AUTHOR]

The emerging field of Fractals which has its background from Mathematics is also having a wide contribution in the fields of Theoretical Physics as well as Engineering and Technology. The proposed study is a genuine try in having a thorough discussion of existing Fractals for their various geometrical aspects as well as will focus on trying developing a new unique Fractal. Also, the study will extend towards the applications of Fractals in varied sense like Fractals based antenna designs, cooling systems etc. [ABSTRACT FROM AUTHOR]

With the rapid development of modern science and technology, people's lifestyle is gradually developing in the trend of intelligence and automation, and the emergence and development of smart homes is part of making life more comfortable. This research explores into the synergy between environmental awareness and automated control systems, aiming to create comfortable, sustainable, and energy-saving living environments. The study investigates various sensors, such as temperature, humidity, access control, and light sensors. By designing closed-loop systems with these sensors, different controllers like proportional-integral-derivative (PID) controllers, and other components, the lighting, heating, and cooling systems can automatically adjust due to changes in environmental conditions and user preferences through feedback signal of the system. These systems play a great role in the further development of smart homes, not only improve the quality of people's daily life, but also improve the safety and privacy of the living environment, and the wide application in different industries has also promoted the development of society. [ABSTRACT FROM AUTHOR]

At present, our country does not have an effective programme for the organization of water-chemical regimes of circulating refrigeration systems, solving three problems at the same time: the prevention of sedimentation, Reduction of corrosion rates of copper-based construction materials and avoidance of biological growth within the system and on heating surfaces. In addition, the influence of cooling water quality on the corrosion of copper-containing alloys in high-inertial water cooling systems of turbine condensers has also been largely unknown. The use of film-forming amines (in particular, chelamine and octadesilamine) is a promising method to address this problem, but information on this issue is scarce. Therefore, it is essential to optimize the water-chemical modes of recycling cooling systems of turbine condensers in order to reduce the corrosion rate of brass. Thus, the aim of the work is to study the influence of the quality of cooling water and corrective reagents on the corrosion rate of brass in order to optimize the water-chemical modes of cooling systems of turbine condensers. [ABSTRACT FROM AUTHOR]

Regenerative heat exchangers are widely used in life support systems, gas turbines, boilers and other high-temperature industrial installations. These heat exchangers are used for cooling and heating gases, humidification and dehumidification of gases, heat recovery from high-potential heat carriers. Today, the increase in energy consumption and the increase in energy prices require a large-scale energy-saving policy in the creation of modern engineering structures-residential, commercial and industrial facilities alike. When designing and creating life support systems to save energy, it is advisable to use secondary energy resources, such as, for example, the heat of the air removed from the room. The energy intensity of conventional ventilation systems is on average 50-80% of the total energy intensity of the engineering systems of the facility where they are operated. The use of rotating regenerative heat exchangers in ventilation and air conditioning systems makes it possible to return up to 85% of heat to the system at a relatively low capital investment. In this regard, when improving such systems, considerable attention should be paid to the calculation, optimization and increase in the efficiency of heat exchangers. Thus, this work is about increasing the efficiency of rotating regenerative heat exchangers in ventilation and air conditioning systems. [ABSTRACT FROM AUTHOR]

In thermal power plants in Uzbekistan, the drainless recycling cooling system is widespread, in which water of the most favorable and constant quality and heated in the condenser turbines are used in the water treatment plant thermal power plant. Since the recycling cooling system uses technical raw water, low solubility deposits (scale) are formed on heat exchange surfaces in turbine capacitors. It is believed that the cause of precipitation is the concentration of low soluble water components by evaporation of water in cooling towers. Due to the low thermal conductivity of the deposits formed on the heat exchange surface of the capacitors, the temperature pressure increases. As is known from the scientific and technical literature, the pressure in the turbine capacitors depends on the contamination of the cooling surface. Because of this, the vacuum worsens. The deterioration of the vacuum leads to an over-consumption of steam. Thus, the aim of this work is to increase the operational efficiency of the recycling cooling system of the thermal power plant. [ABSTRACT FROM AUTHOR]

In this article, based on the cooling system with Polycarbonate and Aluminum channels, maintaining the efficiency of the solar panel and heating the water with excess heat in it is considered through mathematical modeling. Taking into account the number of solar elements, the length of the channel, the temperature change of the solar panel and water over time at different values of 0.002-0.004 m/s of the speed of the water entering the channels of the cooling system was analyzed. The calculations assumed that the device was placed in the sun at 10:00 AM and the initial inlet water temperature was 25°C, and the duration of the calculation was taken from 10:00 AM to 8:00 PM. [ABSTRACT FROM AUTHOR]

The performance of evaporative cooling systems depend strongly on the relative humidity of the inlet air. Therefore, it is crucial to reduce the inlet air humidity ratio, and one of the solutions to regulate this ratio is using desiccant material. In this paper, a practical study of an evaporative cooling system was conducted and a dehumidification unit was constructed that consists of a (fin-tube) heat exchanger covered with silica gel to overcome the sensible and latent load. The heat exchanger is connected with an evaporative cooling system and a heat recovery unit as an indirect cooling stage. The cold water in the evaporative basin is utilized for precooling the inlet air. Furthermore, using the cold water of the evaporative basin can reduce the heat released during the removal of moisture from the air (adsorption process). Hot water from a heat source (electrical heater) was used to regeneration the desiccant. The effects of the external conditions (temperatures and humidity) on the system performance were studied. In addition, the effect of inlet air velocity, hot water flow rate, and the time required to complete the cycle on the performance were evaluated. It was found that the desiccant material can be regenerated at a temperature between 45-65 °C and the supply air temperature to the zone of 25 °C when the airflow is 0.48 m3/s. The system can work in hot and humid places. [ABSTRACT FROM AUTHOR]

In order to enhance the efficiency of the photovoltaic module, a sun concentration and cooling technique is being used in this research. Standard polycrystalline photovoltaic module, photovoltaic module with active cooling system as well as concentrated photovoltaic (C-PV module) and a cooling C-PV system were used in the experiments. On the 5th and 6th of November, the experiments were carried out in Baghdad, Iraq. The photovoltaic panel's frontal water flow serves as the cooling system using evaporative cooling. When compared to a standard PV module, the average power output and maximum power output from the C-PV system is increased by 23.6% and 28.3%. Furthermore, the C-PV system and the C-PV system with cooling technique have an average increase in electrical efficiency of 7 percent and 9 percent, respectively. In comparison to the other three configurations, the C-PV with the cooling system produced significantly more energy. [ABSTRACT FROM AUTHOR]

Cooling fluids are fluids that function to remove heat from certain object. In this paper, different cooling fluids were used to cool down the temperature of solar panel. The main objective is to investigate the effects of different type of working fluid on the cooling performance of the solar panel. The cooling fluids that have been used are water, ethylene glycol and mixture of ethylene glycol and water. These different cooling fluids will be used to determine the effects to the solar panel temperature, the power output of solar panel temperature and the efficiency of the cooling fluids on cooling performance. In this research work, the power output of the solar panel is the parameter that determines the cooling performance of working fluids. Longer cooling time of the solar panel shows a significant increase in solar panel power output. The findings revealed that the solar panel power output has achieved the highest efficiency at 8.18% when the water is introduced as cooling fluid compared to ethylene glycol at 3.18% efficiency and mixture of water and ethylene glycol at 1.91% efficiency. [ABSTRACT FROM AUTHOR]

Indonesia has the largest geothermal potential in the world, recently Indonesia only utilizes 7% of their geothermal to generate electricity. To increase the electricity production, the development of new geothermal power plant is needed, also the optimization of existing geothermal power plant. There are several types of geothermal powerplant system, depends on steam condition and utilization. This paper aimed to analyze the heat loss occurred in geothermal powerplant system X, also compare the cooling system between direct contact condenser (DCC) and indirect contact condenser (ICC). The comparison study has been simulated by using ASPEN HYSIS software. The method used to analyze the heat loss was by calculating exergy in each stream, so that we can calculate the exergy destruction at each process equipment. The result shows that the turbine produced 60 MW of electricity and largest heat loss occur on cooling tower with percentage about 17.64% for ICC system and 18.41% for DCC. [ABSTRACT FROM AUTHOR]

We investigated free convective heat transfer within an electronics cooling system with a metallic porous extension. The finite element method is used to solve the associated transport equations. Changing fluidic and geometric parameters allows examination of the isotherm contour, streamlines, and heater average temperature. It is found that the presence of a metallic porous block causes higher temperature up to a greater height of the domain than the absence of a porous material. The strength of the vortex is greater in the case of porous extension than in the case of no extension. Furthermore, the effect of Darcy number (Da) on average heater temperature (θavg) is negligible. The value of θavg decreases as the height of the porous extension increases. Inferences obtained from this analysis are expected to provide an adequate basis for the effective design of small-scale thermal management devices/systems that are typically used in electronic cooling systems. [ABSTRACT FROM AUTHOR]

Chemotherapy, a medical procedure used to treat cancer, may result in partial or complete hair loss (alopecia) side effects. It heightens psychological pain, which might lead some patients to decline therapy. Chemotherapy effects on the hair follicles. This paper aims to develop and produce scalp cooling systems that are equipped with sensors for better control to prevent hair loss in cancer patients, the approach involves reducing scalp temperatures to minimize blood flow to the scalp area before, during, and after chemotherapy. The Peltier and a radiator are used in place of the compressor and condenser in the cooling system to turn from mechanic to electronic, which was a new idea because no one had previously used a Peltier to manufacture the device, so explain the cooling system is designed and fabricated for production and display the circulating coolant through Peltier who responsible on the cooling entire scalp area. The system consists of two main components: the cap part and the cooling part. The components of the cap are the cap is comprised of several components, including an inner silicone layer, an aluminum cover, and an insulated cap cover. On the other hand, the cooling system consists of various elements such as a microcontroller, smart touch screen, voltage step-down module, power supply, fan, radiator, water pump, relay 1ch, and timer. It tested on many volunteers for almost an hour and then made the results as curves. The system was effectively implemented at a low cost, and the results demonstrate temperature levels within an acceptable range of (8-15) °C, which aligns with findings from previous studies. [ABSTRACT FROM AUTHOR]

A heat sink is a device that removes heat from electronic devices that consume electricity. This heat removal is required to meet the equipment's design requirements. In this paper, different heat sink geometries are designed and simulated using computational fluids dynamic software to compare the temperature distribution and thermal performance. The main objective is to investigate the effect of the fin arrangement, base plate thickness and type of heat sink material on the thermal performance of heat sinks using the Ansys FLUENT 2021. The heat sinks have been analyzed at different heat load supply of 60 W, 70 W and 80 W. Three different fins arrangement of rectangular plates, rectangular pins and separated short plates heat sink are compared of the thermal performance in this study. The effects of heat sink materials on thermal performance were also investigated numerically. In this research work, thermal resistance is the parameter that determines the thermal performance of the heat sinks. The findings revealed that the thermal resistance is lower for the copper rectangular plates heat sink with 5 mm base plate thickness. [ABSTRACT FROM AUTHOR]

This paper presents the desired characteristics of adsorbent and adsorbate in adsorption cooling system. The development of competitive market ready adsorption chiller is hindered by the physics of the adsorbent-adsorbate pairs, the main component of this cooling system. A breakthrough is required to produce adsorbent-adsorbate pairs with superior characteristics. The adsorbent-adsorbate pair must have low heat of adsorption compared to the latent heat of vaporization of refrigerant. The adsorbent uptake must be sensitive to its temperature, to reduce energy usage for sensible heating during transition from adsorption to desorption phase. An increase on the rate of adsorption and desorption must be accompanied by increase in rate of heat transfer to make sure optimum performance can be achieved. For a quick assessment on performance of adsorbent, refrigerant and heat exchange surface, adsorption calorimeter could be used. [ABSTRACT FROM AUTHOR]

Recently, the use of greenhouse is developing. Farming fruits and vegetables using a greenhouse can overcome the unpredictable climate. The plants that need specific air temperature and humidity could grow well inside a greenhouse. As a preliminary study, the effect of circulating water as a thin film at the outer surface of the greenhouse is observed. The water film is intended to cool the greenhouse. In this experiment, there are three models used. The first isthe greenhouse (called GH1) with cooling water flowing at the outer surface of greenhouse periodically. The second is a greenhouse (called GH2) without a cooling system and the third is in the open space or natural farming. A water sprayer is installed in each model to water the plants. It sprays periodically. In each greenhouse, three temperature and humidity loggers are installed to measure the air temperature and humidity. The loggers are installed in the middle of the greenhouses with some different heights from the plants. From the experimental results, the air temperature in the greenhouse GH1 decreased compared to the ambient temperature at position 3, while at GH 2 and open space farm N thetemperature increased at positions 1, 2, and 3. The average relative humidity was 72%, 68 %, and 47% at GH 1, GH 2, and open space farm (N). [ABSTRACT FROM AUTHOR]

This paper analyzes the performance of a water cooled chiller at various number of fan cooling tower under the constant cooling capacity. The nominal capacity of the water cooled chiller unit is 800.0 ton and the refrigerant is R-514A. The performance of the water cooled chiller system when using 6 fans with a COP of8.29 and a kW/TR value not exceeding the minimum value set under the ASHRAE standard of0.42. The largest energy consumption is generated when the system uses 3 fans which is 2513.58 kWh during the period of time the system is turned on (7 hours). While the lowest energy consumption is generated when the system uses 6 fans which is 2036.78 kWh during the period of time the system is turned on (7 hours). The percentage of energy consumption increase when using 6 fans to 5 fans by 12,78%, from 5 fans to 4 fans by 7.48 % and from 4 fans to 3 fans by I,79%. Based on the results of analysis of the use of fan cooling tower variations on the performance and energy consumption of water cooled chiller is best when using 6 fans. [ABSTRACT FROM AUTHOR]

NuScale is an integral pressurized water reactor (PWR) that applies natural circulation mechanism in its safety system. During a loss of coolant accident (LOCA), its emergency core cooling system (ECCS) uses the containment wall to cool the reactor core by opening valves. If the ECCS fails to function, one alternative to prevent the core damage is by utilizing the steam generator (SG) to remove heat from the primary system. In this study, a simulation is carried out to investigate whether the SG design has sufficient capacity for such cooling. The simulation is performed using the RELAP5 code by modeling the reactor system, safety system, and control system at the input. The model is validated using steady-state and transient calculation data from the NuScale design certification application (DCA) document and independent analyst publication. The scenario was a pipe break at the chemical and volume control system (CVCS) injection line, followed by failure of the ECCS. Activation of the SG feed water is carried out 10 minutes after the ECCS failure is recognized. The simulation result shows that the SG cooling is capable of bringing the pressure and temperature in the primary system down and maintain a stable water level at a position above the top active fuel. However, due to the limitation ofRELAP5 in modeling the helical SG, this simulation result needs further verification, especially in condensation cooling. [ABSTRACT FROM AUTHOR]

The accident at the nuclear power plant in Fukushima, Dai-ichi, Japan, proves the failure of an active cooling system that uses pumps. Thus, using a passive cooling system to improve the safety of reactor operation is necessary, especially if there is no power at the plant during an accident. Research and development of passive cooling system technology have been carried out in Indonesia since 2011, one of which is by building the FASSIP-02 Test Strand, a large-scale experimental facility. The main components of the FASSIP-02 Test Strand consist of a piping system, expansion tank, water cooling tank, U-shape type heat exchanger, and water heater tank. The occurrence of natural circulation flow rate during operation is determined by the change in the internal energy of each component. Thus, the purpose of this research is to focus on the rate of change of inte rnal energy in a U-shape type heat exchanger based on changes in water temperature in the heating tank. The research method was carried out experimentally by varying the water temperature setting at steady conditions in the heating tank from 70 oC, 80 oC, and 90 oC. After obtaining the temperature and mass flow rate data, the internal energy change is calculated. The calculation results show the relationship between the rate of change of internal energy in the U-shape heat exchanger based on variations in the temperature setting of the heating water at a steady-state, indicating the higher the temperature, the more significant the change in internal energy that occurs, the internal energy changed from 5690 W, 7363 W, and 9768 W. Energy internal increased of 41.75% from the water temperature setting of 70 oC to 90 oC. [ABSTRACT FROM AUTHOR]

The paper presents an analysis and review of sources considering temperature-dynamic characteristics as performance indicators of agricultural automotive and tractor equipment, the impact of energy efficiency of automotive equipment on the temperature and dynamic characteristics of cooling systems, an analysis of the impact of performance indicators of automotive equipment on the efficiency of a block cooling system. An improved scheme of a block-modular cooling system and a method for determining its main indicators during operation for functional units of automotive equipment using innovative materials are proposed. A complex method was used, including an analysis of the state of the issue, theoretical studies of the operating parameters of the polymer radiator of the cooling system with the inclusion of thermal, aerodynamic and hydrodynamic calculations, both in steady and unsteady modes of operation of the MTZ-82 tractor engine. At the same time, analytical and numerical methods, a set of mathematical models and graphic visualization of solutions using the Excel, KOMPAS-3D, Statistica software packages were used. An improved theory of temperature-dynamic characteristics of automotive equipment is used in the cooling system of the MTZ-82 tractor equipped with a polymer radiator, while combined options for using both liquid and oil-liquid engine cooling are possible. [ABSTRACT FROM AUTHOR]

The machining process using the mist cooling method reduces the use of cooling media. Reducing the cooling media and reducing process costs also reduces the waste generated in the machining process. One of the cooling media using the mist cooling method is palm oil. The use of the mist cooling method is not as good as the wet cooling method. Improving the performance of the mist cooling method can be done by adding a solid lubricant. In this titanium machining method, the mist cooling method is used with palm oil media and added solid lubricant Wolfram disulfide (WS2) and TiO2 particles. The solid lubricant used is 0.5; 1 and 1.5 grams/100 ml of palm oil. The spindle speed used is 250, 370, and 600 rpm. Based on the analysis using the Taguchi method, the optimum variation was obtained for 0.75-gram tungsten disulfide, 0.1-gram titanium dioxide, and 394 rev/min spindle speed. [ABSTRACT FROM AUTHOR]

The metalworking process is often used to make a product that is processed from the metal. One of the processes is the machining process using a lathe. The working principle of a lathe is to rotate a cylindrical workpiece on the X axis and use a tool to cut or reduce its profile. The use of a mist cooling system with a mixture of graphite-talc and vegetable oil as a lubricant. This cooling technique is used to extend tool life and improve the surface quality of the resulting workpiece. This study aims to analyze the parameters of the mist cooling system including pressure, angle, and distance which are varied to tool wear and surface roughness of ST 60 steel in the turning process. The research method used is experimental which is then analyzed using the Taguchi method. The mist cooling system parameters uses pressure variations of 0.5 bar, 1 bar, 1.5 bar, angles 0°, 45°, 90°, and distances of 2 cm, 4 cm, and 6 cm. The results showed that pressure and angle had a significant effect on tool wear and surface roughness of ST 60 steel. The results of the analysis of tool wear showed that the optimal variation of 1 bar of pressure, angle 90°, and 6 cm distance resulted in tool wear of 0.0561 mm. The results of the analysis of surface roughness obtained an optimal variation of 0.5 bar pressure, 90° angle, and 9 cm of distance resulting in a surface roughness (Ra) of 0.0036 mm. [ABSTRACT FROM AUTHOR]

The most important application of modern technology that produces both thermal and electrical energy concurrently is a photovoltaic/thermal (PV/T) system. Solar radiation incident on the photovoltaic (PV) panel is light photons and heat, by the absorbed light, generated electrical energy, as long as the temperature of the panel increases due to the heat, which negatively influences the performance. Recently, researchers concentrated on improving (PV/T) system performance, by inventing cooling systems that reduce the effect of heat, the most important of which is utilizing air, water, nanofluids, and combined (water+air) or (nanofluid+air) as a cooling medium. Solar air collector with (PV) module called (PV/T) air collector, a solar water collector with (PV) module called (PV/T) water collector, a solar nanofluid collector with (PV) module called (PV-T) nanofluid collector. And (water+air) or (nanofluid+air) solar collector, with (PV) module called (PV/T) combi collector. Furthermore, studies have shown that the integrated cooling method recorded the highest results of the overall efficiency of about (90%). [ABSTRACT FROM AUTHOR]

Synthetic refrigerants are not environmentally friendly as they can cause damage to the ozone layer, depending on the value of ozone depletion potential (ODP) and global warming potential (GWP). Synthetic refrigerants commonly used are HCFCs that have relatively high ODP and GWP. Therefore, it is necessary to conduct research to find alternative refrigerants that are environmentally friendly. This research uses hydrogen compounds as an alternative refrigerant. To maintain safety in research, flammable hydrogen compounds are not 100% used. Therefore, hydrogen compounds are mixed with refrigerant R134a. This study aims to determine the effect of a mixture of hydrogen with R134a on the performance of the cooling engine by using experimental methods. The parameters obtained from the measuring instrument are used for calculating the cooling rate, COP, and EER. The research results show that adding more hydrogen can affect the COP and EER values due to several factors: the density of the mixture, the pressure of the fluid in the compressor, and electrical energy. The more hydrogen mixture, the smaller the density so that the fluid pressure inside the compressor is lower. The lower the fluid pressure in the compressor, the lighter the compressor performance so that the energy required is getting smaller. This causes COP and EER to be higher in a mixture of 45% hydrogen and 55% R134a refrigerant. It is also necessary to pay attention to the safety level of using hydrogen in the cooling system, adding several safety devices to detect leaks in the cooling system and shutting off fluid movement if the process temperature exceeds the flame temperature of the hydrogen compound. [ABSTRACT FROM AUTHOR]

TRIGA Reactors are a type of Research reactor developed by General Atomics for Training, Research, and Isotope Production. The Kartini Reactor is a TRIGA-type Reactor located in Yogyakarta, licensed to operate at 100 kW. TRIGA reactors are inherently safe due to the prompt negative temperature coefficient associated with the Fuel and Core design. The prompt negative temperature causes a decrease in power level due to the increase in fuel temperature. The phenomena allow the Kartini Reactor to operate without the primary cooling system. During reactor operations at 100 kW, the typical fuel temperature at Ring-B is around 130 °C during normal operations and around 170 °C when operated without the cooling system. This study compares and analyzes literature studies, computational calculations, and experimental results. Literature Review on the topic obtains values ranging from -9.2923×10−5 Δk/°C to -9.7419×10−5 Δk/°C for 135 °C and 180 °C, respectively. Computational calculations using MCNP obtained the value of -7.9620×10−5 Δk/°C for temperatures between 20.45 °C and 226 °C and - 1.1416×10−4Δk/°C for temperatures between 126 °C and 226 °C, which is similar to the value stated in the Safety Analysis Report for the Kartini Reactor of -1.20×10−4 Δk/°C. Experiments conducted on April 25-26th and June 20th, 2022, obtained an average result of 5.4902×10−5 Δk/°C. Hopefully, the results of this study ensure the safety of the Kartini Reactor operations. [ABSTRACT FROM AUTHOR]

Loop heat pipe (LHP) is an alternative technology used as a passive cooling system, which has the potential to be used to absorb and dissipate heat properly. LHP will expect a thermal management solution for the safety of the operation of nuclear installations. Therefore, quality assurance and quality control requirements in IAEA standards are presented on IAEA TECDOC 1910 Quality Assurance and Quality Control in Nuclear Facilities and Activities. One of them is in terms on heat pipe materials and LHP thermal performance, the characteristics of LHP installed with wicks and without wicks (work, design, procurement, inspection, and testing for acceptance). The research method used experimental studies with the performance of the effect of filling ratio, evaporator heat load, and condenser cooling speed on the LHP prototype made. The results show the performance and characteristics of heat transfer: the wicks installed on the LHP function to hold water vapor from rising to the condenser through the adiabatic side without the wick. The water vapor in the evaporator rises to the condenser section through the adiabatic section without a wick. This phenomenon is indicated by the temperature in the adiabatic section without wicks being higher than in the adiabatic sections with wicks installed, with a temperature difference of 12.69°C. The experimental results show that the lowest thermal resistance of LHP is 1.29x10−4 °C/W, which is obtained when the LHP is operated with a heat load of 65 °C, the cooling air velocity in the finned condenser is 2.5 m/s, and the filling ratio is 100%. The phenomena of heat transfer in general heat pipes are overshoot, zigzag and steady. The characteristics of the LHP installed by the wick also have characteristics such as a heat pipe in general where the wick can function as a bridge resulting from condensation. The thermal performance of the LHP is getting better with the increase in air flow velocity, filling ratio, and water temperature used so that it meets the quality assurance quality in terms of work, design, procurement, inspection, and testing for acceptance under these conditions. [ABSTRACT FROM AUTHOR]

The G.A Siwabessy Multipurpose Reactor (RSG-GAS) is one of three research reactors in Indonesia used for radioisotope production, experimental activities, and training. One of the risks of a nuclear reactor, including a research reactor, is the possibility of radioactive release into the environment. PSA Level 1 quantifies the core damage frequency (CDF) for a postulated initiating event (PIE). IAEA has published the safety series SSR-3 that provides examples of selected PIE for research reactors, but each reactor may have other PIE depending on the characteristics of the design. PIEs for RSG-GAS are defined solely based on the manufacturer's data and have never been systematically evaluated. Hence, it is necessary to systematically evaluate those pre-defined PIEs. This study aims to evaluate the PIEs of the RSG-GAS secondary cooling system using the HAZOP method. It is important because the possibility of the reactor temperature could increase if the secondary cooling system fails to remove heat from the core, and, hence, can cause radioactive substances released into the environment if the secondary cooling system leakage and the protective measures are failed. This study evaluated 7 possible events and the results show that all events have low risk, low consequence, and/or rare frequency. Therefore, those 7 events did not meet the PIE criteria. Nevertheless, we still recommend that RSG-GAS pay attention to those identified events and provide additional procedures to periodically check the radioactivity concentration in the secondary water when PA-01/PA-02 CR 001 is activated. [ABSTRACT FROM AUTHOR]

An electron accelerator receives heat mainly from radiofrequency resonance. This correlates to the increase in temperature for the inner components of the accelerating structure. An analysis of the thermal characteristics within an accelerating structure of a high-energy electron accelerator has been performed by utilizing Monte Carlo radiation transport code in dose deposition calculation. Two accelerating structures, one with 5 modules and one with 7 modules, have been considered for analysis. A multi-source approach has been done to accommodate the increase in energy for each acceleration module and to equate the sources power to the analytical power loss from resonance. Each source has a conical spread to cover as much area with the sources power in each cavity. The dose in each inner component of the accelerating structure is then applied to a calorimetric heat transfer calculation to determine the temperature difference. Through this analysis, it has been found that the average temperature increases of up to 10.2401 K and 12.3555 K in 5-module and 7-module structures respectively for each radiation hour can occur without a proper cooling system in place. A peak temperature increase at a single point along the accelerating structure has been calculated to reach 75.1975 K and 107.2558 K. Furthermore, the effect of photon creation from electron-matter interaction becomes more prominent in the latter modules of the accelerating structure and accounts for up to 0.5688 K and 0.9753 K average temperature increase. [ABSTRACT FROM AUTHOR]

The use of a water spray system as the glass cover cooling of single slope solar still was experimentally investigated as an attempt to enhance the daily productivity of solar still. The cooling water was sprayed in a pulse form for 30 sec while the time between any two successive pulses was altered as 5 minutes, 10 minutes, 20 minutes, and 30 minutes, respectively. the present work also considered the form of continuous cooling water spray. The collected result highlighted that the daily productivity of conventional single slope solar still enhanced by 10%, 14%, 27%, 17.5%, as single slope solar integrated with a cooling system of (30 sec/ 30 min), (30 sec/ 20 min), (30 sec/ 10 min), and (30 sec/ 5 min), respectively. Where the best pulse timing was (30 sec/ 10 min) since any farther increment induces a negative influence on the daily output of the conventional single slope solar still. [ABSTRACT FROM AUTHOR]

Passive cooling systems in buildings are inseparable from thermal comfort, particularly in regions with tropical climates. Natural Ventilation (NV) as one of the passive cooling systems can be the solution to issues of thermal comfort and energy conservation as it is proven to achieve thermal comfort in a building. Low ventilation is one of the Natural Ventilation systems that is proven to increase indoor air velocity and thermal comfort in a building. This study examines how the height of low ventilation affects indoor air velocity and thermal comfort in a building model with dimensions 2.5 m x 2.5 m. The research employed 180 data of indoor and outdoor air velocity (m/s) with an interval of 1 minute for each height of vents. The heights of the low ventilation in the research are 10 cm, 40 cm, and 70 cm from the floor surface of the model building. From 540 data, it is concluded that with relatively the same wind speed, the low ventilation with a height of 10 cm has the highest air velocity. The lowest air velocity is obtained from the low ventilation with the highest height, which is 70 cm. The research significance is to give a new consideration of the location of the vent holes, particularly low ventilation holes. With their effectiveness in increasing the air velocity, thermal comfort in the building can also be achieved without the use of an active cooling system. [ABSTRACT FROM AUTHOR]

The rapid development of motorbikes lately is marked by the many variants (types). Motorcycles are the most widely used means of transportation by Indonesian people in general. The completeness system of the machine includes the ignition system, filling system, lubrication system, cooling system, starter system and fuel system. Good engine performance is supported by several factors including fuel consumption in accordance with the working conditions of the engine, proper ignition timing, high engine compression and a strong spark to burn the entire mixture of gasoline and air at the end of the compression stroke to produce the desired combustion. to find out how the AC CDI ignition system works for the Honda Astrea Grand motorcycle and the 110 cc CDI DC Shogun ignition on CAMEL IBATE vehicles. To get a more efficient/efficient fuel flow discharge. The data analysis method to determine the fuel flow rate is by testing the Camel Ibate vehicle using the Honda Grand Standard AC CDI and the 110 cc Shogun CDI-DC at 3500 Rpm, 4000 Rpm, 4500 Rpm, 5000 Rpm, 5500 Rpm, to get the time difference required in testing the fuel flow discharge with. At 3500 rpm engine speed, the time difference between AC CDI and DC CDI is 16.22 seconds. At 4000 rpm engine speed, the time difference between AC CDI and DC CDI is 17.9 seconds. At 4500 rpm engine speed, the resulting time difference between CDI AC and CDI DC is 15.64 seconds. At 5000 rpm engine speed, the time difference between AC CDI and DC CDI is 20.97 seconds. At 5500 rpm engine speed, the time difference between AC CDI and DC CDI is 13.09 seconds. [ABSTRACT FROM AUTHOR]

The disadvantages of the contactless automatic voltage regulation (CAVR) system with the reactor switching device (RSD) operated on the of 3.0 kV DC traction power supply system are analysed. The direction of its improvement is determined. The functional scheme of closed-loop CAVR system of a converter unit with thyristor-reactor switching device (TRSD) and converter transformer TRSNP-12500/10 (three-phase special converter transformer with natural air cooling system with the power 12 500 kVA) has been considered. The technical and economical comparison of two modes of traction power supply system (TPSS) operation has been performed: without introducing voltage regulation devices at traction substations with the no-load voltage of 3500 V and with introducing voltage regulation devices by CAVR system at the voltage regulation levels of 3500 V, 3600 V and 3700 V with different variants of switching devices. The economic efficiency of using the CAVR system with TRSD has been determined. [ABSTRACT FROM AUTHOR]

Technological development refers to improving performance and checking dimensions, especially in car cooling systems. The impact of these developments causes an increase in the heat flux produced so that conventional cooling fluids cannot handle it and are starting to be abandoned. One of the most popular cooling systems in cars is the radiator. The use of nanoparticles has also begun to be widely used as an alternative working fluid, both as a working fluid for radiator cooling systems and as a working fluid and other cooling technologies. This test was performed on a simulated radiator cooling system on a standard car and varied the mass flow rate at 4 lpm; 3 lpm; 2 lpm and volume fraction 0. 1% on the composition of nanofluid Al2O3−Water and water-base fluid and the process of testing the heat transfer rate is carried out by heating the working fluid in the heating tank to 80°C then running it on the car radiator cooling system for 10 minutes and the visual results of the temperature drop will be read in the Labview program. The test results show that the higher the mass flow rate, the greater the heat transfer rate of the working fluid, In this test, the Al2O3−Water nanofluid showed a better heat transfer rate than. [ABSTRACT FROM AUTHOR]

The insulation material provides reduces the heat loss or gain into the structures. Several insulation materials are used to attain the desired comfort conditions. In this proposed work, insulation materials namely rock wool, Fiber Glass and Polyurethane foam (PUF) are used in sequence. The solar thermal system receives heat energy which is used to produce cold or hot water through Phase Change Materials (PCM) by utilizing its latent heat. The temperature distribution through various layers and materials are predicted by means of ANSYS Fluent simulation. Also, the temperature variation due to seasonal changes for various insulation materials are computed. It is concluded that PUF insulation provides better performance compared to other materials. [ABSTRACT FROM AUTHOR]

Today's thermal power plant cooling systems aim at reaching high steam cycle efficiencies in all operating points while keeping the water consumption as low as possible. For this purpose, cooling systems are becoming more and more complex, such that finding an optimal operation strategy for the cooling components is no longer a trivial problem. To tackle this problem, this paper introduces a cooling operation optimization algorithm. The algorithm is applicable to a black box model of the power plant including the cooling system. Thereby it can easily be applied as online optimizer for existing cooling systems or to investigate different cooling options for different CSP plant configurations during a planning phase. Additionally, the weight of water consumption and electricity production can be adjusted for each optimization run. In this work, we present the algorithm itself by providing a methodology to transform the optimization problem into an oriented decision tree and to solve the resulting problem with a stochastic solution approach developed from an Ant Colony Optimization algorithm. Furthermore, the operability of the algorithm is validated using a performance model of a 50 MW parabolic trough plant with a hybrid cooling system, consisting of a wet cooling tower and a cold thermal energy storage. [ABSTRACT FROM AUTHOR]

As the demand for human comfort grows, technology that is competent, operative, and viable must be established. For cooling, purpose heat exchangers design is evolving and the application of this type of exchangers is growing swiftly in industries like food, air conditioning, power production, refrigeration, biomedical field, and automobile cooling system. Now, these days it is essential to come out with a device that is energy-saving at a lower cost. So, it is necessary to develop a heat exchanger that has the quality of high heat transfer, lower transfer time, and higher effectiveness. This can be done if we improve the thermophysical property of refrigerants. In the existing work, a computational examination is done on the viability of using nanofluids-water coolants in an automobile cooling system. Computational geometry is developed in ANSYS FLUENT. [ABSTRACT FROM AUTHOR]

Several previous researches suggested designs for wearable devices to measure, check, and monitor a patient's temperature and measure brain temperature. Scientific studies have shown that using hypothermic devices reduces mortality rates and reduces in the long run. In case of injury, the human brain is weak and affected by fluctuating temperatures, and it is challenging to control brain temperature manually. The Human Brain Hypothermia (HBH) methods were classified in this paper. The techniques and types of cooling systems to reduce brain temperature, including brain cooling, blood cooling, and skin surface cooling, have been reviewed. In addition, the main objective of the reviewed research is to discover the systems and devices that lower the temperature of the human brain and body. Moreover, a comparison of previous works for HBH was achieved in terms of adopted method, sensor type and location, and temperature Hypothermia value. The disadvantages or limitations of the previous studies were critically reviewed. [ABSTRACT FROM AUTHOR]

This study investigates the performance of a mobile cold storage system designed for the transportation of vaccines at a very low temperature, in order to prevent spoilage. The system has a cylindrical storage unit for vaccines surrounded by a layer of phase change material (PCM) and an insulation layer on the outside. Two different designs with the same volume but different in thickness of PCM and insulation have been examined in this work. Suitable insulation and PCM materials are picked for the design of the system and further investigation. Polyurethane and 0100-Q-50–Bio-PCM are taken as the insulation and PCM materials, based on several factors like ease of availability, cost factor and bio compatibility issues. The inner air chamber is to be maintained at a temperature of 213K-230K to prevent spoilage of the vaccines. Model 1 has 2 cm thickness each of PCM and insulation, while model 2 has a thickness of 3 cm PCM and 1 cm insulation. The cooling time for model 2 was more than model 1 by 1.7 hours, and the cooling efficiency was also more than model 1 by 3 %. This preliminary study has helped to provide an insight into the further development of an optimal mobile cold storage system, which can be used efficiently and economically for the transportation of vaccines. [ABSTRACT FROM AUTHOR]

The Ranque–Hilsch vortex tube is a device which divides a flow of compressed air or gas into two different streams of fluid, a hot and a cold stream of air or gas. After the innovation of the vortex tube in 1933, there has been a massive amount of literature on the topic. Many researchers around the world are interested to enhance the performance of vortex tube. Since the device is very simple, lightweight, and noiseless, it does not use any traditional refrigerants like Freon, also it does not have any mechanical moving parts, the vortex tube is well-suited a variety of industrial settings, including cooling applications like lubricants in CNC machines, drier, refrigerators, medical cooling and biological applications, desalination, automated spot cooler and heating processes, traditional machining processes among others. This article represents a review on Ranque-Hilsch vortex tube and focuses light on three aspects. In the first section it describes the introduction concepts and the constructional details. The second section describes about the mechanisms that dominates the phenomena of energy separation within the tube and discusses about some popular theories. The third section discusses about the recent advancements in the direction of numerical analysis of vortex tube along with the design parameters, the numerical tools along with the models and their key findings. The discussion and the conclusion will help the designers to further increase the performance of the device which will capable it to be adoptable in any cooling and refrigeration applications. [ABSTRACT FROM AUTHOR]