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Exploration wells which are considered unproductive due to the low temperature and the liquid phase cannot be used directly, either flash steam or dry steam. For this reason, it is necessary to make a breakthrough to continue to produce electricity with a binary cycle system, so that cost losses in the exploitation phase can be reduced. For this reason, it is necessary to design a practical small-scale binary cycle unit, by designing the type and dimensions of the heat exchanger, piping network, gas turbine, condenser and foot pump. The selection of the DM-01 well which is an exploration well as a supply of heating fluid is because it has a pressure of 10.5 bar and a temperature of 120°C. at a rate of 5 kg/s. The heating fluid is flowed through a 4.5inch diameter pipe from the wellhead to the heat exchanger at a distance of 100 m to heat the working fluid. The cycle that occurs is that the working fluid from the feed pump goes to the heat exchanger and then flows to the turbine then the condenser and returns to the feed pump. By using a heat exangger plate with a heat transfer area of 350 ft2 so that it can increase the temperature of propane to 266 °F so that all propane becomes gas and drives the gas turbine into electric power. [ABSTRACT FROM AUTHOR]

Experimental power reactor (RDE) is a 10 MWe high temperature gas cooled reactor that is designed by BATAN. A preliminary heat transfer analysis of hot gas duct, an important part in the reactor, has been studied and the result was satisfying and could be reanalyzed to obtain the exact method to solve the heat transfer issue. The design is simplified to maintain the specific parameter that will be analyze. The parameter are temperature, pressure and mass flow. The result is compared to technical RDE data and the result show that the error is below than 5%. This result is enough to represent the actual data and can be used to be the further design. The insulation material also put some effect that maintain the hot gas temperature stable. [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]

This study investigates numerically the thermal-hydraulic performance of 0.02-1% water-based Al2O3 nanofluid in circular and square ducts with and without twisted tape insert. Two twist ratios of 5 and 0.579 are examined. The Reynolds number considered is from 20000 to 100000. The two-phase approach is employed to simulate the flow of nanofluid. The thermal performance of nanofluid in the circular pipe with insert is better than the case of the square duct with insert, but the friction factor of the circular tube is also relatively larger. Furthermore, a lower twist ratio yields a higher heat transfer rate. The results also reveal that the incorporation of nanoparticles and twisted tape insert contributes to heat transfer augmentation but at the expense of a higher friction factor. Nevertheless, from the thermal-hydraulic perspective, their application in circular and square tubes is considered practicable as the values of performance evaluation criteria obtained are more than one. The maximum thermal performance factor of 2.546 is achieved by 1% Al2O3 nanofluid in the circular duct with insert (twist ratio: 0.579) at the Reynolds number of 20000. Therefore, the use of the circular tube with insert is more favourable compared to that of the square tube. [ABSTRACT FROM AUTHOR]

The analysis of the impact of different air inlet conditions (0°, 45° and 90°) and baffle layout forms the basis of this experimental investigation. In single-phase internal flow, baffles in the channel are typically employed for passive heat transfer augmentation approaches. In order to investigate how temperature affects heat transfer, the air supply is given at four distinct temperatures—30°, 35°, 40°, and 45° degrees Celsius—and the input temperature are adjusted accordingly. Reducing heat exchanger sizes and costs is usually the primary goal of this analysis. Nonetheless, research has been done on how baffles and other input conditions affect pressure drop and heat transfer. A baffle is a common element used in many heat-exchanging routes to increase heat transfer. According to the restricted fluid flow space caused by flow obstructions like baffles, there is an increase in pressure drop and an increase in viscous impact. Nonetheless, research has been done on how pressure drop and heat transmission are affected by baffle height and various input circumstances. Lastly, a difference between the experimental investigation's findings and those derived from the correlation method will be made. Because of their reduced fluid flow area, flow obstructions like ribs raise the viscous effect and pressure drop. There are three types of flow around the ribs: secondary, reattachment, and recirculation. While secondary flow produces a swirl, it also improves the thermal contact between the fluid and surface. This leads to the fluidmixing that improves the heat gradient and, in turn, the heat transfer coefficient. [ABSTRACT FROM AUTHOR]

Heat transfer is one of the processes used in industry and one of the tools needed to carry out heat transfer is a stirred tank equipped with a coil and jacket. The heat transfer experiment was carried out in a stirred tank with tap water as the feed used. The tap water as a hot fluid and a cold fluid. Heat transfer will not occur if there is no driving force, where in this experiment the driving force is the temperature difference between the hot fluid and the cold fluid. The heat transferred is expressed as the heat transfer coefficient. The overall heat transfer coefficient represents the overall heat transfer event in the heat transfer area, where the magnitude of the coefficient will be proportional to the driving force. The value of the overall heat transfer coefficient (Uo) can depend on the temperature of the hot fluid, the stirring speed, and the flow rate of the cold fluid. So that the research variables used are hot fluid temperatures of 350C, 410C, 470C, and 530C, stirring speeds (N) of 1 and 3, and cold fluid flow rates of 0.1 LPM, 0.15 LPM and 0.2 LPM. The heat transfer experiment in a stirred tank with this coil can be concluded that the value of the overall heat transfer coefficient (Uo) will be greater if the cold fluid flow rate (Qc) and stirring speed (N) are greater. Then the greater the temperature of the hot fluid (Th), the greater the value of the overall heat transfer coefficient, the individual inner heat transfer coefficient, and the outer heat transfer coefficient. [ABSTRACT FROM AUTHOR]

An experimental investigation of thermo-hydraulic performance for a square cross-section air channel with dimensions of (15cm×15cm) and a length of (1.3 m) is considered in the present work. The experimental rig is fabricated from steel (ASM4120) with rectangular periodic eight ribs with dimensions of (3.75 cm ×7.5cm) along the lower wall of the air channel and its exhibition to constant heat flux (1500 and 3000) W/m2. The range of the Reynold numbers is varied by (6000,8000,1000 and 12000). All results are compared with the smooth channel model, the results showed that the best heat transfers are noted in the case of (Re = 8000 and q" = 3000 W/m2) where the Nusselt is enhanced by 7 % when using the ribbed lower surface of the air channel. Also, the maximum value of the friction factor occurs in the case of a ribbed duct at the condition of (Re = 6000 and 3000 W/m2) where the friction factor is increased by 19 %. Finally, the thermo-hydraulic performance factor was about 1.11 and which indicates the enhancement that occurred by adding the ribs for the smooth channel. [ABSTRACT FROM AUTHOR]

Thermal heat pipes are widely used to enhance heat transfer in heat exchangers. They enhance heat transfer by using a two-phase flow of the working fluid, as the vapor phase of heat can be absorbed in the evaporator section and rejected during the liquid phase in the condenser section. In this study, a numerical analysis of the performance of a thermosiphon heat exchangers with different diameters, different mass flow rate ratios and different tube arrangements to reach the highest forced convection heat transfer coefficient was performed. The results obtained were validated using the validated associations available in the literature and compared with previous studies. The results of the study showed that the gradient arrangement has a higher heat transfer coefficient than the direct arrangement at the same mass flow and tube diameter. The numerical results can be used to design a thermosiphon tube and use in experimental studies. [ABSTRACT FROM AUTHOR]

The present study is concentrate on the effect of using baffles in a rectangle duct to enhance the heat transfer over heated blocks. For this purpose, an experimental and numerical study implement. In the experimental study, a test rig is consisting of a rectangular duct and square baffle which are attached at the top wall at mid positions between two heated blocks with a constant heat flux apply at the bottom wall is built up and using. In the numerical study, mesh generation and finite volume analysis are perform by using ANSYS-Fluent 22(R2) with (k-ε Realizable) turbulent model to calculate the pressure drop, temperatures, and heat transfer rate. The study is concentrate on the effect of baffle position, and number for the range of Reynolds number (12000-28000) and using air with (Pr=0.72) as a working fluid. The results show that inserting a square baffle at the center heated block of the duct leads to increasing the Nusselt number by (62%) comparing to that duct with no baffles and (54%) with that at high (11.25 cm) and center position for the heated block. Comparing numerical and experimental shows a good agreement between them with a maximum deviation (8%), also a close agreement notice when comparing the present results with some of the previous works. [ABSTRACT FROM AUTHOR]

Now a day, a numerical simulation for a double pipe heat exchanger (DPHE) with a counter-flow is presented in order to study the effects of adding longitudinal (triangular and rectangular) fins attached to the inner tube exterior surface with dimensions (2×6 ×1000) mm and the number of fins (8) fixed for all types of fins. With different amounts of mass flow rates for the hot and cold sides, the benefits of the fin type were studied further studying the effect of three heights (4, 6 and 8) mm for the type of fins that give better thermal performance. The results showed that the heat transfer improvement was about 15 % and 11% when using rectangular and triangular fins respectively as compared with the smooth tubes. The triangular fins show a lower pressure drop of 49.6% compared to the regular tube, while the rectangular fins give a pressure drop of 59.8% compared to the regular tube. [ABSTRACT FROM AUTHOR]

A thermal simulation of a double pass solar air heater with different configurations of Zig-Zag absorber plate by using COMSOL software is presented numerically and the turbulent model is solved using (K ̶ Ɛ) model with the range of Reynold number of (5000-16000). In this study on the air solar heater with dimensions of (755 mm × 182 mm × 1000 mm) with absorber length of (655 mm) for various dimensions of Zig-Zag absorber plate were simulated numerically. The examinations have been performed on worth of solar irradiance 900 W/m2 and at various mass flow rate of (0.015, 0.02 and 0.025 kg/sec). Hypothetically, the outcomes showed that the ding Zig-Zag absorber plate absorber will be increasing the Nusselt number is with upgrade percent of (66 %) as compared with smooth flat plate absorber. [ABSTRACT FROM AUTHOR]

Nowadays, the increase of the consumed energy within cooling applications is still high. Therefore, enhancements and advancements of the thermal performance for those cooling applications with high heat transfer capabilities have a great importance. Thermosiphon and its integrated systems are one of best methods to assist thermal applications to transfer the heat energy with less power consumption. Thermosiphon mechanism involves evaporation of the working fluid by heat source and rejecting the transferring heat by condensation to the heat sink efficiently as compared to fins, or any auxiliary surfaces. Therefore, the seeking about more appropriate methods to enhance the heat transfer rate by thermosiphon are still required. The effects of thermosiphon inclination angles, the working fluid types, filling ratios, operation limitations and thermosiphon geometries are aimed to be focused throughout this reviewed study. The present study includes a wide range of literature survey that have been reported with emphasis on different investigated parameters for the thermosiphon applications. Obviously, it is tended to overcome most possible operation conditions, design limitations, and governing models in numerical and experimental works. The outcome results proposed that the best thermal performance for the thermosiphon have been executed under vertical position, middle range of the filling ratio and high active pressure. Also, the use of organic working fluid assists the thermal performance of thermosiphon. Furthermore, the lowest thermal resistance is reached under filling ratio range of 30%-60%; and the geyser boiling effect can be eliminated by increasing the applied heat with the filling ratio. Numerically, the use of (Volume of Fluid) VOF, UDF (User Defined Function) and Lee models provide more accurate results in the CFD (computational Fluid Dynamics) approach. According to this wide review, different investigations and recommendations were showed to present a clear knowledge about the thermosiphon and its applications, and to be as a basis for the future works. [ABSTRACT FROM AUTHOR]

An experimental and numerical investigation of the forced convective heat transfer of arrays of twice two-dimensional blocks with slots at the backside of every block is reported. The objective of the present study is to investigate the effects of the slot size 0.004≤ Sj≤ 0.006 m with relative slot jet velocity Vj = 1, 2, 4 m/s, slot distance Xj = 0.010. 0.030, 0.050 m, on the flow features and induced heat transfer enhancement, and to study the effect of slot jet on the region behind the heated blocks, with the main duct Reynold number (12000 ≤ Re ≤ 25000) on the local Nusselt numbers and mean Nusselt number for the block's surfaces. Surface heat fluxes on the block were constant. q" = 2000 W/m2. Comparisons of the Local Nusselt number with peripheral distance for different Reynold numbers and different slot sizes and mean Nusselt number. all experimental cases were simulated with ANSYS Fluent 2020 R1. It was found that the temperature of the block decreased with an increase in the Reynold number and with an increase in the slot size and there is a good agreement found with the experimental result. [ABSTRACT FROM AUTHOR]

The current research aims to improve the performance of the counter-flow heat exchanger for a double tube heat exchanger numerically and experimentally in the Reynolds number range between 2000 and 4000. To maximize heat transfer of the heat exchanger under study, a passive method of enhancement of heat transfer was used by using helical fins perforated on the annular side with different diameters of 3, 5, and 7 mm. These fins act as vortex flow devices, creating turbulent conditions for the boundary layers of the fluid, thus increasing the heat transfer coefficient. The numerical results of the current study have been obtained by using the ANSYS Fluent 2022 program. The results show a good agreement between the numerical and experimental findings of the traditional model of the current study and the results of previous studies. Furthermore, the findings showed that the comparison between the numerical and experimental results of the optimum model is identical. Moreover, it was found that the best model among the new models is when a 20 mm pitch is combined with a 10 mm spiral height and a 5 mm hole diameter. In addition, the friction factor of the best model decreases by 20.046%, the overall heat transfer coefficient increases by 67.915%, and the Nusselt number increases by 63.954% compared to the conventional model. The highest value in thermal performance for the best model is 1.855% compared to the conventional model. [ABSTRACT FROM AUTHOR]

Many manufacturing processes use the impinging jet method. This article summarizes the thermal transfer properties of alternating twin-impinging jets. Heat transfer and other features of jet impingement on surfaces have been the subject of many experimental investigations. The most crucial problems were the possibility of improving flow and heat transfer and the relevant elements related to these behaviors. There is a severe data deficiency about the heat transfer problem caused by jet impingement. Up to now, there has been no research on the mechanism of pulse twin jet with the nano-coating application. Since then, little written evidence has demonstrated how computational and experimental methods might improve heat transfer using pulse twin jet processes. Due to the absence of previous data, new research and debate on the topic are required. To better understand the elements that affect the flow and heat transfer performance of exciting multiple impinging jets, this work analyzes both computational and experimental experiments. In addition, the pulsating impingement jet improved the Nusselt number, according to the literature. The authors investigated the effect of surface Nanocoating, Reynolds number, nozzle spacing, and distance between nozzle and plate in this technique, which leads to a reduction in consumed energy, cost, and process time. Nano surface coating was useful in increasing heat transfer rate, and a high Reynolds number has a greater effect on the Nusselt number. Similarly, this study aims to identify the gaps in knowledge around using multiple stimulated jets to improve flow and heat transfer and the critical factors connected with this issue. In order to test the following hypotheses, a comparison of studies on pulsing impingement jets was conducted. TiO2 nanoparticle surface coating could expedite heat transfer. With the proper adjustment, the impingement jet technique could enhance heat transfer. [ABSTRACT FROM AUTHOR]

In this research article investigation was done on the stability of ZnO, TiO2, F-MWCNT based mono and hybrid nanofluid using a mixture of distilled water & ethylene glycol (E.G.) as a base fluid. Most of the research works highlighted the properties of nanofluid. Hence stability of nanofluid is studied in this research work. Mono and hybrid nanofluid were formed by the use of a two-step method with various vol. fraction without use of surfactant. Sedimentation photograph capturing method and Zeta potential test used for stability analysis. 0.1% vol. concentration of nanoparticles shows good dispersion in the base fluid. Sedimentation of nanoparticles observed with increase in vol. concentration of nanoparticles and time. The Zeta potential values were observed in the range of 20 - 34.4 mV for a 0.1% vol. fraction of mono nanofluid and 29.3mV for hybrid nanofluid, which indicates that nanofluid has moderate stability. So low vol. concentration nanoparticles in hybrid nanofluid will be a promising coolant for heat transfer application, as a small amount of addition of nanoparticles of F-MWCNT along with ZnO and TiO2 will help to increase the thermal conductivity of hybrid nanofluid. [ABSTRACT FROM AUTHOR]

This study focuses on the investigation of unsteady stagnation-point flow and heat transfer over an exponential stretching/shrinking sheet immersed in a hybrid nanofluid. Hybrid nanofluid is an engineered fluid and can enhance thermal conductivity and heat transfer efficiency and stagnation-point flow is important in designing heat exchangers. Hence, the heat exchange process such as in power generation, and refrigeration becomes more effective. This mathematical model applied the Tiwari and Das model where Al2O3 − Cu hybrid nanofluid is considered. The base fluid is water, and the shape of the nanoparticle is considered in sphere shape. The ordinary differential equations are solved using the bvp4c function in the Matlab program to obtain the skin friction coefficient, heat transfer rate as well as velocity and temperature profiles. This study provides some tables of the skin-fiction coefficients and heat transfer rate values for the validation with the previous study and new values for the future study. This study reveals that dual solutions exist for suction s > sc. The increase of copper nanoparticles expands the solution and increases the skin friction coefficient at the surface. Meanwhile, by considering the higher effect of the slip parameter, the findings show an increment in both skin friction coefficient and heat transfer rate at the surface. The heat transfer rate is seen increasing by considering the same value of nanoparticle Volume fraction for copper and alumina compared to the different values. [ABSTRACT FROM AUTHOR]

This article reports the dynamics and heat transfer of power-law hybrid nanofluid flows along a cylindrical coordinate plane. The Tiwari-Das heterogenous model for the non-Newtonian ethylene-glycol (EG) mixtures due to the nonlinear radially power-law stretching curved surface are saturated with hybrid graphene-CuO, graphene-MgO and graphene-GO nanoparticles. To the best of our knowledge, investigation on such flows with combination of the EG base fluid, hybrid graphene and variant oxides nanoparticles were never attempted by any researcher despite the basic heat transfer model. The partial differential equations of continuity, momentum and energy highlighting the incompressible steady hybrid nanofluid flows are reduced to coupled ordinary differential equations using similarity transformations. The resulting equations are then converted to a boundary value problem (BVP) and solved using a bvp5c algorithm in MATLAB environment. The numerical results for the flows are generated while the velocity and temperature profiles are sketched for analysis. It is concluded that all the considered hybrid nanofluids demonstrate enhancement in the heat transfer and skin friction magnitudes as compared to the mono nanofluids and the base fluid alone. Moreover, additional nanoparticle Volume fraction consistently heats up and slows down the nanofluids except for the graphene-GO/EG mixture. The patches within the GO nanostructures may permit capillary driven mechanism, typically found in ultrafast flows, that allows the velocity enhancement of the nanofluid despite facing the steadily increasing friction at the nonlinear power-law radially stretching surface. [ABSTRACT FROM AUTHOR]

Due to the hardship, high expenses and inaccuracy of practical experiments in predicting the performance of an evaporative air conditioner, the convection heat and mass transfer within the air-water film in a direct evaporative cooler are analyzed theoretically. The mathematical development of an equation to evaluate the cooling effectiveness is presented to predict the performance of a direct evaporative cooler. The unsteady performance of heat and mass transfer based on the use of a water-wetted surface and the use of air is compared and discussed. In addition, the effectiveness of saturation and outlet dry bulb temperature of the air is determined. The predicted cooling effectiveness and outlet dry bulb temperature of the air was realistic and matched the expectations of the behavior of a direct evaporative cooler that works in the city of Karbala. The predicted results present the worldwide validity of this method to evaluate the performance of direct evaporative coolers to avoid the costs of experimental tests. [ABSTRACT FROM AUTHOR]

A number of models and modelling approaches for phase transitions of phase change materials (PCMs) have been proposed in recent years. However, many of these models have not been thoroughly validated with experimental data. This is in particular the case of the models for thermal hysteresis and partial phase transitions of PCMs, where the design and execution of relevant experiments is difficult. The most widely used experimental techniques for characterization of PCMs - Differential Scanning Calorimetry (DSC) and T-history method – require minimization of the temperature gradients in the test samples and thus the obtained results do not represent very well the behavior of PCMs in thermal energy storage (TES) systems (where large temperature gradients in PCMs are commonplace). An experimental set-up for the acquisition of data suitable for validation of phase change models have been proposed and assembled. The set-up can be used for the model validation in case of both the direct and inverse heat transfer problems. The set-up is based on the monitoring of the phase change front propagation in a rectangular cavity, where the positive or negative heat flux is introduced at one of the cavity walls. Such an arrangement results in (often significant) temperature gradients in a PCM. Unlike in similar experimental set-ups, where a heat transfer fluid (HTF) is used to introduce the heat flux at the wall, the Peltier cells are used in the proposed experimental set-up for this purpose. Also, most experiments reported in the literature only addressed the melting process (heating of a PCM) with the positive heat flux introduced at the wall. The Peltier cells allow for relatively quick switching between the positive and negative heat flux (heating/cooling) and as a result the thermal processes similar to real-life operation of TES systems can be investigated. The cubical cavity with 250 mm long internal edges is made of PMMA. The wall, at which the heat flux is introduced, is made of a 15 mm thick aluminum plate with embedded RTD temperature sensors for wall temperature monitoring. A heat flux sensor is installed on the side of the aluminum plate facing the PCM (the heat flux sensor covers the entire surface of the plate). An extended heat transfer surface in the form of a finned aluminum sink is installed on the Peltier cells to improve the heat transfer between the cells and the ambient environment. [ABSTRACT FROM AUTHOR]

This work discusses the results of the temperature measurements performed on a water-based slurry, seeded with polystyrene spherical particles and flowing in a heated horizontal pipe. The flow is fully turbulent, characterized by a Reynolds number between 4500 and 14000. Two particle size distributions are tested (with mean diameter of 0.35 mm and 0.85 mm respectively), which lead to homogeneous and heterogeneous flow regimes. A solid volume fraction up to 7% is reached. The results show that particles increase the liquid bulk temperature by lessening the mixture heat capacity. Moreover, the particles increase the liquid heat transfer co-efficient. Additionally, in the bottom part of the pipe, the heat transfer coefficient behaves similarly to fluidised bed. Based on these results, a new semi-empirical correlation for the slurry Nusselt number in function of the relevant dimensionless groups of the problem (Reynolds and Prandtl numbers, density ratio, particles size to pipe diameter ratio and solid volume fraction) is proposed. [ABSTRACT FROM AUTHOR]

This work describes metrology investigations that include uncertainty estimation of contact temperature measurements performed using K- and T-type thermoelements. Temperature measurements were essential in experiments on heat transfer during fluid flow in minichannels. The data acquisition station was used as the main system for collecting temperature data. For metrology investigations of temperature measurement by selected thermoelements, a dry well calibrator was applied. The temperatures measured by the thermoelements were statistically compared using the reference temperature preset on the calibrator. Corrections to the temperature measurement performed by the tested thermoelements were calculated. The relative experimental error and the method accuracy for the thermoelement measurement were determined. The uncertainty of the difference in the temperature measurement for the thermoelements tested with respect to the reference temperature was also provided. The results differed depending on whether the temperature increased or decreased. It confirmed the hysteresis phenomenon. [ABSTRACT FROM AUTHOR]

The main objective of this study is to estimate the uncertainty of surface temperature measurement using the Monte Carlo method. The calculation is based on an experimental study on heat transfer during fluid flow in a group of parallel minichannels with a common heated wall. Temperature distributions on the heated wall surface were performed simultaneously using infrared thermography and K-type thermoelements. Infrared thermography is the contactless temperature measurement method, while thermoelement measurement is the contact method (measurement at selected points). Example results of both methods of temperature measurement were presented and discussed. In the calculations, the Monte Carlo method was used to estimate the uncertainty of surface temperature measurement uncertainty. Comparative analyses of Monte Carlo simulation results and uncertainty spreading methods were carried out. The results obtained from these two methods were found to be consistent. [ABSTRACT FROM AUTHOR]

Heat transfer inside a cylinder and the cylinder head of a reciprocating compressor is responsible for the majority of thermodynamic losses in these devices. Both the magnitude and direction of the heat flux through the walls of those components change several times during a single revolution. They are directly dependent on the position of the piston and suction/discharge valves. A better understanding of these thermal processes could lead to better and more targeted cooling. This would result in higher efficiency of the reciprocating compressors. In this paper, two experimental methods for determining heat flux are used. The first method uses heat flux sensors to measure heat flux directly. The other one is focused on the indirect assessment of heat flux via surface-mounted thermocouples. To tie the measurement to the position of the crankshaft, both sensors are coupled to a rotary encoder. The rotary encoder sends a signal once per revolution when the piston is in the top dead center position to trigger signal acquisition. The results show signs of reaching a quasi-steady state and would most likely require sampling of the signal more times per revolution. [ABSTRACT FROM AUTHOR]

The present analysis is aimed to study the influence of gravity modulation on Jeffery fluids saturated anisotropic porous medium. The solution of Ginzburg-Landau equation (GLE) is derived to calculate heat transfer with the help of weakly nonlinear analysis. The graph shows that the start of convection is increases by increase of mechanical anisotropic parameter and Jeffery parameter, on other hand the start of convection is delayed for thermal anisotropic parameter. The Nusselt number is decreases with increase in Jeffery parameter, mechanical anisotropic parameter and thermal anisotropic parameter so heat transfer diminish and therefore system become stable. On other hand heat transport increases due to increase in Vadasz number so system become unstable. [ABSTRACT FROM AUTHOR]

In this paper, the temperature distribution of porous fins is approached by the Akbari-Ganji method using a simple analytical technique. The Darcy model and energy balance were also utilised to create the heat transfer equation. An insulated tip and a limited-length fin serve as a case for exploring thermal performance. The outcomes of the Akbari-Ganji method are compared with previous results. The boundary value is also solved numerically using the MATLAB programme for validation. The outcome indicates that the Akbari-Ganji is more reliable, appropriate, and accurate than other approaches like the perturbation method, the homotopy perturbation method, and the variational iteration method. Additionally, it has been discovered that this approach is a potent mathematical instrument that may solve a wide range of non-linear and linear issues that arise in various branches of technology and science, particularly some thermal transfer equations. It is demonstrated that for solving boundary value problems in engineering applications, the AGM approach is a superior substitute to semi-analytical and conventional numerical methods, mainly when the result's efficiency is crucial. [ABSTRACT FROM AUTHOR]

Friction Stir Welding, the solid-state technique has gained vantage in recent decades for welding dissimilar non-ferrous metals efficiently. Specifically, friction-welded Aluminium and Magnesium alloy joints are much desired in automotive and aerospace applications for their good specific strength. The dependency on additional filler materials or fasteners in conventional techniques deems them inapplicable and is also associated with solidification defects. The controlled heat generation and dissipation throughout the FSW process are often attributed to the resulting high joint strengths; which inquires the investigation of heat transfer during the operation. The present work deals with the analytical and numerical modelling of heat input for friction stir welding of AA 6061 and Mg AZ31B alloys and a comparison of the predicted results. The numerically simulated results are in good agreement with the developed analytical models and offer a good insight for predicting the characteristics of the FSW joints. [ABSTRACT FROM AUTHOR]

This study aims to investigate time-fractional transient heat and humidity transfer in nanocomposite media subjected to hygrothermal loadings. After each layer has been subjected to time-independent volumetric heat sources and hygrothermal loadings at the cylindrical surfaces, the resulting hygrothermal field is analyzed and characterized. In contrast to previous analytical research, even the effects of moisture on heat transport are ignored. When defining a temporal coupled issue, the presence of exact progression in dampness flux at layer interfacing holds on. This is the case even though moisture-induced effects on heat transfer are ignored. The analytical solution to the hygrothermal field can be obtained by employing a method of integral transformation, which is analogous to the Sturm-Liouville change for the composite region of k-layers by taking into account series extension function with eigenfunction to solve the partial differential equations. This allows the problem to be transformed into a form that can be solved analytically. The impact of moisture-flux progression at the layer interface on the dissemination of hygrothermal stretch is examined utilizing numerical reenactments for a three-layered structure, and the comes about are outlined graphically. [ABSTRACT FROM AUTHOR]