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The water bath is one of the laboratory equipment that serves to maintain the temperature of the water in the chamber. This chamber is used to soak reagents, incubate cells, and even melt substrates. Water heater calibration is a function feasibility test to determine whether the water bath is still suitable for use. Calibration is done by comparing the measuring instrument with the measuring material to be calibrated using national or international measuring standards. This article presents the research results on engineering a water bath calibrator using 8 channels whose measurement results can be displayed and saved to a CSV-type file via a smartphone application. The physical design is to place eight DS18B20 sensors at 8 different points in the water bath chamber to get the temperature value at each test point. The Atmega328P microprocessor processes the temperature detection results from the sensor and is then sent via the HC-05 Bluetooth module to the MIT App Inventor application, which is then displayed and stored in the android application. The measurement results of the calibrator prototype were compared with the measurement results of the national standard Multi-Channel Thermocouple Temperature Data Logger of the Madge-Tech brand. Analysis of the test results shows that the value of the test parameters at 8 points that appear through the smartphone application tends to increase with the same degree of increase as the value of the test results of the comparison tool. This fact proves that the thermodynamic phenomenon is in accordance with the working principle of this prototype and the working principle of data communication works well in this study. [ABSTRACT FROM AUTHOR]

Photovoltaic (PV) systems tend to be overcharged because they receive abundant solar energy, especially during the dry season. Therefore, this excess energy can be used for other purposes, such as heating water. PV systems that also generate thermal energy are called photovoltaic-thermal (PV/T). This paper aimed to design a PV system for small-scale households integrated with a water heater. The PV/T system was coupled with a thermal energy storage tank with a volume of 16 liters. The loads on the PV/T system were the water pump, heating elements, and lights. The first step in the design was to calculate the required load. It then performs technical calculations for the PV system components: solar modules, batteries, and charge controllers. The selection of solar modules uses a current-based concept. Total of the actual daily load of the PV/T system is 27.5 Ah/day. The design of the PV/T system produces specifications, namely solar modules with a nominal power of 50 Wp, as many as two, a battery capacity of 70 Ah, and a battery charge controller current of 10 A. [ABSTRACT FROM AUTHOR]

The essential radiant heating system component is a water heater so this study presents an experimental and numerical work of a water heater with an AC heating element powered by photovoltaic panels. The experimental work included a study of the thermal performance of a water tank under a constant ambient temperature and different supplied water temperatures. The impact of ambient temperatures of (290,292, and 294) K on the tank water temperature distribution under a constant supplied water temperature of 280K had been studied. Also, the stratification of water temperature is analyzed with the height of the tank. Numerical work studied the tank water temperature distribution with time for different supplied water temperatures of (280,285 and,290) K. Experimental work results have been utilized for developing and validating the numerical work results The comparison between experimental and numerical results appears good matching and the error does not exceed 3%. [ABSTRACT FROM AUTHOR]

Dual The electricity demand has increased fast in most parts of the world. Traditional power plants of fossil fuel energy sources produce electricity combined with environmental pollution, which makes it a necessity to search for alternatives and energy-conservative solutions. The Electric Water Heater (EWH) was recorded as the second biggest household energy consumption. One effective alternative for energy saving is to use hybrid Electric/Solar Water Heaters (ESWHs) instead of EWHs. Many kinds of research have focused on the efficiency and optimization of various kinds of solar water heater technologies, and few other studies have discussed the hybrid Electric/Solar Water Heater (ESWH) systems. However, there is a lack of modeling behavior of such types of water heaters. This work formulates the ESWH system and compares the modeled outcomes with the corresponding experimental measurements. The results obtained showed a great meeting between the proposed model and the measurements. [ABSTRACT FROM AUTHOR]

R32 refrigerant represents an alternative option to be used in heat pump water heaters because of the low operative pressure, nontoxicity and minor flammability level (A2), along with zero ODP and low GWP (675). This study contributes to the optimal selection of the refrigerant charge for commercial heat pump water heater application with a rated heating capacity of 4 kW. Experiments and simulations are conducted by varying mass charge (0.52 kg, 0.56 kg, 0.59 kg and 0.61 kg) with constant air temperature and humidity and water temperature. Consequently, the heat pump water heater will be evaluated in terms of the energetic performance and environmental footprint based on the LCCP analysis. The results demonstrate a maximum COP of 5.62 occurs at a mass charge of 0.61 kg. The LCCP analysis demonstrates reduced emissions in this condition when a representative case of specific water demand is considered. Simulations show accurate agreement with the experimental with an average maximum relative error less than 5%. [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]

This paper presents the design and development of a reliable tracking and recording system to monitor energy that has been consumed by electrical appliances. The electrical energy resources management is a major concern worldwide especially toward the waste of electricity. The current electrical energy monitoring system can only be viewed when attached to the device and it is more difficult to track all devices at one time. The energy production is depending on the energy management activities to minimize the environmental impacts. Therefore, we introduce the Electrical Energy Consumption Monitoring System over IoT, targeted to measure electrical energy for home appliances such as air conditioners, water heaters, fans, lighting and others. The monitoring system consists of an electrical current sensor and a Raspberry pi IV microcontroller as the main core. The system will measure energy based on the rate of current flowing through the cables of electrical equipment and subsequently the energy consumption can be calculated. The measured values can be accessed directly via computer or smartphone. These reading values are stored in a database for future reference and comparison. On the server, Node-Red, influxDB and Grafana were installed. The use of IoT technology allows the rate of electricity consumption to be monitored anywhere quickly and accurately even at a distance. [ABSTRACT FROM AUTHOR]

Expansion of the regulatory range for the supply of electricity at combined heat and power plants (CHPPs) is a very important task today. In winter, this becomes especially relevant. This problem can be solved by complete or partial bypass of network water heaters, the use of sliding pressure in the heat extraction and daily regulation of heat supply from the CHPPs [1]. Peak aggregates and installations are created. Here we consider such a flexible reserve as the expansion of the regulation range for the supply of electricity to CHPPs through the use of the storage properties of heat networks and buildings. At night (during the charging period), the electric power is reduced due to the supply of fresh steam from the boiler to the upper network heaters, or to an additional boiler unit (ABU). During the day (during the discharge period), the storage capacity of heating networks and buildings allows you to get additional electrical power by reducing the thermal power of the upper network heater. The criterion for evaluating the efficiency of using the storage properties of heat networks and buildings to expand the regulation range for the supply of electricity at CHPPs is the difference between the proceeds from the sale of electricity in the mode with accumulation and in the mode without accumulation, taking into account the costs of operating an additional pump at night in the mode with accumulation. To calculate the revenue from the sale of peak energy for these systems, the ranges of values for two-part and three-part rates were taken. The decrease in the production of thermal energy in the daytime by the heating plant should not violate the comfortable microclimate conditions in the heated premises. Calculations according to the method proposed earlier by the authors confirmed the observance of comfortable conditions in a heated room when using the storage properties of heating networks and buildings. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic has had a broad impact on various sectors of life, both social and economic, so that community groups at CITARA UKM develop bio floc catfish cultivation for food security. A good bio floc catfish cultivation is at a pond water temperature of 25-30°C. The problem is that at night, the temperature of the pond water drops below 25°C, so fish productivity is less than optimal. The purpose of this research is to design, manufacture, install and test a bio floc pond water heating system so that the temperature can be maintained at a minimum of 25°C, so that fish productivity can be optimal. The research method is an experimental method, carried out by designing, manufacturing, installing, and testing the installation of an automatic water heating system that utilizes gas-fired water heaters with a combination of solar cells as a supporting power source. The fish pond water heater system design consists of: solar panel 500 WP, submersible water pump 100 watt, a gas-fired water heater, copper pipe 3 m, switch and temperature monitoring system. The drawing of heater system installation conducted by Corel draw software. Testing the system installation is done by connecting the switch via the digital temperature controller STC 1000 so that the water pump turns on automatically because it is supplied with energized by the solar panel and turns on the water heater, thus heating the pool water which monitored automatically by the temperature monitoring system. The results showed that the bio floc fish pond water heater system can work well to maintain fish pond water at a temperature of 24,6 - 28°C with a heating time of 31 minutes. When the fish pond water temperature is < 25°C, the heater system automatically turns on, and when the fish pond water temperature reaches 28°C, the heater system automatically turns off. [ABSTRACT FROM AUTHOR]

Disruption of the control system and poor quality of water heaters due to problems with the steam water heating system on board, so the author took the initiative to design this teaching aid to find solutions to problems. Solar power generation is a system that can take advantage of abundant energy when sailing. Designing this teaching aid aims to find out how the system works, controls, and maintains it. The author uses the R&D method, namely research and development, procedures or steps for assembling a product development tool, either hardware or software. Then conduct a feasibility test of teaching aids through a questionnaire using the Guttman scale to find a firm answer YES or NO from the respondent. The feasibility value is calculated and the validity test. The respondents consisted of II, IV, VII and VIII semesters from the engineering department of PIP Semarang. From the results of the design of this teaching aid, it has two interconnected systems, namely the solar power generation system and Arduino as a remote control device, this module is programmable. It can be programmed according to the user's wishes. The author combines a temperature sensor and a Bluetooth module that functions as a transceiver and command receiver. The validity test results are valid because all item correlation values>0.466 Cleaning the panel and maintaining the battery water level is one thing that must be done. [ABSTRACT FROM AUTHOR]

Brunei is considered as one of the countries which are the highest consumers of electricity per capita in Asia. Most of the consumption is mainly for domestic purposes, which includes the use of a water heater. The water heater is mostly used for showering, washing, and cooking. A flat plate solar water heater was designed to provide the inhabitant with hot water that utilizes natural convection, which is known as the thermosiphon effect. A prototype of a solar water heater was constructed and tested for its functionality and performance. The experiment was done for ten days which was held from the end of March to early April 2021. The results from the experimental study have shown that the prototype was able to achieve a temperature within the range of 50°C to 67.2°C. In addition, it also achieved an instantaneous optimum rate of thermal output of 6.19 kW and a maximum average daily solar collector efficiency of 67.2%. [ABSTRACT FROM AUTHOR]

The influence of vibrations of a solid surface on the hydrodynamic regime of the generated flow was considered. Experimental studies showed that when the vibration intensity exceeds a certain level determined by the Reynolds number, a steady flow of liquid is formed near a solid surface. The flow can reduce the local overheating of the heat transfer surface and, thereby, reduce the rate of formation of salt deposits during the heating of hard water. [ABSTRACT FROM AUTHOR]

The influence of solid surface vibrations on the performance of heat and mass transfer processes in an aqueous medium is studied. In the course of experimental investigations, a mathematical expression was obtained that makes it possible to evaluate the influence of the frequency and amplitude of surface vibrations on the performance of considered process. We developed the construction of an electric heater with a vibrating solid surface, which makes it possible to heating water with a high concentration of hardness salts. [ABSTRACT FROM AUTHOR]

At present is a demand to produce industrial steam turbines intended for factory applications. A very common requirement is to keep constant parameters in turbine extraction. Pressure in uncontrolled bleed depends on turbine load. Therefore, it is used nozzle with moveable leading edges to control pressure inside turbine extraction. Nozzle with movable leading edges can reduce mass flow to the condenser or district water heater and it causes pressure increase upstream the nozzle. There can be used internal extraction valve to control steam amount into rear part of turbine as an option. Steam from extraction is then used in other technologies such as a paper mill, sawmill etc. There is an effort to simplify balance of turbine and reduce price as low as possible. Therefore, an effort is to check the need of safety valve including pipeline discharge leading out of machine hall, supports and hangers. The safety valve is located at pipeline extraction to prevent pressure increase above design parameters in case of any system malfunction. This article deals with introduction to this issue and the discovery of possible solutions how determine the maximum pressure increase in controlled turbine extraction. [ABSTRACT FROM AUTHOR]

Air Conditioner Water Heater (ACWH) is a technique of recovering generated Heat Waste within refrigerant cycle on a running Air Conditioning System. Heat transfer occurs from high-temperature refrigerants after exiting the compressor outlet to the water which has a lower temperature in water storage tank. With this transfer of heat, it is expected to decrease the refrigerant temperature and increase the temperature of the water inside the storage tank. There are several specific studies regarding ACWH design. Specifically, in University of Indonesia (UI), the previous studies and researches on ACWH design were only focused on investigating the performance of each Heat Exchanger design. This research was carried out on a Hybrid Design focusing on the water temperature output. Although the design of Heat Exchanger used (Serpentine Heat Exchanger) in this system was still the same used in the latest ACWH studies conducted in UI, there are several key differences in the Hybrid ACWH system. First, the water in the storage tank has been pre-heated beforehand with the help of Solar Heat Collector. Thus, this method should expect a higher final value of water temperature and should provide a backup solution when the AC system is not running, fulfilling the need of hot water availability at any time. The second difference in this H-ACWH system, the water storage tank is designed to have a space filled by PCM material between the outer shell of the tank and Aluminum Foil. The purpose of this implementation of PCM, along with the conventional insulation technique, is to further conserve the heat inside the tank by recovering possible heat loss with the latent heat of the PCM. The third difference is that in this H-ACWH system, there will be no electric water pump regulating water flowrate. This system will only rely on gravitational water. The results obtained in this study are expected to be higher final Hot Water temperature, a reliable Hot Water source system that can be implemented into Net Zero Energy Building concept as the system does not need any additional fossil or electric energy to run. [ABSTRACT FROM AUTHOR]

The research discusses a study and analysis of the system on the Air Conditioner (AC) which is engineered into two functions, namely air conditioning and hot water supply for bathing needs. Heat exchangers as water heaters that were be used capillary pipes, finned capillary pipes, honeycomb-shaped channels made of aluminum and brass. The aim of the study was to see the performance of AC (coefficient of performance/COP) due to the addition of a heat exchanger. The research was carried out experimentally with an experiment at an AC evaporator temperature of 16 0C with a duration of 60 minutes. The experimental results were used as initial data for calculating the COP value. The result, it was known that there was a decrease in AC performance when a heat exchanger application was added to the AC system. The largest decrease occurred in the type of honeycomb-shaped channel made of aluminum, from the COP value of 3.052 to 1.385. While the lowest decrease in COP occurred in the capillary tube heat exchanger type from 3.052 to 2.7. In addition, all the heat exchangers used could increase the temperature of the water in the tank and cause a decrease in the performance of the air conditioner itself. [ABSTRACT FROM AUTHOR]

The R&D of thermal-hydraulics for passive cooling system to optimize thermal management during the accident and operation of NPP become an important research topics related to the improvement of the accident management of NPP. The need for experimental research using medium scale test facilities becomes an important need to investigate passive cooling systems for improved reactor safety. FASSIP-01 Loop is a medium scale test facility which water inside the rectangular loop which the water flow is driven by natural circulation due to the differences of density in heater area and in the cooler area. The purpose of this experiment is to investigate the natural circulation phenomenon during start-up condition since the beginning until stable flow. The experiment has been done with heater power variation is 4845 watt and 5928 watt, the flow rate variation in cooler area is 10.38 LPM and 43.10 LPM with the pipe of rectangular loop was not isolated. The result of experiment from 0 s to 5000 s shows the backward phenomenon which was occurs due to decrease in water temperature near the pipe wall. The backward flow point difference between two heater powers is 0.0165 LPM for coolant flow of 10.38 LPM and 0.0088 LPM for coolant flow of 43.10 LPM. The density of water in cross section of rectangular pipe is not the same for a few times. [ABSTRACT FROM AUTHOR]

In this paper the authors present an unusual method for bottom forming applicable for various industrial purposes including the manufacture of water heaters or pressure equipment. This method allows for the fabrication of the bottom of a given piece of stainless steel into a pre-determined shape conforming to the DIN standard which determines the most advantageous dimensions for the bottom cross section in terms of working pressure loading. The authors checked the validity of the method in a numerical and experimental way generating a tool designed to produce bottoms of specified geometry. Many problems are encountered during the design and production of parts, especially excessive sheet wrinkling over a large area of the part. The experiment showed that a lack of experience and numerical analysis in the design of such elements would result in the production of highly wrinkled parts. This defect would render the parts impossible to assemble with the cylindrical part. Many tool shops employ a method for drawing elements with a spherical surface which involves additional spinning, stamping, and grading operations, which greatly increases the cost of parts production. The authors present and compare two forming methods for spherical and parabolic objects, and experimentally confirm the validity of the sheet reversing method with adequate pressure force. The applied method produces parts in one drawing operation and in a following operation that is based on laser or water cutting to obtain a round blank. This reduces the costs of tooling manufacturing by requiring just one tool which can be placed on any hydraulic press with a minimum force of 2 000 kN. [ABSTRACT FROM AUTHOR]

The present experimental evaluation has been carried out to investigate the use of capillary tube (CT) and thermostatic expansion valve (TEV) with heat recovery hot spot water heater (HRHSWH) in air source compression refrigeration system. CT and TEV are the two basic types of refrigerant expansion devices that most frequently used in compression refrigeration system, but the identified about HRHSWH in extant literature are limited. The HRHSWH is modified from residential refrigeration system. The heat exchanger coil as HRHSWH was bonded with the compressor discharge pipe line as counter-flow heat exchanger, then insulated and placed them into transparent acrylic box. Water from storage tank with 50L capacity is pumped using circulation pump to the HRHSWH and heating the water in storage tank. The system performance of those two expansion devices in compression refrigeration system are evaluated and compared between with or without modified using HRHSWH. Results show that refrigeration system using TEV performs better performance than CT using HRHSWH compared to standard refrigeration system (without HRHSWH). The use of TEV device in HRHSWH causes a slight decrease in compressor power 0.0198 kW (4%), where the COP increases around 20% higher than the CT device. The finding indicates that the use of HRHSWH generates free hot water for TEV and CT with temperature around 54.06°C and 55.78°C, respectively. In general, HRHSWH give better perfomance than standar refrigeration system. [ABSTRACT FROM AUTHOR]

The present experimental evaluation has been carried out to investigate the use of capillary tube (CT) and thermostatic expansion valve (TEV) with heat recovery hot spot water heater (HRHSWH) in air source compression refrigeration system. CT and TEV are the two basic types of refrigerant expansion devices that most frequently used in compression refrigeration system, but the identified about HRHSWH in extant literature are limited. The HRHSWH is modified from residential refrigeration system. The heat exchanger coil as HRHSWH was bonded with the compressor discharge pipe line as counter-flow heat exchanger, then insulated and placed them into transparent acrylic box. Water from storage tank with 50L capacity is pumped using circulation pump to the HRHSWH and heating the water in storage tank. The system performance of those two expansion devices in compression refrigeration system are evaluated and compared between with or without modified using HRHSWH. Results show that refrigeration system using TEV performs better performance than CT using HRHSWH compared to standard refrigeration system (without HRHSWH). The use of TEV device in HRHSWH causes a slight decrease in compressor power 0.0198 kW (4%), where the COP increases around 20% higher than the CT device. The finding indicates that the use of HRHSWH generates free hot water for TEV and CT with temperature around 54.06°C and 55.78°C, respectively. In general, HRHSWH give better perfomance than standar refrigeration system. [ABSTRACT FROM AUTHOR]

This paper is focused on the research of gravitational heat pipes for heat recovery for hot water heating from the flue gas in small biomass heat sources. The paper includes a proposal of an experimental device, with the help that is explored the influence of the amount of water filling at various temperature parameters (heating temperature and temperature cooling) on transferred heat performance by gravitational heat pipe. There is also introduced in a measuring procedure for heat pipe by using the proposed experimental device and measurement results. Due to the similarity of the experimental measurements with the prototype for heating of hot water in small combustion heat sources' the heating of heat pipe is made by hot air and the cooling on the condenser section of heat pipe is carried out with water. At the end of the article is an analysis of the obtained results which are compared to the numerical model. Based on the results obtained from experimental measurements would be possible to design a prototype of water heater' which uses a gravity heat pipe for heat transport. The heat pipe would safely heat the water in a storage tank by flue gas in the flue gas duct of the small heat sources using biomass fuel. [ABSTRACT FROM AUTHOR]

For a CO2 heat pump water heater, one-stage twin rotary compressor has been designed. As a design tool, computer simulation program for the compressor performance has been made. Validation of the simulation program has been carried out for a bench model compressor in a compressor calorimeter. Cooling capacity and the compressor input power were reasonably well compared between the simulation and the calorimeter test. Good agreement on P-V diagram between the simulation and the test was also obtained. With this validated compressor simulation program, parametric study has been performed to arrive at optimum dimensions for the compression chamber. [ABSTRACT FROM AUTHOR]