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1
Mar’ina, Z. G., A. Y. Vereshchagin, A. V. Novozhilova, M. A. Komarevtsev, and K. O. Isaeva. "Study of the thermal characteristics of the aluminum radiator ROYAL Thermo Evolution." IOP Conference Series: Materials Science and Engineering 1211, no. 1 (January 1, 2022): 012005. http://dx.doi.org/10.1088/1757-899x/1211/1/012005.
Повний текст джерелаАнотація:
Abstract The use of aluminum radiators in heating systems began with the foreign companies products such as Fondital Group, Global Radiatori, Ferroli, etc. There are now Russian aluminum radiators companies that adhere to European standards, for example ROYAL Thermo, Rifar. The thermal characteristics of radiators are usually specified by the manufacturer. However, they are not always confirmed in practice. This is due to the fact that radiator connecting method is not taken into account. In some technical data sheets, the power reduction factors are given depending on the difference between the average coolant temperature and the air temperature in the room. Therefore, the study of the influence of aluminium heating appliances connecting on its thermal characteristics is an actual task. The article presents the results of research of radiator of the ROYAL Thermo Evolution type, it was made on request from company specialising in heating systems design. It was found that the actual thermal power of one section varies in the range of 135 … 225 W, depending on the connection method of the radiator, the thermal power of the section declared by the manufacturer corresponds only to the diagonal «top-bottom» connection, the thermal power of the eight-section radiator with one-sided «top-bottom» connection is 12% higher than with a diagonal one. Studies show, when designing heating systems, it is necessary to take into account the connection method and the number of device sections.
2
Shui-Chang, Liu, Li Li-Fu, and Zhang Yong. "Vehicle Radiators’ Performance Calculation and Improvement Based on the Coupling of Multi-scale Models Simulations." Open Mechanical Engineering Journal 8, no. 1 (December 31, 2014): 636–42. http://dx.doi.org/10.2174/1874155x01408010636.
Повний текст джерелаАнотація:
In simulation of the heat transfer between radiator and air flow field, the adoption of the radiator full-size model containing its core body structure with small feature sizes would require huge storage space and not be economical. In view of this question, based on the coupling of multi-scale models simulations, a calculation method of radiator performance is proposed in this paper the reliability of which is verified by an experiment test. Subsequently, the influence on the radiators’ thermal performance of the layout of the parts in front of the radiators is analyzed. Lastly, the layout of the front parts is modified to enhance the radiators’ thermal performance. The investigation results indicate that: the radiators’ thermal performance calculation method based on simulations coupling of radiator multi-scale models considers the influences of air-side flow field distribution and the core body structure details; the error of the calculating values from the method is less than 5%, and the method is reliable; when the heat source parts in front of the radiators are situated right in front of the rear fan channel, the radiators thermal performance is better; the radiators cooling power increases 19.3kW after layout modification of the front heat resource parts.
3
Sravan, Venapusa, Himani Srivastava, Pandey DHANRAJ Jitendra, and S. Senthur Prabu. "Investigation on Thermal Analysis of Spacecraft Radiators." ECS Transactions 107, no. 1 (April 24, 2022): 17073–83. http://dx.doi.org/10.1149/10701.17073ecst.
Повний текст джерелаАнотація:
In this research, the main objective is to compare the thermal properties of the rectangular and honeycomb structured space radiators used in spacecraft. The comparison of radiators was done by conducting steady state thermal analysis on these radiators by applying varying heat loads over it to analyse the thermal properties acting over them. The selection of appropriate material for the radiators was based on tensile strength, resistance to high temperature, and the type of working fluid considered. From the simulation results, the honeycomb structures of spacecraft radiator could withstand to a higher temperature gradient, and the rate of heat dissipation was much higher in comparison with rectangular fin type radiator, and hence it can be considered as a great replacement in near future.
4
Chen, Liguo, and Bjørn Reidar Sørensen. "Modelling Multi-layer Hydronic Radiators." E3S Web of Conferences 172 (2020): 12007. http://dx.doi.org/10.1051/e3sconf/202017212007.
Повний текст джерелаАнотація:
This report simulates Purmo type C22 and C33 radiators with both standard calculation and heat transfer method with help of Matlab/Simulink. Simulation results are presented to describe the radiators’ thermal performances with different simulation strategies. The deviations between two different calculation methods are identified and the heat transfer radiator model can be improved with more investigations regarding thermal dynamics and controlling strategy. Under simulation scenarios of simple room model with a PID controller, type C33 has shorter response time and faster stabilization of room temperature; and it has lower outflow temperature, which implies higher energy efficiency.
5
Šikula, Ondřej, Pavel Charvát, Lahouari Adjlout, and Omar Ladjedel. "Modeling of Radiators with Mass Flow Control." Applied Mechanics and Materials 887 (January 2019): 667–75. http://dx.doi.org/10.4028/www.scientific.net/amm.887.667.
Повний текст джерелаАнотація:
The topic of the contribution can be included in computer modeling of the thermal behavior of radiators for heating of buildings. Control of heaters leads to dynamic phenomena affecting the final thermal state of the heated room and heating energy consumption. The paper focuses on modeling of radiator quantitative control method using thermostatic valve. The objective of the paper is to show a quality of controlling and to compare an energy consumption when various thermostatic radiator valves time delay are set. The models of control, radiator, and a room are implemented in software TRNSYS. The results show significant differences in energy consumption.
6
Hao, Gai Hong, and Ya Ping Zhang. "Thermal Performance Simulation of the Metal Foam Heat Sink." Solid State Phenomena 298 (October 2019): 208–13. http://dx.doi.org/10.4028/www.scientific.net/ssp.298.208.
Повний текст джерелаАнотація:
This study investigated the sintered metal among the regular finned heat sink. And a metal foam heat sink for power module cooling is designed. An improved computational model for effective thermal conductivity was obtained. Contrast to the two types of the heat sink, it is found that under the condition of the constant heat flow density, the heat accumulated is absent in metal foam heat sink. Meanwhile, the heat transfer coefficient of the metal foam heat sink is 3.6 times that of the finned heat sink of equivalent geometric parameter. At the same drop pressure, the air velocity of the metal foam heat sink is lower than that of the finned heat sink. The velocity of air in the foam radiator is lower than that in the finned radiator. Under the same fan power, the gain factor of the four finned metal foam radiators is about 20 times higher than that of the ribbed radiators of the same conditions.
7
Kroulíková, Tereza, Tereza Kůdelová, Erik Bartuli, Jan Vančura, and Ilya Astrouski. "Comparison of a Novel Polymeric Hollow Fiber Heat Exchanger and a Commercially Available Metal Automotive Radiator." Polymers 13, no. 7 (April 6, 2021): 1175. http://dx.doi.org/10.3390/polym13071175.
Повний текст джерелаАнотація:
A novel heat exchanger for automotive applications developed by the Heat Transfer and Fluid Flow Laboratory at the Brno University of Technology, Czech Republic, is compared with a conventional commercially available metal radiator. The heat transfer surface of this heat exchanger is composed of polymeric hollow fibers made from polyamide 612 by DuPont (Zytel LC6159). The cross-section of the polymeric radiator is identical to the aluminum radiator (louvered fins on flat tubes) in a Skoda Octavia and measures 720 × 480 mm. The goal of the study is to compare the functionality and performance parameters of both radiators based on the results of tests in a calibrated air wind tunnel. During testing, both heat exchangers were tested in conventional conditions used for car radiators with different air flow and coolant (50% ethylene glycol) rates. The polymeric hollow fiber heat exchanger demonstrated about 20% higher thermal performance for the same air flow. The efficiency of the polymeric radiator was in the range 80–93% and the efficiency of the aluminum radiator was in the range 64–84%. The polymeric radiator is 30% lighter than its conventional metal competitor. Both tested radiators had very similar pressure loss on the liquid side, but the polymeric radiator featured higher air pressure loss.
8
Kushwah, Pavan. "Review on Thermal Analysis of Automobile Radiator." International Journal for Research in Applied Science and Engineering Technology 9, no. VII (July 31, 2021): 3758–66. http://dx.doi.org/10.22214/ijraset.2021.37186.
Повний текст джерелаАнотація:
Radiators are used to transfer thermal energy from one medium to another for the purpose of cooling. Low efficiency heat exchangers used in automotive as radiator may cause to serious dangers for the engine. Hence, thermal scientists and engineers always pursuit modern methods to enhance the heat removal of the engine. It seems nanofluids implementation in automotive cooling system promises to achieve high efficiency radiators. This paper reviews almost all performed studies in this area that are available in the literature. Author collects details about nanoparticles materials and size, base fluid, volume, concentration, flow regime and Reynolds number used in studies. Usually, maximum heat transfer enhancement and maximum need of pumping power that occurs at the highest volumetric concentration of nanoparticles, simultaneously. On the other hand, using nanofluids, due to the enhanced heat carrying capacity of the nanofluids; the pumping power required will also be reduced.
9
Huang, Haibo, Xiaohua Huang, Zaijun Cheng, and Yuanzhang Wang. "Simulation study of nanomaterials in heat pipe enhanced high power LED heat sink." Journal of Physics: Conference Series 2535, no. 1 (June 1, 2023): 012021. http://dx.doi.org/10.1088/1742-6596/2535/1/012021.
Повний текст джерелаАнотація:
Abstract To facilitate the simulation of heat dissipation of high-power LED lamps, a set of simplified models for tubular heat pipes and carbon nanotube arrays were first established to estimate their thermal conductivity. Then several kinds of radiators were designed. The application of nanomaterials and heat pipes in the heat dissipation of lamps was studied by the finite element method. It is found that the radiator with vertical suspended fins strengthened by a heat pipe and heat dissipation coating has a better heat dissipation effect than other radiators. Finally, the simulation study of thermal interface materials and heat dissipation coatings for lamps and lanterns heat dissipation is carried out. The results show that the thermal interface materials of carbon nanotubes and carbon nano coatings can enhance the heat dissipation performance of lamps.
10
Võsa, Karl-Villem, Andrea Ferrantelli, and Jarek Kurnitski. "Assessment of downward draught in high-glazing facades in cold climates – experimental and CFD study into draught control with a 21-type radiator." E3S Web of Conferences 246 (2021): 02002. http://dx.doi.org/10.1051/e3sconf/202124602002.
Повний текст джерелаАнотація:
This paper investigates the interaction of a radiator’s thermal plume and downdraught of cold glazed surfaces. Draughts in working areas are one of the most common thermal comfort complaints in modern buildings. A typical solution for dealing with these draughts is positioning the heat emitters such as radiators or convectors under the windows. However, with thermally efficient envelopes, the internal loads compromise a relatively high fraction of the heating demand and the emitters are working under partial loads in modern buildings. This study comprises two parts: an experimental phase in the EN442 standardized test chamber with a 21-type radiator, and a CFD simulation phase, where the model is validated and applied under an expanded set of boundary conditions. The expanded simulation set results provide preliminary insight into sizing and design. More specifically, the thermal plume can be parametrised with a velocity and temperature value along with the room air and glazing temperatures for a broader analysis and assessment of the risk of draught.
11
Zhang, Zhong Lin, Qian Hui Gang, Peng Qiu, Shu Han Wang, and Cong Yu Bai. "A Study on Performance Test of the Self-Cooled System of High-Voltage SVC Valve Group." Applied Mechanics and Materials 713-715 (January 2015): 1322–24. http://dx.doi.org/10.4028/www.scientific.net/amm.713-715.1322.
Повний текст джерелаАнотація:
The high-voltage SVC realizes the dynamic reactive power compensation through the real-time control over the breakover and cut-off of thyristor. Because the current passing through thyristor is large, the frequent break-make will lead to a lot of thermal loss, so it should be cooled in time. The self-cooled heat pipe cooling system is a traditional high-voltage SVC cooling system, which is expensive and heavy because it adopts relatively expensive copper product and aluminium product.This paper introduces a new heat pipe radiator. Compared to the traditional heat pipe radiators, it is light in weight, small in volume and low in cost. The performance test shows that the thermal resistance of the radiator is 0.064°C/W, that the main performance indexes are superior to those of the similar heat pipe radiators at home and abroad and that its self-cooling ability has achieved a high level. Therefore, it will greatly promote the promotion and application of this technology in China.
12
Trofimov, V. E., A. L. Pavlov, and A. S. Storozhuk. "CFD-simulation of impact jet radiator for thermal testing of microprocessors." Технология и конструирование в электронной аппаратуре, no. 5-6 (2018): 30–36. http://dx.doi.org/10.15222/tkea2018.5-6.30.
Повний текст джерелаАнотація:
One of the final stages of microprocessor development is thermal testing. This procedure is performed on a special stand, the main element of which is a switching PCB with mounted microprocessor sockets, chipsets, interfaces, jumpers and other components which provide various modes of microprocessor operation. Changing the case temperature of the microprocessor is carried out typically using a thermoelectric module. The cold surface of the module with controlled temperature is in direct thermal contact with the microprocessor housing designed for cooler installation. On the hot surface of the module, the radiator is mounted which dissipates the total heat flux from the microprocessor and the module. High density PCB layout, the requirement of free access to the jumpers and interfaces, and the presence of numerous sensors restrict the space for radiator mounting and require the use of an extremely compact radiator, especially in air cooling conditions. One of possible solutions for this problem may be to reduce the area of the heat-transfer surfaces of the radiator due to a sharp growth of the heat transfer coefficient without increasing the air flow rate. A sharp growth of heat transfer coefficient of the radiator can be achieved by making several conic or combined conic-cylindrical dead-end cavities with extra finning in the heat-transfer surface. Such cavities should absorb the impact air jets. In this study, CFD simulation of such radiators has been conducted. It is determined that when the air velocity at the nozzle entrances is 50—100 m/s, the investigated designs of impact-jet radiators have a thermal resistance in the range of 0.5—2.2°Ñ/W. This is quite sufficient for the thermal testing of some types of microprocessors with setting a number of operational modes and performing of certain types of test computations. It is shown that the use of combined dead-end cavities with extra finning is the best of the considered solutions and allows for a sharp (up to 44%) intensification of heat transfer in the radiator in comparison with cylindrical dead-end cavities, but at a cost — the loss of air pressure increases up to 20%. As a result of the study, it was found that the impact-jet radiator with dead-end tapering cone shaped cavities and combined cone-cylinder shaped cavities with extra finning, can successfully solve the problem of heat removal from microprocessors during thermal testing. However, it should be noted, that such radiators have a high aerodynamic resistance and require a high pressure air source for operation.
13
Han, Ying, Zhi-jun Liu, Chun-guang Hou, Yun-dong Cao, and Li-rong Zhai. "Thermal analysis of electric vehicle DC charging pile power module based on two-dimensional ordered porous structure radiator." E3S Web of Conferences 213 (2020): 03016. http://dx.doi.org/10.1051/e3sconf/202021303016.
Повний текст джерелаАнотація:
In order to improve the heat dissipation performance and study the factors affecting the heat dissipation effect of a two-dimensional ordered porous structure, a thermal analysis of the radiator in the power module of a DC charging pile was carried out. Based on the thermal analysis of the grid-type radiator, the square-hole radiator is subjected to a thermal analysis, the heat dissipation performance of the two radiators is compared, and the factors affecting the heat dissipation effect of the square-hole radiator are explored. Research shows that the heat dissipation effect of the square-hole radiator, which represents a twodimensional ordered porous structure, is better than that of the grid-type radiator. The factors affecting the heat dissipation effect of the square-hole radiator are mainly related to the height of the radiator and are positively related to the heat dissipation effect of the radiator.
14
Ahmed, Zakariya, and Akanksha Mishra. "Heat Transfer Enhancement of Radiators Using Various Approaches: Review." International Journal of Advance Research and Innovation 6, no. 2 (2018): 69–82. http://dx.doi.org/10.51976/ijari.621811.
Повний текст джерелаАнотація:
This paper reviews heat transfer enhancement of radiators using different approaches. It has been found that different method of heat transfer augmentation has been employed in different radiator design. These methods ranging from fin design modification, increasing core depth of radiator, change of tubes type, increasing surface area of radiator core, change of fin material, change of flow arrangement and changing the different types of fluid and mixture concentration. The performance of a radiator depends on its thermal and hydrodynamic performance. Certain parameters are of importance to the radiator performance such as; convective heat transfer co-efficient, pressure drop, inlet and outlet coolant temperature, air and coolant mass flow-rates, fin type, fin dimension and material. The various approaches are considered, depending on the application requirement and utilizing range. Radiator design modification such as increase in number of fins and tubes, material substitution have their limitations with certain negative consequences like added cost and weight with low efficient thermal performance compare to utilization of Nano-fluid approach. The engine life and its performance depend on coolant temperature. The application of nano-fluid in automobile radiator as coolant greatly affects the performance of the engine which in turn enhances its life span and fuel consumption. This paper attempts to review literature related to various heat transfer enhancement methods in vehicle radiator with different design, and compares the most effective approach amongst the methods taking into consideration cost, weight and thermal efficiency.
15
Han, Yue, Ya Jun Zhang, Da Ming Wu, Jian Zhuang, and Kai Fang Dang. "Optimal Design of Micro Plastic Heat Radiator." Key Engineering Materials 503 (February 2012): 67–70. http://dx.doi.org/10.4028/www.scientific.net/kem.503.67.
Повний текст джерелаАнотація:
A new type of plastic micro heat radiators is designed in this paper. The radiator is prospected to be used in electronic system, chemical engineering system, etc. It is made of modified Phenylene sulfide with high thermal conductivity. A series of numerical simulations are carried out to optimize the structure of the radiator. The structure of the radiator includes the thickness of the fin and the distance between fins. The results show that the performance of the micro plastic heat radiator is very close to that of the metal heat radiator with the same dimension.
16
Canazas, José, and Oleg Kamyshnikov. "Heat Transfer and Pressure Drop Performance of a Hydraulic Mining Shovel Radiator by Using Ethylene Glycol/Water-Based Al2O3 Nanofluids." International Journal of Heat and Technology 40, no. 1 (February 28, 2022): 273–81. http://dx.doi.org/10.18280/ijht.400132.
Повний текст джерелаАнотація:
Nanofluids are excellent replacements for vehicle radiator coolants and they have the ability to significantly enrich the performance of vehicle radiators. A numerical study of thermal and hydraulic performance of a hydraulic mining shovel radiator working with nanofluids is carried out. It is observed so far that there are no research works done before analyzing the radiator of this mining equipment. Aluminum oxide in ethylene glycol as nanofluid with volume concentrations of 0.5%, 1.0% and 1.5% were investigated. The results showed that the heat transfer performance of the radiator can be hindered if thermal operating parameters of the equipment are not varied to take advantage of the benefits done by nanofluids. Additionally, it has been found that the pressure drop performance on the radiator operating in laminar and transitional conditions can reduce pressure drop and therefore pumping power. The analysis presented in this paper concluded that the use of nanofluids essentially depends on thermal and flow conditions.
17
Pungaiah, Sudalai Suresh, and Chidambara Kuttalam Kailasanathan. "Thermal Analysis and Optimization of Nano Coated Radiator Tubes Using Computational Fluid Dynamics and Taguchi Method." Coatings 10, no. 9 (August 20, 2020): 804. http://dx.doi.org/10.3390/coatings10090804.
Повний текст джерелаАнотація:
Automotive heat removal levels are of high importance for maximizing fuel consumption. Current radiator designs are constrained by air-side impedance, and a large front field must meet the cooling requirements. The enormous demand for powerful engines in smaller hood areas has caused a lack of heat dissipation in the vehicle radiators. As a prediction, exceptional radiators are modest enough to understand coolness and demonstrate great sensitivity to cooling capacity. The working parameters of the nano-coated tubes are studied using Computational Fluid Dynamics (CFD) and Taguchi methods in this article. The CFD and Taguchi methods are used for the design of experiments to analyse the impact of nano-coated radiator parameters and the parameters having a significant impact on the efficiency of the radiator. The CFD and Taguchi methodology studies show that all of the above-mentioned parameters contribute equally to the rate of heat transfer, effectiveness, and overall heat transfer coefficient of the nanocoated radiator tubes. Experimental findings are examined to assess the adequacy of the proposed method. In this study, the coolant fluid was transmitted at three different mass flow rates, at three different coating thicknesses, and coated on the top surface of the radiator tubes. Thermal analysis is performed for three temperatures as heat input conditioning for CFD. The most important parameter for nanocoated radiator tubes is the orthogonal array, followed by the Signal-to-Noise Ratio (SNRA) and the variance analysis (ANOVA). A proper orthogonal array is then selected and tests are carried out. The findings of ANOVA showed 95% confidence and were confirmed in the most significant parameters. The optimal values of the parameters are obtained with the help of the graphs.
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Dzelme, Valters, Jevgenijs Telicko, and Andris Jakovics. "Thermal Comfort in Indoor Spaces with Radiant Capillary Heaters." Environmental and Climate Technologies 26, no. 1 (January 1, 2022): 708–19. http://dx.doi.org/10.2478/rtuect-2022-0054.
Повний текст джерелаАнотація:
Abstract Capillary heat exchangers are a great alternative to conventional radiators or electric heaters when used with heat pumps due to larger area and therefore a lower working temperature. In this work, we study thermal conditions in a model room using either capillary or conventional heaters. Experimental measurements in a special test building are used to validate and adjust numerical models. The results show that the vertical temperature distribution is similar with both heating systems, but air flow velocities are considerably higher and floor temperature is less uniform in case of radiator heating. Overall, the capillary system provides more uniform thermal conditions.
19
Arslanturk, Cihat. "Optimization of space radiators accounting for variable thermal conductivity and base-to-fin radiation interaction." Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering 232, no. 1 (October 13, 2016): 121–30. http://dx.doi.org/10.1177/0954410016673091.
Повний текст джерелаАнотація:
Space radiators used in aerospace applications are required to have a minimum weight, for the desired heat transfer rate. To ensure that the radiator has an optimal geometry, it is important that the heat transfer rate be calculated accurately. To obtain the heat transfer rate from the radiator accurately, the radiative interaction between the fin surface and fin base and the variation of thermal conductivity with temperature should be included in the analysis. Taking into account these two phenomena, this study was conducted in order to explore the optimal dimensions of a space radiator. The dimensionless nonlinear and nonhomogeneous fin equation is solved using the variation of the parameters method for carrying out the required optimization procedure. The optimization results are presented as convenient correlation equations for suitable ranges of problem parameters.
20
Qu, Sheng Guan, Li Kui Liu, Gang Li, and Xiao Qiang Li. "Cold Extrusion Forming Aluminum Alloy Honeycomb Radiator Mold Structure Optimization." Advanced Materials Research 904 (March 2014): 15–19. http://dx.doi.org/10.4028/www.scientific.net/amr.904.15.
Повний текст джерелаАнотація:
The quality of the honeycomb radiator structure has a great impact on thermal performance of the LED lamp. In order to make honeycomb radiators structure more uniform and materials fluidity much better; we firstly take use of cold extrusion to form the honeycomb radiator, then it will be machined. In the honeycomb radiator deformation than the larger places where prone to stress concentration, that has a seriously affect on the effect of the radiator forming. Therefore, we optimized the extrusion die, including upper and lower mold prone to stress concentration places create fillet. The results show that an appropriate fillet of the mold can greatly improve the forming uniformity and reduce the force on the die.
21
Benakopoulos, Salenbien, Vanhoudt, and Svendsen. "Improved Control of Radiator Heating Systems with Thermostatic Radiator Valves without Pre-Setting Function." Energies 12, no. 17 (August 21, 2019): 3215. http://dx.doi.org/10.3390/en12173215.
Повний текст джерелаАнотація:
Low-temperature district heating will play an important role in a future free of fossil fuels. This will only be able to be realized through the low-temperature operation of heating systems in existing buildings. Existing radiator systems can operate with low temperatures for most of the year because they are designed for extremely cold days, but errors have to be corrected and the control of the radiator systems needs to be improved. In this paper, we present a strategy to achieve low-temperature operation from the radiator system of a multi-family building in Denmark without a pre-setting function in the thermostatic radiator valves. The strategy is based on operating the system with a combination of a minimum supply temperature and small temperature differences over the radiators. The operation of the system is analyzed through a thermal-hydraulic model. A minimum supply temperature weather compensation curve was calculated and implemented in the central supply temperature control. Return temperature measurements in the substation, the risers, and several critical radiators were performed before and after the implementation of the strategy. The measurements confirm that a lower supply temperature results in a reduction of the return temperature. However, the system operator needs to be supported by a tool package to correctly maintain the system’s operation.
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Ivashina, Yu, and V. Zavodyannyi. "INSTALLATION FOR DETERMINATION OF HEAT RELEASE OF HEATING RADIATORS." Municipal economy of cities 4, no. 164 (October 1, 2021): 77–81. http://dx.doi.org/10.33042/2522-1809-2021-4-164-77-81.
Повний текст джерелаАнотація:
To calculate the share of thermal energy consumed by this apartment in an apartment building, it is necessary to determine the heat transfer of all heating radiators in the house. But the heat transfer given in the passport of the heating device corresponds to the temperature pressure equal to 70K. Often the owners install non-standard devices, so the problem of determining the heat transfer of heating radiators in real conditions is relevant. Thermometric method, which is called electric, is widely used for laboratory determination of heat transfer of heating devices. Water by means of the pump circulates through an electric copper and the investigated radiator. The heat output of the latter is defined as the difference between the supplied electrical power (boiler power plus pump) and heat loss. The purpose of the work is to develop and study the operation of the installation for determining the heat transfer of heating radiators, which had a simpler design and could ensure proper measurement accuracy. We have proposed a scheme and design of the installation for determining the heat transfer of electric heating radiators, which differs in that it does not include a circulating pump. Water in the system circulates under the action of gravity due to changes in the density of the coolant during heating and cooling. This greatly simplifies the circuit by eliminating not only the pump but also the valve and the air outlet valve. The heater chamber is made of a steel pipe with a diameter of 88 mm. A steel cover is attached to the lower flange, through which a 1-1.5 kW heater is introduced into the chamber. Two 1/2 ″ sections of pipe are welded to the body of the heater chamber, through which the radiator is connected by means of rubber couplings. The cylindrical surface of the chamber on top of the layer of internal insulation is covered with a shielding heater, the temperature of which is maintained equal to the surface temperature of the heater chamber in the middle part. A layer of external thermal insulation is installed on top of the shielding heater. To determine heat loss, the radiator is disconnected from the heater chamber, plugs are installed and insulated. In stationary mode, the dependence of the heater power on the temperature of the heater chamber is measured, which determines the power of heat losses. The simplification of the installation has led not only to its reduction in price, but also to an increase in accuracy due to the reduction of heat losses and the simplicity of their definition.
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Mar’ina, Z. G., A. Yu Vereshchagin, and A. V. Novozhilova. "Study of the Influence of the Connection Mode of the STI Brand Aluminum Radiator on its Thermal Characteristics." ENERGETIKA. Proceedings of CIS higher education institutions and power engineering associations 65, no. 1 (February 2, 2022): 89–98. http://dx.doi.org/10.21122/1029-7448-2022-65-1-89-98.
Повний текст джерелаАнотація:
Aluminum radiators of various brands have become widespread on the market of heating equipment nowadays. It is possible to reduce the cost of manufacturing radiators by reducing the surface of the heat-emitting internal fins, while maintaining their appearance, and the heat transfer claimed by the manufacturer is being maintained high enough. Decree of the Government of the Russian Federation No 717 of June 17, 2017 introduced mandatory certification of all types of heating appliances. Deviations of the nominal thermal power of the section indicated in the device passport from the indicators established by the test results should not exceed the maximum permissible values (from –4 to +5 %). As a rule, no previous tests were carried out by the manufacturer. Thus, the study of the influence of the radiator connection mode with a reduced fin surface on its thermal characteristics is an urgent task. The article presents the results of the studies of a factory aluminum radiator with a reduced surface of STI Classic brand fins with a heat output of 1.92 kW under design conditions. The specified heat transfer of the device does not take into account its connection mode. The reduction of the inner and rear fins reduced its surface area by 28.8 %. As a result of the experiments carried out, it was found that the thermal power of the device is 22 % lower than the declared value when connected from top to bottom and 48 % lower when connected from bottom to top under design conditions. During the warmer period of the heating season, with a small temperature difference between the coolant and the indoor air, the average heat output of the radiator coincides with the declared value.
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Tuomas, Edvardas, and Saulius Neverbickas. "METHODOLOGY OF THE PRIMARY DATA RECONSTRUCTION OF SINGLE PIPE HEATING SYSTEMS/VIENVAMZDŽIŲ ŠILDYMO SISTEMŲ PIRMINIŲ DUOMENŲ NUSTATYMO METODIKA." JOURNAL OF CIVIL ENGINEERING AND MANAGEMENT 5, no. 5 (October 31, 1999): 318–22. http://dx.doi.org/10.3846/13921525.1999.10531482.
Повний текст джерелаАнотація:
The majority of dwellings in Lithuania are situated in blocks of flats. The dwellings were built after World War II and they are heated by single pipe central heating systems, connected to district heating. The dwellers are not quite satisfied with such a heating system and try to improve it, but do that in a wrong way, by increasing the surface of radiators. Such means lead to violation of thermal regime and comfort conditions for other dwellers. There exists sometimes the necessity of reconstructing premises and together—the heating system. During the reconstruction the primary heat fluxes from radiators should be known, but very often such data are lost and only the size of radiators (number of sections) are known. To reconstruct the required primary data for single pipe systems is complicated because the temperatures of inlet and outlet water for radiators are unknown. In this article the methodology is proposed how to perform the calculations leading to the required data. The aim of calculations is the establishment of heat fluxes from each radiator connected to the riser. Heat flux from radiator can be calculated according the formula (1) but the complex coefficient is unknown. It could be found from formulae (2) but some magnitudes are unknown. According to the proposed methodology the values of unknown magnitudes are taken approximately and calculations are performed with iterations. In such a way the flow rate of water in riser is established from formula (3), which is the same for each radiator (the property of single pipe system). From formulas (3) and (4) an equation is produced (5), and is used for calculations of unknown temperatures. The equation (6) is used for calculation of heat fluxes from radiators. To carry out the above-mentioned calculations without computer practically is impossible due to many cycles of iteration. The programme was prepared to make easy all these calculations. The scheme of algorithm of programme is given in Fig 1. An example of calculation is given in this article. Calculations were fulfilled by newly created programme. The riser chosen for calculation is shown in Fig 2. The results of calculation are given in Table 1. The table shows that according to the proposed methodology the programme based on it can be used for reconstruction of primary data of single pipe heating systems successfully.
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Qu, Sheng Guan, Li Kui Liu, Wen Long Li, Guang Hong Wang, and Xiao Qiang Li. "Honeycomb Radiator Cold Extrusion Forming Research." Advanced Materials Research 753-755 (August 2013): 149–54. http://dx.doi.org/10.4028/www.scientific.net/amr.753-755.149.
Повний текст джерелаАнотація:
Radiators plays a crucial role in thermal performance of LED Lamp, and the latest development of LED honeycomb radiator forming process has been discussed. Moreover, stress-strain state in the dies and blank flow condition with different die structures have been studied by DEFORM. Accordingly the feasibility of the optimization design also has been demonstrated. The results show that the substance flowing has a serious affect on the force to the die. And with an appropriate die structure, the uniformity of forming can be greatly improved and the force to the die can be reduced.
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Sun, Hongwei Zhu Huan, and Haorong Xu. "Numerical simulation of the effect of rib spacing on the heat transfer performance of micro pin-fin heat sink." Journal of Physics: Conference Series 2409, no. 1 (December 1, 2022): 012012. http://dx.doi.org/10.1088/1742-6596/2409/1/012012.
Повний текст джерелаАнотація:
Abstract This paper aims to deeply understand the influence of different columnar rib spacing on the comprehensive thermal hydraulic performance of miniature columnar rib radiator, and further explore the influence of flow and heat flow density Taking 10 miniature columnar rib radiator models as research objects, the single-phase heat transfer process of square miniature columnar rib radiator was studied. The experimental results show that for 10 kinds of miniature columnar rib radiators, the relationship between the maximum temperature difference at the bottom of the ribbed substrate will change with the change of temperature, with linear arrangement and cross arrangement.The maximum and minimum values are, respectively, when the longitudinal spacing is 0.75mm and 0.25 mm, and the maximum and minimum values are, respectively, when the transverse spacing is 0.5 mm and 1.25 mm.
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Uguz, Sinan, and Osman Ipek. "The Management of Indoor Thermal Comfort with Wireless Sensor Networks." Measurement and Control 50, no. 9-10 (November 2017): 206–13. http://dx.doi.org/10.1177/0020294017707228.
Повний текст джерелаАнотація:
In this study, real-time monitoring and control platform based on thermal comfort was developed to control space heating in living spaces. To calculate the thermal comfort level in a living space, environmental factors such as indoor air temperature, mean radiant temperature, air velocity, and humidity are needed. In order to obtain the environmental factors, sensor nodes based on wireless sensor networks were developed. According to the data obtained from the sensor nodes, the thermal comfort index was calculated, and radiators used for space heating were controlled via monitoring and control software based on PC. Furthermore, several experiments were performed between living spaces where real-time monitoring and control platform was installed and living spaces heated with conventional methods. The measurements were carried out in four rooms at the Faculty of Technology of Suleyman Demirel University in Turkey during the winter season. The heat transferred from room radiators by creating proper conditions that can change the thermal comfort index was compared in the experiments. During experimental measurements, it was observed that the heat transferred to the environment through the room radiators reduced significantly, especially with closed doors and windows.
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Ferrantelli, Andrea, Karl-Villem Võsa, and Jarek Kurnitski. "Optimization of Radiators, Underfloor and Ceiling Heater Towards the Definition of a Reference Ideal Heater for Energy Efficient Buildings." Applied Sciences 8, no. 12 (December 3, 2018): 2477. http://dx.doi.org/10.3390/app8122477.
Повний текст джерелаАнотація:
Heat emitters, as the primary devices used in space heating, cover a fundamental role in the energy efficient use of buildings. In the search for an optimized design, heating devices should be compared with a benchmark emitter with maximum heat emission efficiency. However, such an ideal heater still needs to be defined. In this paper we perform an analysis of heat transfer in a European reference room, considering surface effects of thermal radiation and computing the induced operative temperature (op.t.) both analytically and numerically. Our ideal heater is the one determining the highest op.t. By means of functional optimization, we analyse trends such as the variation of operative temperature with radiator panel dimensions, finding optimal configurations. To make our definitions as general as possible, we address panel radiators, convectors, underfloor (UFH) and ceiling heater. We obtain analytical formulas for the operative temperature induced by panel radiators and identify the 10-type as our ideal radiator, while the UFH provides the best performance overall. Regarding specifically UFH and ceiling heaters, we find optimal sizes providing maximum op.t. The analytical method and qualitative results reported in this paper can be generalized and adopted in most studies concerning the efficiency of different heat emitter types in building enclosures.
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Didmanidze, O. N., R. T. Khakimov, E. P. Parlyuk, and N. A. Bol’shakov. "Test Results of a Polymer Radiator of MTZ-80 Tractor Cooling System." Agricultural Machinery and Technologies 14, no. 1 (March 24, 2020): 55–60. http://dx.doi.org/10.22314/2073-7599-2020-14-1-55-60.
Повний текст джерелаАнотація:
Global car manufacturers wish to increase the number of manufactured products, reduce their cost and labor input. The choice of research areas, design and technological developments in radiator construction is an extremely important and urgent task, due to the mass production of radiators for tractors and automobiles on the one hand, and the favorable development prospects of these interrelated industries, on the other. (Research purpose) To substantiate theoretically and experimentally the use of a combined cooling system containing both aluminum and polymeric water radiators and similarly liquid-oil heat exchangers based on the four principles listed above on automobiles and tractors. (Materials and methods) The authors performed bench tests using a special wind tunnel to study the thermal and aerodynamic characteristics of a prototype tractor radiator with a polyurethane core. After reaching the steady-state operating mode of the installation, the experimental values were determined for the control and measuring instruments. (Results and discussion) The authors carried out measurements of all parameters of both coolants in series at each steady-state operating mode of the bench. They obtained the main indicators dependences (reduced heat transfer, aerodynamic and hydraulic drag) of the heat exchanger, close to the operating conditions of the vehicles. (Conclusions) A prototype MTZ-80 radiator with a polyurethane core has great prospects as a future alternative radiator. An increase by 10-15 percent in the radiator heat transfer is possible by using aluminum fi ns on the surface of the polyurethane plate. A 15-20 percent reduction in hydrodynamic resistance is achieved by increasing the diameter of the capillary throughput in a polyurethane plate and the number of plates themselves in the radiator cell.
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MASLYANITSYN, Alexander P., Elena V. MASLYANITSYNA, and Marina S. KRASNOVA. "MATHEMATICAL SIMULATION OF THE HEATING SYSTEM RADIATOR OF AS A CONTROL OBJECT." Urban construction and architecture 11, no. 3 (December 15, 2021): 38–43. http://dx.doi.org/10.17673/vestnik.2021.03.06.
Повний текст джерелаАнотація:
The problem of mathematical modeling of a heating system radiator as a control object is considered. The purpose of its development is to create a generalized mathematical model of thermal processes in a room heated by means of water radiators. A calculation scheme of heat transfer processes between the heat carrier of the radiator and the air of the room has been developed, on the basis of which the heat balance equations are writt en. This takes into account both steady and unsteady heat transfer processes between the coolant, radiator and room air. A block diagram of the mathematical model of a heating radiator has been developed. After the introduction of assumptions and transformation of the structural diagram of the nonlinear model, the structural diagram of the linear mathematical model of the heating radiator was obtained. On its basis, the transfer function of the heating radiator is derived, the output coordinate of which is the thermal power. The resulting transfer function can be used in a generalized mathematical model of a heated room. The analysis of the transfer function of the heating radiator is carried out and it is shown that its dynamics is determined not only by geometric parameters, but also by the fl ow rate of the heat carrier.
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Rymar, Tetiana, та Mariya Zayats. "Features of Replacement of the ТГМП-314 Boiler Heating Installation". NTU "KhPI" Bulletin: Power and heat engineering processes and equipment, № 3-4 (28 грудня 2022): 35–38. http://dx.doi.org/10.20998/2078-774x.2022.03.06.
Повний текст джерелаАнотація:
Thermal power stations play the main role not only in carrying the base load, but also in ensuring the coverage of peak and semi-peak loads of electricity consumption. Improving the operational maintenance of energy equipment gives a greater economic effect, since the costs of modernization of regenerative air heaters, which improve their density and thermal efficiency, are repaid in a short time. The efficiency and cost-effectiveness of the operation of regenerative air heaters was increased by the reconstruction of the heating installation. The results of the reconstruction of the design heaters of the TГМП-314 boilers with sections of sanitary-technical heaters КФСО -II and КФБО -II with replacement by sections of energy heaters (СО-110) are presented. The improved heating installation is installed in front of each regenerative air heater of the ТГМП-314 boiler and is made of two walls placed sequentially according to the air movement, in each of which 12 sections of reconstructed CO-110 heaters with a downward movement of the heating steam flow are installed. An important advantage of the proposed sequential installation of radiators is an increase in the uniformity of the temperature field in the box in front of the regenerative air heater due to two-stage air heating. Sequential installation of radiator walls increases the heat transfer coefficient approximately 1.6 times compared to parallel connection, which makes it possible to double the air speed in the radiators for the same number of sections. The possibility of formation of stagnant zones of sections of CO-110 heaters is excluded. In this case, it is recommended to reconstruct single-pass radiators with the installation of a pipe board and heating steam condensate removal chambers. The high efficiency of the improved heating installation made it possible to carry out all boiler ignitions with the possibility of supplying flue gases immediately through the RAH.
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Syed, Zaker A., and John R. Wagner. "Modeling and Control of a Multiple-Heat-Exchanger Thermal Management System for Conventional and Hybrid Electric Vehicles." Designs 7, no. 1 (February 1, 2023): 19. http://dx.doi.org/10.3390/designs7010019.
Повний текст джерелаАнотація:
The powertrain in combustion engine and electric vehicles requires a thermal management system to regulate the operating temperature of the under-hood components. The introduction of computer-controlled cooling system actuators (e.g., variable speed fans, pump, and valves) enables power savings over drive cycles. The radiator is typically sized for maximum heat rejection per environmental and vehicle thermal loading conditions. This paper explores the use of multiple radiators to adapt the cooling system operations to driving demands. A nonlinear multiple-input (i.e., fan array speed, pump, and outlet valve positions) thermal model is presented to predict system behavior. A stateflow controller has been designed and implemented to maintain the component temperature within a desired range (~80 °C). A series of experimental tests have been conducted to compare the proposed architecture’s performance against a single radiator design. A standard driving cycle featuring low (20 kW) and high (40 kW) heat loads was implemented in the laboratory for a vehicle starting from rest. The coolant temperature tracking, fan speeds, and fan power draw were studied over the representative operating cycle. The test results show a much faster warmup time (~10 min) and temperature tracking for the twin radiator experimental test as compared to the single radiator (~13 min). The net fan energy consumption was reduced by 4.6% with the twin radiator as opposed to the single-radiator configuration. Considering that engines usually operate at idle to medium loads, these findings can improve the powertrain’s overall performance.
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Swaid, H. "Transient nocturnal cooling of low thermal capacity radiators." Solar Energy 49, no. 6 (December 1992): 549–55. http://dx.doi.org/10.1016/0038-092x(92)90163-5.
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Menéndez-Díaz, Agustín, Celestino Ordóñez-Galán, José Benito Bouza-Rodríguez, and Javier Jesús Fernández-Calleja. "Thermal analysis of a stoneware panel covering radiators." Applied Energy 131 (October 2014): 248–56. http://dx.doi.org/10.1016/j.apenergy.2014.06.025.
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Glamazdin, P., P. Pasichnyk, and О. Priymak. "Possibilities of improving the design of sectional aluminium radiator." Ventilation, Illumination and Heat Gas Supply 41 (April 12, 2022): 24–31. http://dx.doi.org/10.32347/2409-2606.2022.41.24-31.
Повний текст джерелаАнотація:
The main trend in the development of district heating systems in recent years is a decrease in the temperature of heat carrier, based on the desire to include renewable energy sources in such systems. Despite the ever-increasing demands on the thermal envelope of buildings, lowering the temperature entails the need to increase the area of heating appliances. In turn, this leads to an increase in material consumption of heating systems, increasing their hydraulic resistance and design problems. In order to avoid or at least reduce these negative consequences of the struggle to increase the environmental friendliness and energy efficiency of district heating systems, it is necessary to intensify the heat dissipation of heating appliances. The existing designs of sectional aluminium radiators, which are the most promising for improving their thermal performance, have reached a certain limit in the design, to overcome which it is necessary to change the technology of manufacturing the heat dissipating element of the section. The article shows the reasons for the emergence of such a limit for the existing design of devices, formulates requirements for advanced designs and shows the way to achieve higher thermal performance. The article presents the results of calculations that confirm the presence of the detected limit of thermal performance of existing structures of sectional aluminium radiators. Based on the analysis of existing designs and the identified limits of their further development, a new design of aluminium sectional heating device is proposed, which allows to bypass and overcome the limitations that are characteristic of existing ones. The results of calculations showing the possibilities of intensification of heat transfer of a sectional aluminium device are given. At the same heat output, the dimensions of the proposed radiator will be about thirty percent smaller than the size of existing appliances. The article presents the results of tests of prototypes of sectional radiators of the new design, manufactured using new technology. Devices consisting of seven sections of three sizes in height were investigated: 293 mm, 596 mm, 1097 mm. The results of the study confirmed previous theoretical developments. The tests were conducted in a laboratory certified according to European Union standards at the Institute of Heating and Sanitary Engineering in Radom (Poland).
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Gutierrez, Mario, Antonio Ramos, Josefina Gutierrez, Arturo Vera, and Lorenzo Leija. "Nonuniform Bessel-Based Radiation Distributions on A Spherically Curved Boundary for Modeling the Acoustic Field of Focused Ultrasound Transducers." Applied Sciences 9, no. 5 (March 4, 2019): 911. http://dx.doi.org/10.3390/app9050911.
Повний текст джерелаАнотація:
Therapeutic focused ultrasound is a technique that can be used with different intensities depending on the application. For instance, low intensities are required in nonthermal therapies, such as drug delivering, gene therapy, etc.; high intensity ultrasound is used for either thermal therapy or instantaneous tissue destruction, for example, in oncologic therapy with hyperthermia and tumor ablation. When an adequate therapy planning is desired, the acoustic field models of curve radiators should be improved in terms of simplicity and congruence at the prefocal zone. Traditional ideal models using uniform vibration distributions usually do not produce adequate results for clamped unbacked curved radiators. In this paper, it is proposed the use of a Bessel-based nonuniform radiation distribution at the surface of a curved radiator to model the field produced by real focused transducers. This proposal is based on the observed complex vibration of curved transducers modified by Lamb waves, which have a non-negligible effect in the acoustic field. The use of Bessel-based functions to approximate the measured vibration instead of using plain measurements simplifies the rationale and expands the applicability of this modeling approach, for example, when the determination of the effects of ultrasound in tissues is required.
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Bhattad, Atul, Vinay Atgur, Boggarapu Nageswar Rao, N. R. Banapurmath, T. M. Yunus Khan, Chandramouli Vadlamudi, Sanjay Krishnappa, A. M. Sajjan, R. Prasanna Shankara, and N. H. Ayachit. "Review on Mono and Hybrid Nanofluids: Preparation, Properties, Investigation, and Applications in IC Engines and Heat Transfer." Energies 16, no. 7 (March 31, 2023): 3189. http://dx.doi.org/10.3390/en16073189.
Повний текст джерелаАнотація:
Nano fluids are widely used today for various energy-related applications such as coolants, refrigerants, and fuel additives. New coolants and design modifications are being explored due to renewed interest in improving the working fluid properties of heat exchangers. Several studies have investigated nanofluids to enhance radiator and heat exchanger performance. A new class of coolants includes single, binary, and tertiary nanoparticle-based hybrid nano-coolants using ethylene glycol/deionized water combinations as base fluids infused with different nanoparticles. This review article focuses on the hydrothermal behavior of heat exchangers (radiators for engine applications) with mono/hybrid nanofluids. The first part of the review focuses on the preparation of hybrid nanofluids, highlighting the working fluid properties such as density, viscosity, specific heat, and thermal conductivity. The second part discusses innovative methodologies adopted for accomplishing higher heat transfer rates with relatively low-pressure drop and pump work. The third part discusses the applications of mono and hybrid nanofluids in engine radiators and fuel additives in diesel and biodiesel blends. The last part is devoted to a summary of the research and future directions using mono and hybrid nanofluids for various cooling applications.
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Parlyuk, E. P., and A. V. Kurilenko. "Methodology For Calculating Automotive Oil Radiator." Agricultural Machinery and Technologies 16, no. 2 (June 29, 2022): 37–42. http://dx.doi.org/10.22314/2073-7599-2022-16-2-37-42.
Повний текст джерелаАнотація:
The paper highlights the relevance of the problem of determining the amount of heat supplied by an internal combustion engine to a liquid cooling system when creating typical series of unified heat exchangers for tractor and combine engines (power units). A properly designed cooling system further guarantees the maintenance of the optimal thermal mode for the engine operation. A methodology for calculating the coolant characteristics of the cooling system was proposed in order to prevent possible problems related to increased parts wear, early loss of oil lubricating properties, the engine (individual units) and rubbing parts overheating, a decrease in engine power and a deterioration in the quality of the fuel-air mixture entering the cylinders.Research purpose To develop a methodology for calculating the amount of heat to be dissipated by the oil radiators of a liquid cooling system (lubrication system) being exposed to various load and engine speed modes.Materials and methods It was proposed to determine the amount of heat to be dissipated by the liquid-oil heat exchanger of the engine lube oil cooling system.Results and discussion The calculation method for oil radiators presents the calculation of the heat obtained by oil during the operation of 37-110 kilowatts automotive engines. The heat-dissipating ability of the oil surface is determined. A parameter taking into account the oil radiator heat flow is identified. The graphs of the oil surface and heat flux dependence on the engine power are presented.Conclusions The method for calculating the temperature and dynamic characteristics of the automotive engine cooling system has been developed. It makes it possible to carry out research on the radiator thermal and technical characteristics in various operating modes of machines and coolants of systems, various heat exchanger structural materials (metal, polymer), with an error of 1.5-8.0 percent.
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Selvadurai, Shanmugasundaram, Amal Chandran, David Valentini, and Bret Lamprecht. "Passive Thermal Control Design Methods, Analysis, Comparison, and Evaluation for Micro and Nanosatellites Carrying Infrared Imager." Applied Sciences 12, no. 6 (March 10, 2022): 2858. http://dx.doi.org/10.3390/app12062858.
Повний текст джерелаАнотація:
Advancements in satellite technologies are increasing the power density of electronics and payloads. When the power consumption increases within a limited volume, waste heat generation also increases and this necessitates a proper and efficient thermal management system. Mostly, micro and nanosatellites use passive thermal control methods because of the low cost, no additional power requirement, ease of implementation, and better thermal performance. Passive methods lack the ability to meet certain thermal requirements on larger and smaller satellite platforms. This work numerically studies the performance of some of the passive thermal control techniques such as thermal straps, surface coatings, multi-layer insulation (MLI), and radiators for a 6U small satellite configuration carrying a mid-wave infrared (MWIR) payload whose temperature needs to be cooled down to 100K. Infrared (IR) imagers require low temperature, and the level of cooling is entirely dependent on the infrared wavelengths. These instruments are used for various applications including Earth observations, defence, and imaging at IR wavelengths. To achieve these low temperatures on such instruments, a micro-cryocooler is considered in this study. Most of the higher heat dissipating elements in the satellite are mounted to a heat exchanger plate, which is thermally coupled to an external radiator using thermal straps and heat pipes. The effects of the radiator size, orbital inclinations, space environments, satellite attitude with respect to the sun, and surface coatings are discussed elaborately for a 6U satellite configuration.
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Ivankov, V. F., А. V. Basova, and І. V. Khimjk. "REDUCTION OF LOCAL HEATING IN TANKS OF POWERFUL TRANSFORMERS BY HEAT-REMOVING LOCAL RADIATORS WITH RIBBED." Praci Institutu elektrodinamiki Nacionalanoi akademii nauk Ukraini 2021, no. 58 (May 19, 2021): 82–89. http://dx.doi.org/10.15407/publishing2021.58.082.
Повний текст джерелаАнотація:
The main approaches, the results of numerical modeling, and examples of the practical application of heat-dissipating radiators made of aluminum, with a flat base, and with ribbing to reduce local heating in ferromagnetic covers and walls of transformer tanks, which arise in cases of concentration of magnetic fluxes from multi-ampere taps or magnetic shunts are presented. The case of thermal coupling of a non-magnetic flange of a yoke beam with a flat base of a radiator (copper plate) is considered, which shows the possibility of reducing local heating of the beam using conductive heat transfer between the shelf and the plate and convection heat transfer from their surfaces to cooling oil. References 4, figures 7.
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Marchesi, Renzo, Fabio Rinaldi, Claudio Tarini, Fausto Arpino, Gino Cortellessa, Marco Dell’Isola, and Giorgio Ficco. "Experimental analysis of radiators’ thermal output for heat accounting." Thermal Science 23, no. 2 Part B (2019): 989–1002. http://dx.doi.org/10.2298/tsci170301168m.
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Komatubara, T. "A Study for Improving Thermal Effectiveness in Automotive Radiators." JSAE Review 16, no. 1 (January 1995): 111. http://dx.doi.org/10.1016/0389-4304(95)94860-p.
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Mao, Shaolin, Changrui Cheng, Xianchang Li, and Efstathios E. Michaelides. "Thermal/structural analysis of radiators for heavy-duty trucks." Applied Thermal Engineering 30, no. 11-12 (August 2010): 1438–46. http://dx.doi.org/10.1016/j.applthermaleng.2010.03.003.
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Liu, Jie, Shuang Xi Zhang, and Yu Feng He. "Investigation on Double-Tube Copper-Aluminum Column-Wing Type Radiators." Advanced Materials Research 243-249 (May 2011): 4883–86. http://dx.doi.org/10.4028/www.scientific.net/amr.243-249.4883.
Повний текст джерелаАнотація:
The calculation formulas are provided for calculating the heat release and metal thermal intensity of double-tube copper-aluminum Column-wing type radiator, and the reliability of the theoretical calculation is verified. The metal thermal intensity is taken as an optimization index, with theoretical calculations for different sorts of tube diameters and overall dimensions, obtains the optimalizing dimension of the radiator.
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Zhang, Jiaming, Fuwu Yan, Changqing Du, Wenhao Li, Hongzhang Fang, and Jun Shen. "Model-Based Performance Optimization of Thermal Management System of Proton Exchange Membrane Fuel Cell." Energies 16, no. 9 (May 8, 2023): 3952. http://dx.doi.org/10.3390/en16093952.
Повний текст джерелаАнотація:
As a promising new power source, the proton exchange membrane fuel cell (PEMFC) has attracted extensive attention. The PEMFC engine produces a large amount of waste heat during operation. The excessive temperature will reduce the efficiency and lifespan of PEMFC engine and even cause irreversible damage if not taken away in time. The thermal management system of the PEMFC plays a critical role in efficiency optimization, longevity and operational safety. To solve the problem of high heat production in the operation of the PEMFC, two approaches are proposed to improve the heat dissipation performance of the radiators in thermal management systems. Three kinds of nanofluids with excellent electrical and thermal conductivity–Al2O3, SiO2 and ZnO– are employed as the cooling medium. The radiator parameters are optimized to improve the heat transfer capability. A typical 1D thermal management system and an isotropic 3D porous medium model replacing the wavy fin are constructed to reveal the effects of the nanofluid and the parameters of the radiator performance and the thermal management system. The results show that all three kinds of nanofluids can effectively improve the heat transfer capacity of the coolant, among which the comprehensive performance of the Al2O3 nanofluid is best. When the mass flow rate is 0.04 kg/s and the concentration is 0.5 vol%, the amount of heat transfer of the Al2O3 nanofluid increases by 12.7% when compared with pure water. Under the same conditions, it can reduce the frontal area of the radiator by 12%. For the radiator, appropriate reduction of the fin pitch and wavy length and increase of wave amplitude can effectively improve the spread of heat. The use of fin parameters with higher heat dissipation power results in lower coolant temperatures at the inlet and outlet of the stack. The performance of the radiator is predicted by the two model-based approaches described above which provide a reliable theoretical basis for the optimization of the thermal management system and the matching of the components.
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Adnan та Waqas Ashraf. "Numerical thermal featuring in γAl2O3-C2H6O2 nanofluid under the influence of thermal radiation and convective heat condition by inducing novel effects of effective Prandtl number model (EPNM)". Advances in Mechanical Engineering 14, № 6 (червень 2022): 168781322211065. http://dx.doi.org/10.1177/16878132221106577.
Повний текст джерелаАнотація:
The investigation of thermal transport in the nanofluid attained much interest of the researchers due to their extensive applications in automobile, mechanical engineering, radiators, aerodynamics, and many other industries. Therefore, a nanofluid model is developed for γAl2O3-C2H6O2 by incorporating the novel effects of Effective Prandtl Number Model (EPNM), thermal radiations, and convective heat condition. The model discussed numerically and furnished the results against the governing flow quantities. It is examined that the nanofluid velocity alters significantly due to combined convection and stretching parameter. Induction of thermal radiation in the model significantly contributed in the temperature of nanofluids and high temperature is observed by strengthen thermal radiation (Rd) parameter. Further, convection from the surface (convective heat condition) provided extra energy to the fluid particles which boosts the temperature of γAl2O3-C2H6O2. The comparison of nanofluid (γAl2O3-C2H6O2) temperature with base fluid (C2H6O2) revealed that γAl2O3-C2H6O2 has high temperature and would be fruitful for future industrial applications. Moreover, the study is validated with previously reported literature and found reliability of the study.
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Ovcharenko, Sergei, Oleg Balagin, Dmitrii Balagin, and Viktor Vedruchenko. "Integrated system of non-contact thermal control of the units of self-contained locomotives." MATEC Web of Conferences 239 (2018): 01002. http://dx.doi.org/10.1051/matecconf/201823901002.
Повний текст джерелаАнотація:
The stages of implementation of the integrated system of non-contact thermal control of the main units and systems of self-contained locomotives are considered. The developed techniques for assessing the technical state of sections of radiators, electrical machines, and high-pressure fuel equipment of self-contained locomotives using the thermal imaging control method are presented.
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Dobrzański, L., and J. Piotrowski. "Micromachined silicon thermopile and thermal radiators using porous silicon technology." IEE Proceedings - Optoelectronics 145, no. 5 (October 1, 1998): 307–11. http://dx.doi.org/10.1049/ip-opt:19982301.
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Yedikardeş, Yıldıray, and İsmail Teke. "Effect of louvres on the thermal efficiency of panel radiators." International Communications in Heat and Mass Transfer 88 (November 2017): 160–70. http://dx.doi.org/10.1016/j.icheatmasstransfer.2017.07.017.
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Robinson, A. J. "A thermal model for energy loss through walls behind radiators." Energy and Buildings 127 (September 2016): 370–81. http://dx.doi.org/10.1016/j.enbuild.2016.05.086.
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