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ugg italia Forced air-cooled condenser heat transf |
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Forced air-cooled condenser heat transfer analysis
Plain film is about 20% higher,[link widoczny dla zalogowanych], flat window, open the window radial fin higher than 80% of plain films, while the corrugated window, open the window a hundred blade plain films will have higher than about 120%. Because the data difference between the larger variety of materials, for the use of wavy fin and tube fin cluster, the air side heat transfer coefficient is currently no simple and accurate calculation of relationships, so the selection and design on the fin is still in the research and exploration phase. The practice of a number of manufacturers and companies that use wavy fin and fin, the air side heat transfer coefficient is generally higher than 20%, respectively, plain fin and more than 60% If so, those calculations and corrugated fin fin pipe cluster when the air side heat transfer coefficient can be calculated initially flat film sets,[link widoczny dla zalogowanych], and then multiplied by 1.2 and 1.6, can be calculated in the fin tube finned tube clusters and clusters of the air gap side heat transfer coefficient of the approximation. The main function of the hydrophilic membrane treatment mentioned above, is to enhance the film thinning through the landscape, there is information indicating that the hydrophilic film evaporator using air pressure after the loss can be reduced 4050%, which can increase the cooling capacity of 2 - 3%. Drag of fins of different types are different, in certain circumstances, fans, and sometimes high heat transfer coefficient 'of the fin are always effective and is not necessarily good, because the heat transfer coefficient increased with air flow to reduce the effect of mutual offset. This forced ventilation in the design and calculation of stroke volume of the condenser by the condenser heat transfer decision,[link widoczny dla zalogowanych], according to the literature [6] calculations. Meanwhile, the computer program does not take into account type and arrangement of fin spacing and other factors on the impact of wind. 4.2 brass condenser tubes are triangular type with internal thread groove, deep groove, and Taiwan-based channel, our data show that compared with the light pipe,[link widoczny dla zalogowanych], the heat transfer coefficients are larger 50-150%, while the refrigerant flow pressure loss to a large 10,120 percent. According to the literature data [4] [5], internal thread copper tube to enhance the heat transfer coefficients values are: triangular groove: 1.7; Goushen: 2.1; platform type trench: 2.7. Pressure loss coefficient values are: (1) evaporates, the triangular channel: 1.13; deep groove: 1.55; platform type trench: 1.3; (2) condensation, triangular groove: 1.33; deep groove : 2.2; platform type trench: 1.66. In fact, whether a variety of fin types and compared with plain film, or various types of internal thread pipe and bare compared to both the pressure loss coefficient of heat transfer coefficient is compared with the light pipe, the ratio is not simple was set to the value of relationships, but in the heat transfer within the air conditioner, the changes are not large, and is considered value will greatly facilitate the handling of the issue, a relatively simple way is to take an average within a certain range value. In the air conditioner heat exchanger calculations,[link widoczny dla zalogowanych], to dealing with air, refrigerant state parameters calculated on the calculation of these parameters can be taken [6] [7] [8] in the formula provided for. 5 Conclusion: Forced air cooling condenser is important to run air conditioning system heat exchanger. 1) can improve the heat transfer coefficient, increase the heat transfer area and increase the heat transfer temperature difference of three ways to increase the heat transfer; 2) The forced air-cooled condenser on the heat transfer analysis, heat transfer efficiency by choosing fin, can increase the heat transfer coefficient. 3) With the small diameter of the heat exchanger, the refrigerant flow resistance on the side can not be ignored, so the calculation of the air conditioner should be aluminum type, the inner surface of copper tube type, the role of flow resistance and other factors into account . Through proper design the structure of the condenser, select the appropriate fin to maximize the heat transfer performance can be improved refrigeration systems, especially air-conditioning system functioning economy and reliability. References 1. Sun Wenchen. Air-cooled heat exchanger heat transfer enhancement of the experimental analysis. Guangdong Shunde: United States air-conditioner Manufacturing Co., Ltd. 2. Yang Shiming. Heat transfer. Beijing: People's Education Press, 19803. Zhouqi Jin and so on. Strip fin heat exchanger performance. Shanghai Mechanical College. 19874. Liu Zhigang, Liu Xian set, Zhao Guanchun. Calculation of physical properties of the working fluid preparation and application procedures. Beijing: Science Press, 19925. Zhou Guangliang. Room empty words debugging and cooling capacity calculation methods. Refrigeration, 19956. Wu industry is. Small refrigeration device design guidelines. Beijing: Mechanical Industry Press, 19987. Zhou Guangliang. Computer room air conditioner cooling system Check Calculation (AComputerProgramforCheckCalculationofRoomAir.. Condi .. tioner). Guangdong: --- Air Conditioner Co., Ltd. Mitsubishi Heavy Industries, Jinling 8. Zhigang, Yu Bingfeng. Domestic refrigeration and air conditioning Heat Exchanger Research. Xi'an: Xi'an Jiaotong University, one of a 9
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