畢業(yè)設計外文翻譯----冷卻系統(tǒng)利用流體吸熱交換器-在線瀏覽
2025-07-30 23:20本頁面
【正文】 nce (expressed in terms of a system coefficient of performance, COP). The influence of liquidsuction heat exchanger size over a range of operating conditions (evaporating and condensing) is illustrated and quantified using a number of alternative refrigerants. Refrigerants included in the present analysis are R507A, R404A, R600, R290, R134a, R407C, R410A, R12, R22, R32, and R717. This paper extends the results presented in previous studies in that it considers neW refrigerants, it specifically considers the effects of the pressure drops,and it presents general relations for estimating the effect of liquidsuction heat exchangers for any refrigerant. Heat Exchanger Effectiveness The ability of a liquidsuction heat exchanger to transfer energy from the Warm liquid to the cool vapor at steadystate conditions is dependent on the size and configuration of the heat transfer device. The liquidsuction heat exchanger performance, expressed in terms of an effectiveness, is a parameter in the analysis. The effectiveness of the liquidsuction heat exchanger is defined in equation (1): Where the numeric subscripted temperature (T) values correspond to locations depicted in Figure 1. The effectiveness is the ratio of the actual to maximum possible heat transfer rates. It is related to the surface area of the heat exchanger. A zero surface area represents a system Without a liquidsuction heat exchanger Whereas a system having an infinite heat exchanger area corresponds to an effectiveness of unity. The liquidsuction heat exchanger effects the performance of a refrigeration system by in 4 fluencing both the high and loW pressure sides of a system. Figure 2 shoWs the key state points for a vapor pression cycle utilizing an idealized liquidsuction heat exchanger on a pressureenthalpy diagram. The enthalpy of the refrigerant leaving the condenser (state 3) is decreased prior to entering the expansion device (state 4) by rejecting energy to the vapor refrigerant leaving the evaporator (state 1) prior to entering the pressor (state 2). Pressure losses are not shoWn.
畢業(yè)設計相關(guān)推薦
鄂ICP備17016276號-1