Characteristics Study On Pulsating Heat Pipe Used In Energy Recovery

Pulsating heat pipe is associated with microelectronics technology and developed newand efficient heat transfer original，it has a simple structure, low cost, and good heat transferperformance.Meanwhile, the pulsating heat pipe is also a set of sensible heat and phasechange heat transfer in one multidisciplinary complex two-phase flow system，although manyscholars have studied，however, the mechanism is not very mature research. This studywas based on previous studies, the use of mixed refrigerants phase transition temperaturechanges with the mixing ratio of components and non-azeotropic refrigerant temperature equi-librium state slip characteristics, combined with the pulsating heat pipe heat transfer compon-ents, the characteristics of pulsating heat pipe mixtures were filling the physical transmissioncharacteristics,heat transfer characteristics and heat transfer performance of the study. Simula-ted summer conditions in the experimental stage, it has been hot and cold air conditioningsystem heat recovery properties.In theory, this paper first filling of the pulsating heat pipe filling working fluid (singlerefrigerat and mixed refrigerant) and thermal parameters programmed for theoreticalcalculations, from the working fluid pressure, density, surface tension, latent heat ofvaporization, thermal conductivity, heat and other thermal parameters to consider, accordingto the pulsating heat pipe of the different actual operating temperature range, select theappropriate pulsating heat pipe work of the mixture working fluid; and from the saturatedvapor pressure, saturation pressure with saturation temperature change rate of the refrigerantcriteria several other angles to predict the filling refrigerant heat transfer performance,compared with the experimental results and getted the mixture refrigerant heat to be superiorto a single result in heat pipe transfer performance.In the experiment, it set up a pulsating heat pipe heat recovery bench, this test mainly co-mposed of pulsating heat pipe heat exchanger, hot air and cold generation device, pulsating h-eat pipe heat exchanger angle change, power distribution box, test and data acquisition syste-m.Pulsating heat pipe first is filling of the superior heat transfer characteristics mixtures. Takeinto account the pulsating heat pipe is used air conditioning system for energy recovery betw-een hot and cold air,in view of such a heat exchanger working conditions are harsh, so first dosome research in the minimum start doing of pulsating heat pipe heat recovery，the resultsshow that wind speed in the face of1.5-2.5m/s, the summer temperature is the start condition2.5℃. Secondly,do some research in different refrigerant, the refrigerant corresponding toeach of the four angles, different head-wind experiment, the method is to keep the condensersection inlet temperature constant, and gradually increase the evaporator temperature,analysisof various factors on the heat recovery efficiency, the results show that the hot sectiontemperature on heat recovery efficiency of greater than head-wind effects. Moreover, someexperimental correlations were established to predict the heat flux of pulsating heat pipe energy recovery at normal states. Taken together，pulsating heat pipe air conditioning systemin hot and cold recovery energy showed a greater superiority and value.In addition, through the pulsating heat pipe hot section and cold section, adiabatic sectio-n arranged corresponding thermocouple and test temperature, never a visualpoint of view of t-he pulsating flow inside the heat pipe flow pattern. Experimental results show that,comparedpared with a single refrigerant, the pulsating heat pipe use the mixture refrigerant,the hot andcold heat recovery unit’efficiency is higher.