.tfe / Nmp Absorption Heat Pump Simulation And Experimental Study

The study of the alternative of tradition working pairs has been made for years, but the investigation about TFE/NMP is seldom reported. This work deals with the simulation and experimental research of a TFE/NMP absorption heat pump system. The effect of main operation parameters (evaporation temperature, condensation temperature, cycle ratio and the concentration of weak solutions) on the coefficient of performance (cop) was studied. The optimal parameters are obtained. With the analysis of calculation results and experimental data, it is proved that the introduction of supercooler, reboiler, recycle condenser and forced spray distribution into the system can effectively increase the coph as much as 15% from 1.33 to 1.53.In addition, with focus on the phenomenon of unequal distribution, the experiment about the distributor of evaporator is made with water and ethanol as working liquids. But the experimental result shows that the unequal distribution can be resolved by the improvement of the distributor. So the paper investigates the heat transfer characteristics of falling film evaporation on horizontal microfinned tubes with forced spray cycle. The result shows that the total heat transfer coefficients of enhanced tubes are 1.2-1.5times as high as those of smooth tubes. The relation about heat transfer coefficients on evaporation side and spray amount and the flow ratio is studied. The experimental result shows that the heat transfer coefficients (he) on evaporation side of enhanced tubes are 3-8 times as high as those of smooth tubes. The heat transfer coefficients (he) are increased with the flow ratio inside tubes, but they almost have nothing to do with the spray amount within the scope of test. Six dimensionless correlations of h* are obtained from experimental data. The percentage deviation between the calculation and experimental value is less than 30%.