Direct expansion solar assisted heat pump using novel fin-tube collector/evaporator

doi:10.11949/j.issn.0438-1157.20161394

Abstract

Abstract:

A novel fin-tube collector/evaporator was used in a direct expansion solar assisted heat pump(DX-SAHP)water heater.The test rig was tested and several optimization schemes were proposed.The temperature of the collector is usually lower than ambient temperature,which means the collector can absorb heat not only from the solar radiation but also from the environment,so the collector efficiency is high.This novel collector has a bigger heat exchanger area compared with the same-sized roll-board collector.Experimental results show that the average COP of the DX-SAHP water heater can reach 5.37 when the temperature of 150-liter water is increased from 20℃ to 50℃ on sunny days in autumn.And the average COP can reach 3.43 even if on a rainy day with 18.6℃ average ambient temperature.A numerical model of the test rig was established and some optimization schemes for the collector were proposed.The computer simulation results show that the average COP of the DX-SAHP system can reach 6 when the temperature of 150L water is increased from 20℃ to 50℃ on sunny days after the optimization.

Key words: solar energy, heat pump, collector/evaporator, coefficient of performance, computer simulation, optimization

摘要：

将一种新型肋片式集热器/蒸发器应用于直膨式太阳能热泵热水器，对其进行实验研究，并提出一系列优化方案。由于集热器表面温度通常低于环境温度，集热器除了从太阳辐射中吸收热能，还能从空气中吸收部分热能，集热效率较高。相同外形尺寸条件下，新型集热器较吹胀板集热器有更大的换热面积。实验结果表明，在天气晴朗的秋季，将150L水从20℃左右加热至50℃，热泵的平均供热性能系数（COP）能达到5.37，即使在环境温度为18.6℃的小雨天气，系统平均COP依旧能够达到3.43。对实验样机建立仿真模型，并针对新型集热器提出一系列优化方案，计算机模拟结果表明，经过优化，在晴朗天气将150L水从20℃加热至50℃，系统的平均COP可达到6。

关键词: 太阳能, 热泵, 集热器/蒸发器, 性能系数, 计算机模拟, 优化

CLC Number:

TK519

JIANG Cheng, DAI Yanjun. Direct expansion solar assisted heat pump using novel fin-tube collector/evaporator[J]. CIESC Journal, 2016, 67(S2): 318-325.

蒋澄阳, 代彦军. 基于肋片式集热板的直膨式太阳能热泵[J]. 化工学报, 2016, 67(S2): 318-325.

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