Composite-Channel Roll-Bond Evaporator Used in a Direct Expansion Solar Assisted Heat Pump System
Solar thermal and heat pump are two most promising renewable energy technologies for domestic hot water(DHW),and solar radiation has been considered by many researchers as an assistant heat source to improve the performance of a heat pump water heater.The so-called DX-SAHP(direct expansion solar assistant heat pump)water heater is a kind of composite system that combines solar thermal and heat pump together to further reduce energy consuming for DHW.In a DX-SAHP system,the solar collector and the evaporator are combined into one unit,which is also the most important component of the system.Since conventional solar collectors or evaporators could not perform well in both solar radiation absorbing and convectional heat exchanging,in this study,a composite channel roll-bond panel surface treated with black chromium plating was designed and used as solar collector/evaporator in a DX-SAHP water heater.A roll-bond panel is a kind of heat exchanger made of two Aluminum sheets rolled together.The refrigerant flow channel is printed onto the Al sheets with graphite before the rolling process and created by pressuring after.Surface treated with black chromium,the roll-bond panel shows good performance in both solar absorptivity and convectional heat exchanging.Considering that the rollbond panel is cheap,efficient,flexible and easy to design and fabricate,it is a good choice to be used as the solar collector/evaporator in a DX-SAHP system.In this investigation,flow channel networks of the roll-bond panels were designed and optimized to improve refrigerant flow distribution and heat transfer performance.Numerical and experimental studies of the DX-SAHP water heater using roll-bond evaporators with different types of channel patterns were carried out.Results showed that,roll-bond panels with composite channel networks performed much better than that with a conventional S-shaped channel pattern.
DX-SAHP Water Heater Roll-bond Evaporator Composite Channel COP
X.L.SUN X.L.SUN J.Y.WU R.Z.WANG
Institute of Refrigeration and Cryogenics,Shanghai Jiao Tong University,Shanghai,China,CA Institute of Refrigeration and Cryogenics,Shanghai Jiao Tong University,Shanghai,China,CA;Key Labora
国际会议
桂林
英文
1-13
2013-07-16（万方平台首次上网日期，不代表论文的发表时间）