ABSTRACT

The thermal performance of a novel solar air heater was experimentally studied in this paper. For this aim, a new solar air collector was designed using copper wool on its absorber plate to be a selective surface. Hence, the area of absorber plate was enhanced to absorb much amount of heat energy. The experimental study was conducted for both cases (presence and absence of copper wool on the absorber plate) to determine the effect of copper wool on the thermal efficiency of the collector. The mass flow rate values of the study were 0.035 and 0.044 kg/s. The results pointed out that fluid temperature at outlet of collector with copper wool was increased by about 8 to14%. Therefore, these collectors may be suitable for space heating and drying of food applications. However, copper wool caused more pressure loss through the collector by 40% compared to simple case of collector. The thermal efficiency of the collectors was obtained as 34 to 83% depending on experimental variable parameters. Similarly, effective efficiency of collectors was computed to be 24 to 70%. It is found that efficiency of the collector was improved when using copper wool on the absorber plate as well as increasing mass flow rate of air.

摘要

本文通过实验研究了新型太阳能空气加热器的热性能。为此，设计了一种新的太阳能集热器，在其吸收板上使用铜棉作为选择性表面。因此，增加了吸收板的面积以吸收大量的热能。在这两种情况下（吸收板上是否存在铜棉）进行了实验研究，以确定铜棉对集热器热效率的影响。研究的质量流率值为0.035和0.044 kg / s。结果表明，铜棉集热器出口处的流体温度提高了约8％至14％。因此，这些收集器可能适用于空间加热和食品干燥应用。然而，与简单的收集器相比，铜棉通过收集器造成的压力损失增加了40％。根据实验变量参数，收集器的热效率为34％至83％。同样，收集器的有效效率经计算为24％至70％。已经发现，当在吸收板上使用铜棉以及增加空气的质量流量时，收集器的效率得以提高。