Experimental Investigations On The Heat Transfer And Flow Characteristic Of The Indirect Evaporative Cooler

Nowadays, the issue of energy is widely concerned by more and more people. To meet the need of energy-conservation and environmental protection, technology of evaporative cooling is deeply investigated and broadly applied. The plate type indirect evaporative cooler has great value in the field of energy recovery, pre-cooling of fresh air, and the liquid desiccant air conditioning system for its high heat transfer coefficient, compact structure, and small flow resistance.Wide experimental investigation is conducted on the experimental setup. The effect of some parameters on the heat transfer performance of the indirect evaporative cooler is discussed. The results show that a higher inlet temperature of the primary air stream, a higher inlet velocity of the secondary air stream, a higher inlet wet bulb temperature of the secondary air stream, and a lower inlet velocity of the primary air stream yield a higher effectiveness of the indirect evaporative cooler. Experimental research on the friction factor is also carried out. The results indicate that the measured f Revalues are higher than classical theory prediction and increased with the Reynolds number. The marking point is about 1700 when the flow transforms from laminar to transition flow, is about 2100 when it transformed to turbulent flow. A comparative study between the experimental results and the theoretical values shows the actual value ofσ/Leunder the spray volume of 37L/h is about 0.2. The results obtained in the paper can be helpful on the design of the heat exchanger and also can help you to recognize the mechanisms of the heat and mass transfer processes in the indirect evaporative cooler.