Vol 7, No 7 (2016) > Mechanical Engineering >

The Behavior of Lewis Number in Finned Tube Cooling Coils under Highly Moist Inlet Air Conditions

Teerachai Howongsakun, Somnuk Theerakulpisut, Purimpat Sujumnongtokul, Pattayagorn Palasan

 

Abstract: The objective of this research was to study the effects of highly moist inlet air conditions such as temperature, relative
humidity, and frontal air velocity on the value of the Lewis number (Le) in the cooling and dehumidifying process of air. A finned tube cooling coil was tested
under ranges of temperature, relative humidity and frontal velocity. It was
found that the Lewis number (Le) varied within the range of 0.92-1.62 and that the increase in inlet air relative humidity tends to
decrease the Lewis number (Le). Based on the
experimental, a correlation for predicting the Lewis number (Le) was also established in this article. The
correlation has the mean absolute error (MAE) of 3.04% and covers 98.07% of the data where a discrepancy within ± 10%.
Keywords: Cooling coils; Dehumidifying process; Lewis number; Moist air

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