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Effect on Stratification due to Diffuser Shape in a Thermal Storage Tank  

Lee Young-Soo (Unutilized Energy Research Center, Korea Institute of Energy Research(KIER))
Lee Sang-Nam (Unutilized Energy Research Center, Korea Institute of Energy Research(KIER))
Kim Jong-Ryul (Unutilized Energy Research Center, Korea Institute of Energy Research(KIER))
Publication Information
Korean Journal of Air-Conditioning and Refrigeration Engineering / v.17, no.11, 2005 , pp. 990-997 More about this Journal
Abstract
The stratified effect was investigated with three different types of diffuser shape in a thermal storage tank with variation of diffuser diameter, velocity, Froude number etc. Its effect was estimated by the degree of stratification. No matter of diffuser diameter and shape, the degree of stratification was the best as the Froude number gets closer to 1. In the case of a curved diffuser, when its diameter is a quarter of tank diameter and ejection velocity in a diffuser is approximately 0.2 m/s, the Froude number was almost 1. In the case of a flatted diffuser, when ejection velocity was 0.05 m/s, the Froude number was 1.5. Both cases which Froude number were nearer 1, showed the good degree of stratification.
Keywords
Thermal storage tank; Diffuser; Degree of stratifcation;
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