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source code

Tue, 04/28/2009 - 12:48pm — Kyung
Dear all, It is a great honor to join W2 Forum. I have some questions on source code. What is the meaning of "BI(K,I)/BH2(K,I)"? I found above term in settling process in Generic Constituent I guess it is related to the depth of layer. However, I want to know the meaning of BI(K,I) and BH2(K,I). Furthermore, I'm finding the solar radiation at different depth. In manual,solar radiation at different depth is summarized as follow I=(1-BETA)*I0*EXP(-alpha*depth). So, Which variable is solar radiation at different depth in source code ?. Thanks
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Water Quality
Wed, 04/29/2009 - 4:27pm — chris

Hi Kyung, BI(k,i) is the cell width at layer k and segment i. BH2(k,i) is the product of cell width multiplied by cell height at layer k and segment i. There isn't a variable representing solar radiation at different layers, but this can be calculated by hard-wiring the code. Solar radiation at a layer k can be calculated by summing the light attenuated through the water column before reaching the layer at the specified depth. If you look at the kinetics subroutine, gamma(k,i) is the total light extinction for the cell at layer k and segment i. The light energy passing the water surface at segment I is calculated from: LIGHT = (1.0-BETA(JW))*SRON(JW)*SHADE(I) where shade(I) is the shade coefficient, beta(jw) is the fraction of incident radiation absorbed at the water surface, and SRON(jw) is the solar raditaion. Hope this helps, chris
Wed, 04/29/2009 - 5:39pm — Kyung

I deeply appreciate of your help. Have a nice time