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Water Quality Impacting Temperature Calibration

Sun, 08/24/2014 - 3:44pm — Steven
Hello. I have had successful calibration of temperature for my model however when I turn on water quality (I am only modeling TDS at this point), it disrupts my temperature calibration causing the model to over-predict temperature in-pool. The TDS is under-predicted in-pool. Any guidance as to what might cause this is greatly appreciated. Steven
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Hydrodynamics
Mon, 08/25/2014 - 3:35pm — Amir

Hi Steven, This is an excerpt from manual "Total dissolved solids (TDS) affect water density and ionic strength, thereby affecting water movements, ...". Heat transfer is also a function of movement. But personally, I don't think changes in density has big effects. I am suspicions that the main reason for these changes in temperature is the light extinction coefficient (EX COEF). You can have the EX COEF in model in two ways . you can input values as a separate file or let the model to calculate them. The EX COEF is a function of algae, suspended solids and etc. There are lots of literature that count wind sheltering coeff, shading coeff and EX COEF as the main factors affecting water temperature in water bodies. I think EX COEF is calculated inside model , so you have two options, one is that you input the EX COEF separately and calibrate your model for temperature based on that an then start the water quality part. Or you have to calibrate the TDS and temperature together including EX COEF calibration as well. Amir