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Energy Balance

Fri, 08/08/2003 - 2:08pm — Eric
I am starting a model of a resevoir and I am going through the snapshot files to verify that the model is reading in what I expect. Using the time series output and storage capacity curves I was able to achieve an accurate water balance. But unfortunately the energy balance shows that I have an unacceptable percent error. I looked through the manual for some clues on what to do, but I did not find much. Do you have any advice on what I might do or is there somewhere I can look to find more info on energy balances. Thanks[addsig]
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Hydrodynamics
Mon, 08/18/2003 - 1:24pm — Tom

What do you mean by unacceptable? What are the values you are getting?[addsig]
Tue, 08/19/2003 - 10:36am — Eric

Sorry, I should have been more precise. I understand that the percent error should be on the order of 10^-8 to 10^-13, but the percent error I am getting for the energy balance is around the order of 10^-1. Thanks, Eric[addsig]
Wed, 08/20/2003 - 7:31am — Tom

Eric, you have to be careful interpreting the percent error. If the change in energy is small, the percent error can be very high but will not be of concern. For example using the volume balance, if the total change in volume is < 1000 m^3 for a reservoir in which the water level is maintained constant, then a percent error of 1x10^2 is not uncommon, but should not be a cause for concern.[addsig]