How to check if right volume source is being applied to a fluid zone?
A linearly varying energy source term is to be applied to a fluid zone. In order to make sure the total source term is correct, the function has to be integrated over the fluid volume. Here is how to check if the coefficient in the following relation produces the correct volume source distribution along the zdirection. An example is used below where 14.65 MW is to be extracted out of a fluid zone of volume (~7.8 m^3) If the udf, the source term is described as: source= 20.068*(117059.45933.81*z); In the above equation, 20.068 is the coefficient that can be altered to get a different amount of energy removal. Create a custom field function. DefineCustom Field Function. In the function panel, you have to use the mouse pointer to enter the above formula i.e. click the following buttons on the calculator screen that pops up with DefineCustom Field Function:  2 0 . 0 6 8 and so on until you are done. To enter z, use the field function dropdown menu, scroll down and click on Grid. Under Grid, scroll down and click on zcoordicate. Then click on Select button under it. Finish the formula by clicking the right paranthesis. Click Create to create cutom function0. You may give it any other name too. Next, go to ReportVolume Integrals panel. Here you will click on volume integral under options and select custom field function in the field function drop down menu. Click on the fluid zone where this source will be applied. Click Compute. It will give you the total energy source in the fluid zone. If this number is not what you want to remove, adjust the coefficient and recreate your custom field function with the new coefficient. Repeat the process. mks 

