Setting a fully developed flow in a periodic duct.
Sometimes, it is necessary to set a fully developed flow in a periodic domain (i.e. with no 'flow' boundaries). Often, the requirement is to achieve a specified mass flow rate or mean velocity. This may be achieved by setting a momentum source, whose value is automatically set by a user Fortran routine, such that the required conditions are met. This example shows how to automatically set a momentum source to achieve a specified volume weighted mean velocity in a periodic duct. This results in a fully developed velocity profile along the entire length of the duct. A number of control paramters are specified as user parameters in the command language: target velocity : the target velocity control param : control parameter initial source : initial value for the momentum source frequency : iteration frequency at which the source is updated Using the values given, convergence is achieved in solver 300 iterations. A complete example is provided. The attached zip archive contains all required files. To run the example: - Create the user Fortran shared library: cfx5mkext -name test usr_cal_source.F usr_set_source.F - Modify the command language, such that the user Fortran shared library path is correct.- Update the definition file: cfx5cmds -def hexduct1.def -text hexduct1.ccl -write - Run the solver: cfx5solve -def hexduct1.def **** Entered By: dsclarke @ 05/18/2006 12:31 PM **** |
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