Put name as vis (shortcut for viscosity) and click on OK. This will open a dialouge box and put the name for expression. And then go to Expressions, Functions and Variables and then right click on Expressions and click on insert to insert new expression. In order to define expression, go to tree outline. This is part of online course at udemy CFD course These material properties will be used to define the new custom material. Here I am giving one example of using expression to create expressions for density and viscosity. Here I have placed the some common variables with units, taken from CFX-Pre user guide. This is part of airfoil simulation in CFX (cfx file can be provided on request) similar drag and lift coefficients are defined from X and Y component of force receptively. Velocity in x and y direction are set as Uinf times the cos and sin components respectively. They are created from variables and also from other expressions. Here I have created expressions for different requirements. For power use ^ sign and -ve sign for the unit in denominator. In CEL, you must enclose units in square brackets, and give space between two units. For example velocity has units of meter per second. values can be dimensional or non dimensional. drag coefficientĬEL can be used to define values and expressions. Defining an expression for evaluation of derived variable in CFD Post, e.g.
Define material properties that depend on other variables.It is based on CFX expression language (CEL). CEL can be used to: