## Calculate Swirl Strength

Problem: How do I calculate the Swirling Strength criterion (Lambda-Ci)? Solution: Use a Tecplot Macro to automate the calculation. Make sure Tecplot is aware of the variables representing your velocity field (Analyze->Field Variables menu). The commands are as follow: Calculate the tensor of velocity gradients. This command can be obtained by recording the Analyze->Calculate Variables…->Velocity Gradient (tensor) action in Tecplot’s user interface (UI). $!EXTENDEDCOMMAND COMMANDPROCESSORID = ‘CFDAnalyzer4’ COMMAND = […]