## How to Solve a Classic CFD Benchmark: The Lid-Driven Cavity Problem

##### Angela Straccia May 8, 2018

The lid-driven cavity is a popular problem within the field of computational fluid dynamics (CFD) for validating computational methods. While the boundary conditions are relatively simple, the flow features created are quite interesting and complex. Here, we demonstrate how to define this benchmark problem in the COMSOL MultiphysicsÂ® software. We also showcase techniques like mapped meshing and nonlinearity ramping, which can be applied to a wide variety of CFD models.

Read More##### Angela Straccia December 30, 2016

There are many ways to experimentally measure pressure in a fluid. When setting up a CFD model, it is important to use the correct definition of pressure for assigning boundary conditions and defining the material properties. Today, we’ll explain the difference between relative and absolute pressure, why the COMSOL MultiphysicsÂ® software solves CFD problems using relative pressure, and when to use each definition of pressure in your models.

Read More##### Angela Straccia March 29, 2016

Are you solving turbulent flow problems in your CFD analyses? Then you may be familiar with the large computation time that can result from difficulties in finding the numerical solution. Such difficulties are caused by nonlinearities that arise in the turbulence model equations. Viscosity ramping can help decrease the computation time by solving for higher viscosities and using the solutions as initial conditions for the problem at lower viscosities. We’ll show you how to implement this technique in COMSOL Multiphysics.

Read More