A common issue that arises in CFD is the validation and testing of the code to be used for a computation. The code can be a newly written one (the testing then is to determine if the code works properly), or it can be a commercial code (the testing then is to determine if the code is suitable for the task at hand). Some of the cases described in the article below are easy to solve, while others are more difficult.

When choosing a case for validation purposes, keep the following in mind:

• Don't try to do too much. If you have written a code, try the 2-D cases first. If you are testing a commercial code, it is probably best to try (vendor supplied) tutorial cases, and then move on to a test case that is like what the code will be expected to do.
• Some of these cases are still active areas of research, particularly for LES and the like.
• Don't rely just on the information here. The authoritative source is always the literature, so look at the references cited in the articles for definitive details.