A Computational Fluid Dynamicist's View of CWE

Publisher Summary In their desire to develop computational methods as design tools, people forget that no design method is perfect and that the errors inherent in any method need to be estimated. This chapter discusses the numerical errors and their estimation. Problems to be solved in computational wind engineering (CWE) are posed as a set of partial differential equations and boundary conditions. These might not represent the physics with sufficient precision because of modeling approximations but they have exact solutions; numerical errors are differences from these. Any quality numerical method, given enough resources, will produce this solution. To argue that one numerical method is always better than another because it gives a better solution to a particular problem is a waste of time. The important difference between methods is the issue of which method gives a more accurate solution for a given cost. Without estimates of numerical errors, designers could be in danger of believing inaccurate results and using them as the basis for a design. This is important when users are not sophisticated in computational fluid dynamics (CFD) techniques.