How to Plan a CFD Analysis

Computational Fluid Dynamics (CFD) is now widely used in industry to simulate a very large range of industrial flow problems. It is used by engineers both as a complementary design and development tool and to help understand complex flow phenomena in existing flows. CFD can be an expensive and time-consuming technology. It should be applied with care and only to projects to which it can provide significant added value. Inappropriate use of such analysis tools can produce inaccurate and even incorrect results. Careful planning should minimise the risks of this occurring and ensure that the customer is aware of the level of accuracy that may be expected. To make the most use of this powerful tool it is necessary for the analyst to understand why a simulation is required, what output data are required, the necessary accuracy of the output data and at what locations those data will be required. Planning is necessary to enable the most suitable models for the flow under consideration to be selected and to ensure that any simplifications made are not likely to have a significant impact on the required output data. The amount of effort required for analysis planning will vary considerably depending on the type of analysis being conducted. Less planning is required for quick 'look-see' analyses for which a low level of accuracy and fewer data points are required. Large-scale analyses for which significant accuracy and several flow or geometrical variations are required will, of course, require considerable planning.