Applied Computational Fluid Dynamics Techniques: An Introduction Based on Finite Element Methods, 2nd Edition

15 EFFICIENT USE OF COMPUTER HARDWARE

However clever an algorithm may be, it has to run efficiently on the available computer hardware. Each type of computer, from the PC to the fastest massively parallel machine, has its own shortcomings that must be accounted for when developing both the algorithms and the simulation code. The present section assumes that the algorithm has been selected, and identifies the main issues that must be addressed in order to achieve good performance on the most common types of computers. The main types of computer platforms currently being used are as follows.

(a) Personal computers. Although perhaps not considered a serious analysis tool even a decade ago, personal computers can already be used cost-effectively for 3-D simulations. In fact, many applications where CPU time is not a constraining factor are currently being carried out on PCs. Most CFD software companies report higher revenues from PC platforms than from all other platforms combined. High-end PCs (4 Gbytes of RAM, 120 GFLOPS graphics card) are ideal tools for simulations. We see this as one more proof of the theme that has been repeated so often in this book: a CFD run is more than just CPU – if this were so, vector machines would have become the dominant type of computer. Rather, it consists of problem definition, grid generation, flow solver execution and visualization. High-end PCs combine a relatively fast CPU with good visualization hardware, allowing to cut down the most expensive ...