Ninf is a middleware for building a global computing system in wide area network environments. We designed and implemented a Ninf computational component, netCFD for CFD (Computational Fluid Dynamics). The Ninf Remote Procedure Call (RPC) provides an interface to a parallel CFD program running on any high performance platforms. The netCFD turns high performance platforms such as supercomputers and clusters into valuable components for use in global computing. Our experiment shows that the overhead of a remote netCFD computation for a typical application was about 10\% comparing with its conventional local execution. The netCFD applet GUI which is loaded in a web browser allows a remote user to control and visualize the CFD computation results interactively.