computational requirements to write own cfd prog!

yogi

hi guys.. well.. i had some doubts in mind before i start writing my own cfd program.. 1: how logical/helpful is it to write our own cfd code ( in my case its 'turbulence modellling over a bluff body at the free surface')instead on using softwares like FLUENT AND FIDAP? 2: assuming i start writing my own code.. what computational requirements would i need? a workstation or a PC hardware requirements. 3: as for the question on FLUENT capability i would like to ask how rigorous is the turbulence modelling in FLUENT?considering the fact that i am concentrating on the turbulence effects at the free surface this is quite important for my study.

hey .. would like to thank in advance for all ur replies and suggestions.. bye and regards yogi