I am trying to compute 3D flow (Navies-Stoke eq.). But I don't know which method is better, explicit method or implicit method?

Also, what's kind of calculation algorithm of implicit method is popular and suitable, can anyone kindly give me a hint?

I do need your help.

Thank you very much!

Well, this is a quite large question. Please decide whether your case is incompressible or compressible. For the former one, SIMPLE series methods are very popular. For the later one, especially when the Mach number is larger, time-marching method is recommended.

Besides, may be you should think about the accuracy you wish. Then, you have choices among Reynolds averaged equations methods, Large Eddy Simulation method and also Direct Numerical Simulation method.

Concerning the explicit and implicit method, it depends on the algorithm you use. For the SIMPLE method, implicit method is popular.