In the era of process modeling of composite materials, 3D simulation of manufacturing processesis desirable considering the manufacturing trend where parts became more complexleading to complex 3D stress-strain states. Moreover, coupling of sub-processes that are happeningsimultaneously such as macro-scale preform processes, flow advancement and solidand fluid interaction requires full 3D description of the problem.The development is exemplified considering RTM process where the main focus of the modelingwill be on the flow advancement into fiber preform and flow front capturing. To thisend, the theory of two phase porous media is used along with assuming hyper-elastic materialresponse for the fiber bed to formulate the problem. A finite element formulation and implementationof the two-phase problem is developed for incompressible constituents