Processes of C1-C4 hydrocarbons gas separation with membranes yielding in methane and C3+ fractions are highly attractive. The significant breakthrough on this issue can be achieved by the development of novel gas separation modules based on C3+ hydrocarbons-selective hollow fiber membranes. The efficiency of this technology significantly depends on the module design, which should take into account the mass and heat transfer processes within the module with the simultaneous external constrained flow in the fiber system, the internal flow in hollow fibers, and molecular transport in the selective membrane layer. The developed simulation model includes the theory of convective diffusion transport in the shell-side constrained flow in hollow fiber membrane modules with an ordered arrangement of fibers. The simulated dependencies of the Sherwood number for circular fiber in a fiber row arranged in a transverse laminar flow on the Reynolds, Peclet and Schmidt numbers, and membrane mass transfer coefficient will be presented.