I am working on a project, where the material of the housing is changed from C15 (Low carbon steel) to Nylon GF60%, we found the material serves satisfactory for the given loading condition, but the problem is with heat dissipation.

Purpose of the housing is to support the shaft, which rotates at 25000 RPM with 500gms axial load and 2.5Kg radial load (i.e. Belt tension) (Please refer the Image),
Housing is filled with lubricating Oil of viscosity 10 cStokes.

Here I need to calculate the minimum thermal conductivity required for housing material.