i need a fundamental application of boundary layer flow by considering effect of viscous heating (i.e What can be an application of a effect of viscous heating on boundary layer).
I understand you are referring to the effect of temperature on boundary layer at a given surface. If that is what you mean you can find applications in the thermal properties of alloys for blade design in propellers and fans especially for turbines and air crafts, heat exchangers, and possibly on energy efficient wall designs for rooms.