When does the heat generated by fluid friction becomes appreciable compared to the heat transferred between the fluids?

Question

Quizplus · Accepted Answer

At high fluid velocity, the friction between the fluid layers increases, leading to a significant generation of heat. This is because the energy from the fluid motion is converted into heat due to the viscous dissipation caused by the frictional forces within the fluid.

When Does the Heat Generated by Fluid Friction Becomes Appreciable