There have been a few studies on high viscosity mixing devices. However, there exists no universally accepted technique for evaluating their functional status in the light of generalized basis information such as the flow patterns, shearing and tensile deformation characteristics in the mixing equipment. The first part of this paper gives a physical meaning to the mixing number C₁=nT_M and the shearing amount, C₂ = T_M
（P_vg_c/μ）^-1/2 by using a simplified Mohr's striation thickness theory. The second part of this paper, the degree of surface renewal action is studied by comparing the value estimated from the flow patterns on a free surface of a liquid with that from a gas absorption chracteristics. The third part of this paper gives a review for heat transfer problems some considerations on discrepancies between different investigators in heat transfer problems Newtonian and non-Newtonian fluids.