First, thanks for sharing your idea. In my study, the variables (x,y) is directed along the horizontal and vertical directions. Also , the integral equation Int (V*dx) [0 Y*] =Y* is correct, where the value of Y* keeps changing. In the energy equation the additional term corresponds to viscous dissipation.
I don't have access to your article. Could you please send me a copy of your paper.
I got the analytical solution of the problem when the viscous dissipation is absent. My concern is how to relate the pressure drop and mass conservation equation integral form when I want to solve the equations numerically with viscous dissipation. In some papers, they mentioned that the pressure drop should be obtained from the integral continuity equation, but the details were not given.