OICC Press International Journal of Energy and Environmental Engineering 2251-6832 11 4 (December 2020) 2020 06 16 Calculation of the dissipation coefficient of the mechanical energy of moving fluid in the smooth cylindrical tube in a turbulent flow taking into account the turbulent viscosity 10.1007/s40095-020-00349-x EN Alla Yovchenko Department of Energy Technologies, Cherkasy State Technological University, Cherkasy, UA Sergii Bespalko Department of Energy Technologies, Cherkasy State Technological University, Cherkasy, UA Sviatoslav Poliakov Department of Energy Technologies, Cherkasy State Technological University, Cherkasy, UA Tymofii Veretilnyk Department of Mechanics, Printing Machines and Technology, Cherkasy State Technological University, Cherkasy, UA Ruslan Kapitan Department of Mechanics, Printing Machines and Technology, Cherkasy State Technological University, Cherkasy, UA Journal Article 2020 06 16 Abstract Using a three-layer turbulence model for a cylindrical tube, an analytical calculation of the dissipation coefficient of the mechanical energy of flow in a smooth-walled cylindrical tube was performed, taking into account the turbulent viscosity. To take into account the turbulent viscosity, the turbulence model developed by Y. V. Lapin, O. A. Nekhamkin and M. Kh. Strelets was applied, considering Van Driest’s damping multiplier. Analytical formulas were obtained describing the dependence of the dissipation coefficient of the mechanical energy of the flow on the number Re in the degree and logarithmic velocity distribution in a smooth cylindrical tube. Based on the performed calculations, a plot of the coefficient of dissipation on the number Re is constructed. The obtained results are consistent with the results obtained by other authors and are not inferior to modern, more complex mathematical models and can be used in engineering calculations. This analysis provides simple analytical expressions to determine the coefficient of dissipation concerning turbulent viscosity using a universal velocity profile in a smooth cylindrical tube.