The Theoretical And Experimental Studies On Power Transmission By Fluid Oil Film Shearing

With the rapid development of productivity and the increasing promotion of modernization, the consumption of energy is being greatly increased, which may lead to energy crisis or the rising of the price of energy. As a result, the target of energy saving has been a more and more emergent task.As a new type of power transmission device utilizing the shear of oil of film between two sets of discs. It is widely used for speed regulation and energy saving in large fans and pumps.This thesis explores the mechanism of oil film shearing power transmission of HVD using the theoretical analysis, fluid simulation and some experimental studies. Meanwhile, the thesis gives some possible reasons for the steady state speed fluctuation of the hydro-viscous drive in its practical running. The main contents of this thesis can be summarized in the following aspects.Chapter 1 mainly introduces the background and significance of the research theme, including the performance of the hydro-viscous and the advantage of the use of hydro-viscous. It also introduce of the development of the hydro-viscous at home and abroad.Chapter 2 mainly focuses on the theoretical analysis of the mechanism of oil film shearing power transmission of HVD, applying a new method of theoretical analysis, exploring in two ways the reasons for the steady state speed fluctuation of the hydro-viscous drive in its practical running. One is from the aspect of fluid dynamic stability of the flow field between two sets of discs, trying to analyze the stability of the flow field itself. The other consider the influence of temperature of oil film shearing force on the oil viscosity, leading in the temperature-viscosity function and a non-Newtonian fluid model representing the shearing-thinning fluid, and trying to get the variation rule of viscosity and the friction torque transmitted.Chapter 3 carries out the fluid simulation utilizing commercial software FLUENT on the basis of the theoretical analysis above. The results include the radial and circumferential pressure and temperature distribution of the flow field and the fluid-solid coupled field, as well as the comparison of the flow field under isothermal condition and that with the temperature-viscosity function and a non-Newtonian fluid model , through which to explore the variation rule of the flow field dynamic...