Numerical simulation of the torque characteristics of the hydro-coupling in the stop mode

Abstract

Introduction. The article considers an oil hydrodynamic retarder with an active diameter of 220 mm. The subject of the study is a comparison of two methods for constructing the moment characteristic of a hydraulic brake - the analytical solution of the Euler equation for turbomachines and the solution by the finite volume method in a three-dimensional formulation, considering flow turbulence. The object of study is the hydraulic clutch, which functions in the stop mode as a node of the auxiliary braking system of the car.

Objective. The purpose of the work is to substantiate the correctness of using the finite volume method for solving problems of this type, as well as to assess the effect of the flow rate passing through the fluid part of the hydraulic brake on its torque characteristic.

Methodology and methods. The features are considered and a comparison is made of two approaches to determining the torque coefficient, as well as constructing the torque characteristic of a hydraulic brake - based on the solution of the Euler equation for turbomachines and the CFD finite volume method.

Results and scientific novelty. It has been established that in the absence of coolant flow through the fluid coupling flow path, the results obtained using the considered methods are qualitatively and quantitatively consistent. The deviation of the results obtained using both methods does not exceed 5%.

Practical significance. In the course of the study, it was shown that the flow rate passing through the fluid coupling has a significant impact on the torque characteristic, as a result of which it was concluded that it is expedient to use a finite volume flow rate for solving this type of problem, if it is necessary to consider the flow of the working fluid through the hydraulic brake cavity.