Simulation Analysis of Fuel Pump Piston Oil Film Friction Heat Generation Based on CFD Method

Abstract

Aiming at the friction heat generation of fuel pump piston oil films for underwater gas turbines, combined with the computational fluid dynamics dynamic grid and slip grid methods, user-defined function programming is performed according to the piston motion equation. Furthermore, a fuel-pump piston oil-film simulation calculation model is established considering the viscosity-temperature characteristics of the oil. A modeling analysis method for the frictional heat generation of the piston oil film is presented. Using the proposed analysis method, the frictional heat generation of the piston oil film was simulated and analyzed, and the influences of the outlet pressure, wall temperature, and rotational speed on the temperature change caused by the oil film frictional heat generation were studied. The following conclusions are obtained. 1) When the inlet pressure was 0.5 MPa, the changes in the outlet pressure had little effect on the temperature rise of the oil film. Moreover, the temperature rise at the top of the oil film was the largest, and the temperature rise could reach up to approximately 4 K at the rate of 2 250 r/min. 2) In the range of 300 K to 373 K, the temperature increase at the top of the oil film decreased by approximately 50% for every 20 K increase in wall temperature. Moreover, the temperature increase at the top of the oil film at 373 K was only 9.2% of that at 300 K. 3) The temperature increase of the oil film and the rotation speed have an approximately linear relationship.

Keywords

• underwater gas turbine
• piston oil film of fuel pump
• friction heat generation