Predicting Distributor-Type Fuel Injection Pump Rotor Motion Using an Integrated Lubrication and Structural Dynamics Model

Abstract

A computer code was developed to analyze the rotor design of distributor-type fuel injection pumps used on diesel engines. The developed model integrates the three-dimensional rotordynamic motion solver and the two-dimensional lubrication solver. The instantaneous rotor motion within the bore can be predicted using an iterative approach. The lubrication model solves the transient, two-dimensional Reynolds equation implemented with Elrod's cavitation algorithm. A perturbation approach is used to construct the fluid film stiffness and damping matrices. The rotor's equations of motion are solved by the fourth-order Runge-Kutta method. Rotor elastic deformation due to external loading and film pressure effects is considered. Results indicate that the external loading is the primary cause of eratic motion on the rotor traces. Proper balance port design is also very important to avoid excessive rotor motion.

Presented at the 50th Annual Meeting in Chicago, Illinois May 14–19, 1995

KEY WORDS:

• Hydrodynamic lubrication

Notes

Presented at the 50th Annual Meeting in Chicago, Illinois May 14–19, 1995