Simulation of two-dimensional squeeze film and solid contact forces acting on a heat exchanger tube

Based on a short-length cylindrical squeeze film model, a simplified two-dimensional dynamic model for the interaction of a heat-exchanger tube and its support, with transitions to and from solid contact, has been developed. The model includes estimations of the tube/support deflection, the effects of the surface roughnesses and tube/support inclination. A test computer code based on the model has been developed which calculates the normal and tangential squeeze film forces and solid contact forces acting on the tube with large amplitude arbitrary motions. As well, the code has been extended to simulate a mass with six degrees of freedom. The model and algorithm have been verified by numerical analysis and comparisons. The VIBIC finite-element computer code which simulates the dynamic response of a heat exchanger tube as it impacts and rubs against its supports has been improved and updated by implementing the test code into it. The simulation results appear reasonable