Numerical modelling of tube system nonlinear dynamics

Abstract
This paper presents numerical method for estimation of heat-exchanger tube bundle vibration with account of impacts of tubes in clearances with tube support grids in liquid cross-flow. The proposed numerical model permits to determine a stressed-strained state and vibro-wear parameters being initial ones for realized modification of structure durability diagnostics. Tube-bundle vibration induced by liquid cross-flow represents a grave obstacle to overcome while manufacturing high-efficiency heat exchangers. Due to this fact the experimental and theoretical investigations are performed which have to clear up the main reasons for tube vibration in flow. The paper describes special mathematical model, which may be applied for prediction of tube-bundle response under the action of hydroelastic and vortex excitation mechanisms. The estimated parameters of stressestrained state and vibro-contact are used as initial ones for structure durability prediction.