Research on the vibration analysis of the discharge pipe system in the outdoor unit of air conditioner

In this paper, an integration model of discharge pipe system in the outdoor unit of air conditioner has been developed, which include discharge chamber, discharge pipe and connecting pipe. The fluid-structure interaction (FSI) analysis method has been applied to study the effects of discharge velocity fluctuation and operating frequency (discharge frequency) on the stress in the discharge pipe. Based on the simulation of fluid domain, the inlet velocity of discharge pipe can be calculated, which is used as the inlet velocity for the FSI analysis of discharge pipe. The outlet pressure of discharge pipe for FSI analysis is also equal to the condensation pressure. The FSI simulation results show that both discharge velocity fluctuation and operating frequency have a significant effect on the stress in the discharge pipe. An increment of discharge velocity fluctuation leads to an increment of stress fluctuation amplitude and the increase of discharge frequency also results in the increase of stress fluctuation amplitude. To reduce the negative effects of discharge velocity fluctuation and the high discharge frequency, the discharge chamber with a large buffer volume is required for the actual application.