Discussion and conclusion
The vibrational characteristics of the piping structures in air conditioner outdoor unit have been investigated by performing an impact hammer test. A numerical FE model is set up to correlate with the measured results. The main focus of this work is to investigate the dynamic stiffness of compressor-piping mounting for the vibration behaviour determination in the FE approach. The dynamic stiffness of compressor-piping mounting is represented by the dynamic stiffness of rubber grommet sitting beneath the compressor. This characterization reduces the initial 6 translational stiffness of both elastic end supports to 3 unknown stiffness variables at the other end of the tube mounting to valve at chassis. Parameter fine tuning is applied to obtain better correlation with experimental data.