Swing compressor, Vibration, Exciting force, Theoretical calculation
This study aims to theoretically analyze the rigid-body vibration in swing compressors. Currently, low noise and vibration (NV) are qualities recognized as a desired value for an air conditioner by end users. Because the compressor is one of the main sources of NV in an air conditioner, low NV compressors are needed. Designing a low NV compressor requires the understanding of the physical phenomena occurring in a compressor that contribute to NV. In this study, we theoretically analyzed rigid-body vibration, which has been one of the main phenomena causing NV in a swing compressor. Main factors causing rigid-body vibration in the swing compressor were classified into three types of excitation forces. By formulating them in a Fourier series representation, the primary and secondary components in the frequency domain were calculated for each excitation force without any numerical calculation method, including FFT. Furthermore, by multiplying the mass and inertial tensor of the compressor to this, we calculated both the amplitude and phase of the rigid-body vibration generated by each excitation force. We then confirmed that the calculated vibration was consistent with the experimental results. The contribution of each excitation force to the radial and tangential vibrations of typical swing compressors was theoretically analyzed. The results of the analysis clearly indicated that vibration was effectively reduced by not only simply reducing the magnitudes of the excitation forces but also by balancing the excitation forces.