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北京大学正在设计β=0.09,频率为 162.5 MHz taper型的二分之一波长射频超导谐振腔(HWR腔),这种腔针对高流强质子束(约 100 mA)和氘束(约 50 mA)的加速而设计.对于这种超导腔而言机械性能分析是十分重要的,可以通过机械性能分析来估计由于腔体的形变带来的频率偏移.用 ANSYS分析了由于液氦压力不稳定造成的麦克风效应以及洛伦兹力造成的腔体失谐,并且对沿腔体轴线方向的调谐进行了分析.模拟结果显示这只腔压力敏感系数为 3 1 .1 Hz/kPa,洛伦兹力系数为-0.41 Hz/(MV·m-1 )2.腔体的调谐范围达到±177 kHz,足够补偿腔体可能的频率偏移.腔体的机械性能满足腔体正常运行的要求.,Peking University is designing a superconducting taper-type half-wave resonator (HWR)with frequency of 162.5 MHz andβof 0.09 for high current proton beam (about 100 mA)and deuteron beam (about 50 mA)acceleration.For this kind of SRF cavity,mechanical analysis is important to predict the frequency shift caused by the cavity deformation.ANSYS codes are used to analyse the frequency shift caused by helium bath pressure and Lorentz force,and the tuning range.Simulation results show that this HWR cavity has pres-sure sensitivity as low as 31.1 Hz/kPa and Lorentz force detuning coefficient of -0.41 Hz/(MV·m-1 )2 .The tuning range of the cavity is ±177 kHz which is wide enough for compensating the possible frequency shift. The mechanical property of the cavity permits the cavity’s stable operation.