Rub-impact behaviors of a multistage bladed drum rotor under high time-varying temperature

•A rubbing blade-drum model under high time-varying temperature is proposed.•Paroxysmal vibrations caused by sudden temperature rise induce a rubbing fault.•The rub-impact fault is induced or intensified during fluctuating temperature rise.•Reducing a proper exhaust temperature weakens tip-rub and avoids shock vibrations.