The response to external excitations in thermocapillary liquid layers

The responses to external excitations in thermocapillary liquid layers are investigated by non-modal stability theory. maximum amplification of input signals is measured a response function depending on the perturbation velocity and temperature. There can be rather large amplifications subcritical flows at both small Prandtl numbers (Pr). For Pr, increases significantly with Reynolds number (R) Biot (Bi) but decreases Pr. optimal achieved when almost spanwise wave. properties for linear flow return similar. caused combination lift-up mechanism, Orr forcing. However, could only found flow, while variations Pr Bi opposite those propagates streamwise direction. effect.