Application of the Eigenfrequency of a Convective Cell to Determination of the Frequency Characteristics of Oscillatory Thermal Gravitational and Thermocapillary Convection in Closed Volumes

Abstract

The notion of the eigenfrequency of a convective cell has been introduced and three methods for determination of this parameter in numerical experiments have been proposed. The effect of resonance of the stream function in the field of a rotating gravity vector (this effect has been found earlier) is used for thermal gravitational convection in a square cavity. Thermocapillary convection is investigated in a rectangular cavity and in a cylinder. In these cases use is made of the resonance effect and the variation of the parameters with eigenfrequency under the action of a heat flux harmonically oscillating and acting on the free surface of the liquid. The correspondence between the obtained eigenfrequencies of the convective cell and the frequencies of oscillatory convection, obtained in numerical calculations and experiment, has been established.