화학공학소재연구정보센터
Atomization and Sprays, Vol.24, No.2, 155-179, 2014
LINEAR STABILITY ANALYSIS OF AN ELECTRIFIED VISCOELASTIC LIQUID SHEET IN A VISCOUS GAS MEDIUM
A linear analysis is carried out to investigate the instability behavior of a viscoelastic planar liquid sheet moving through a viscous gas in an electric field. The inner liquid is assumed to have a high electric conductivity and the outer gas is assumed to an insulating dielectric. The liquid and gas velocity profiles are taken to account. The governing equations of the sinuous and varicose disturbances for electrified viscoelastic liquid sheets have been solved using the Chebyshev spectral collocation method. The corresponding numerical results are compared with those of the electrified Newtonian liquid sheets, which reveals that the disturbance growth rate on the electrified viscoelastic liquid sheets is greater than that on electrified Newtonian ones with the identical zero shear viscosity. The maximum growth rate and dominant wave number of disturbance waves in the sinuous and varicose modes have been obtained. The influences of the electrical Euler number, liquid Reynolds number, and other rheological parameters on the instability of the electrified viscoelastic sheets have been investigated. It is concluded that the disturbance growth rate of sinuous mode is greater than that of the varicose mode. The increase of the electrical Euler number, liquid Reynolds number, and gas-liquid density ratio can accelerate the breakup of viscoelastic liquid sheets. The increase of time constant ratio and the ratio of the distance between the horizontal electrode and liquid sheet to the liquid sheet thickness would dampen the break-up process.