The Theoretical Study On Effect Of Axial/Rotating Gas Streams On The Circular Liquid Jet Breakup Process

This paper first does the linear stability analysis on the Viscous circular liquid jet moving in a inviscid and incompressible axial/rotating gas medium in the international.The paper uses dynamic boundary conditions,the linearized Navier-Stokes equations and the linearized kinematic,separately employs the dot product of the gradient operator ??? with momentum equation method,get the n-order dimensionles dispersion relation.When the rotating gas component is zero,Through validating,the n-order dispersion relation and the n-order dimensionless dispersion relation are consistent;this declared the dimensionless dispersion relation is right.this paper also does the analysis on the inviscid and compressible ? ?z-??r-z-? gas,but because of mathematics,the Bessel equation can not be solved;while the z gas can get,just gas disturbance stress.Using the Fortran language to programm.By analysis,We could obtain the relation between the wave growth and the wave number in various condition by altering the parameters.The Weber number,Greek number,liquid velocity,Euler number,Reynolds number and so on play a vital role in the cylindrical film stability.Do the graphic,then analyse the linear stability of the cylinder film:All the single sinuous,varicose,twin and three surface wave type U,when the wave number increases,???_r,dom ?k_dom shows increase ?the wave growth increase and decrease later.The Weber number also influence the jet process,along with the Weber number's growth,the maximum growth number and the dominant wave number also increase,which maybe illustrate that the film is so easy to break up.In the article,compared varicose with sinuous,we could get the wave growth of varicose is smaller than sinuous,when the Weber number given.This illustrate the sinuous wave is more unsteady than the varicose.So the sinuous wave has more influence than varicose.The growth of surface wave in various orders are analysed in the article,we can learn the influence of the single thigh wave is better than the twin thighs wave or treble thighswave.As the liquid viscidity grow,the surface wave become more steady;with the increase of Euler number?the wave number?Reynolds number?the wave growth increase,and the cylinder film is so stable.The axial gas and the rotating gas more greater,the cylinder film more unsteady.At the rate of the same flow,the effect of rotating air flow on the fragmentation of circular jet is larger than that of axial flow.Under the action of the high speed airflow,the instability of the combined air is much larger than that of the single rotating air flow.when the speed of rotating gas is smaller,the influence of the wave form could be negligible;but when the speed of rotating gas is larger,the influence is remarkable.Varicose is more stable,and plays more important role than varicose on the circular liquid jet breakup process.