ul. Onezhskaya 8, Moscow, 125438, Russia
Keldysh Research Center
Safronov A. A.
Investigation of the Structure of Waves Generated by a $\delta$-perturbation of the Surface of a Capillary Jet
2022, Vol. 18, no. 3, pp. 367-378
The wave capillary flow of the surface of an inviscid capillary jet, initiated by a single $\delta$-perturbation of its surface, is studied. It is shown that the wave pattern has a complex structure. The perturbation generates both fast traveling damped waves and a structure of nonpropagating exponentially growing waves. The structure of self-similar traveling waves is investigated. It is shown that there are three independent families of such self-similar solutions. The characteristics of the structure of nonpropagating exponentially growing waves are calculated. The characteristic time of formation of such a structure is determined.
Safronov A. A., Koroteev A. A., Filatov N. I., Safronova N. A.
Capillary Hydraulic Jump in a Viscous Jet
2019, Vol. 15, no. 3, pp. 221-231
Stationary waves in a cylindrical jet of a viscous fluid are considered. It is shown that when the capillary pressure gradient of the term with the third derivative of the jet radius in the axial coordinate is taken into account in the expression, the previously described self-similar solutions of hydrodynamic equations arise. Solutions of the equation of stationary waves propagation are studied analytically. The form of stationary soliton-like solutions is calculated numerically. The results obtained are used to analyze the process of thinning and rupture of jets of viscous liquids.
Safronov A. A., Koroteev A. A., Filatov N. I., Grigoriev A. L.
The Effect of Long-Range Interactions on Development of Thermal Waves in the Radiation-Cooling Dispersed Flow
2018, Vol. 14, no. 3, pp. 343-354
The influence of long-range interactions on the progress of heat waves in the radiationcooling disperse flow is considered. It is shown that the system exhibits oscillations attendant on the process of establishing an equilibrium temperature profile. The oscillation amplitude and the rate of oscillation damping are determined. The conditions under which the radiation cooling process can be unstable with respect to temperature field perturbations are revealed. The results of theoretical analysis and numerical calculation of the actual droplet flow are compared.