Magnetohydrodynamic gravity - Capillary waves in a liquid film.
Magnetic field effect on Kapitza capillary traveling wave on falling conducting liquid film surface
Lu, P.-C.↗
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Unstable capillary waves on surface of separation of two viscous fluids
The study of the breakup of a liquid jet moving in another medium, for example, a jet of fuel from a nozzle, shows that for sufficiently large outflow velocities the jet breaks up into a certain number of drops of different diameters. At still larger outflow velocities, the continuous part of the jet practically vanishes and the jet immediately breaks up at the nozzle into a large number of droplets of varying diameters (the case of "atomization"). The breakup mechanism in this case has a very complicated character and is quite irregular, with the droplets near the nozzle forming a divergent cone.
JETS - ATOMIZATION↗
Growth and excitation of electrohydrodynamic surface waves.
Growth and excitation of surface waves on capillary liquid jet stressed by electric field
PLASMA PHYSICS↗
Breakup of Droplets in an Accelerating Gas Flow
A study of droplet breakup phenomena by an accelerating gas flow is described. The phenomena are similar to what propellant droplets experience when exposed to accelerating combustion gas flow in a rocket engine combustion zone. Groups of several dozen droplets in the 100-10 750-micron-diameter range were injected into a flowing inert gas in a transparent rectangular nozzle. Motion photography of the behavior of the droplets at various locations in the accelerating gas flow has supplied quantitative and qualitative data on the breakup phenomena which occur under conditions similar to those found in large rocket engine combustors. A blowgun injection device, used to inject very small amounts of liquid at velocities of several hundred feet per second into a moving gas stream, is described. The injection device was used to inject small amounts of liquid RP-1 and water into the gas stream at a velocity essentially equal to the gas velocity where the group of droplets was allowed to stabilize its formation in a constant area section before entering the convergent section of the transparent nozzle. Favorable comparison with the work of previous investigators who have used nonaccelerating gas flow is found with the data obtained from this study with accelerating gas flow. The criterion for the conditions of minimum severity required to produce shear-type droplet breakup in an accelerating gas flow is found to agree well with the criterion previously established at Rocketdyne for breakup in nonaccelerating flow. An extension of the theory of capillary surface wave effects during droplet breakup is also presented. Capillary surface waves propagating in the surface of the droplet, according to classical hydrodynamical laws, are considered. The waves propagate tangentially over the surface of the droplet from the forward stagnation point to the major diameter. Consideration of the effects of relative gas velocity on the amplitude growth of these waves allows conclusions to be made regarding rates of the droplet breakup processes and total time of the breakup process.
Dickerson, R. A.↗