Experimental study of momentum transfer in a cellular flame of rich and lean propane-butane/air mixture

AbstractIn this experimental study, the ablative Richtmyer–Meshkov (RM) and the Rayleigh–Taylor (RT) instabilities were generated by the laser pulse of Gaussian-like power profile. The initial multi-modal perturbation, the inhomogeneous momentum transfer and different Atwood numbers generate different shapes of spikes and bubbles in the central region (CR) and the near-central region (NCR) of the spot. A one-dimensional Gaussian-like power profile causes the formation of the wavy-like rows of aperiodic spikes. The periodic spike segments inside the rows appear due to locally coherent flow. In the NCR, the mushroom-shape spikes tend to the organization on the isotropic square and the anisotropic rhombic lattices. The increase of the lattice periods two, three, or four times indicates formation of superstructures. The growth of sharp asymmetric RM/RT spikes in the CR is fast, uncorrelated and linear, while the growth of the symmetric mushroom-shape ones in the NCR is slow, correlated, and nonlinear.

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Mass flow and momentum flux in nanoporous membranes in the transitional flow region

Physical Chemistry Chemical Physics ◽

10.1039/d1cp02797b ◽

2021 ◽

Author(s):

Dmitrii I. Petukhov ◽

Stepan K Podgolin ◽

Thomas Loimer ◽

Andrei A. Eliseev

Keyword(s):

Experimental Study ◽

Momentum Transfer ◽

Mass Flow ◽

Momentum Flux ◽

Flow Region ◽

Transitional Flow ◽

Nanoporous Membranes

An experimental study of momentum transfer in nanoporous polymeric track-etched membranes with pore diameters ranging from 100 to 1300 nm and nanochannel length of 12-20 µm was performed using He,...

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Experimental study of cooling spray for physiotherapeutic treatment

Russian Journal of Physiotherapy Balneology and Rehabilitation ◽

10.17816/1681-3456-2020-19-1-6 ◽

2020 ◽

Vol 19 (1) ◽

pp. 40-43

Author(s):

Antonina V. Butorina ◽

Sergei B. Nesterov ◽

Nikolay A. Andreev

Keyword(s):

Thin Film ◽

Experimental Data ◽

Experimental Study ◽

Temperature Distribution ◽

Analgesic Effect ◽

Gas Mixture ◽

Temperature Level ◽

Propane Butane

For cooling damaged areas of biotissue in order to achieve a rapid analgesic effect, a procedure for applying a thin film to the skin, boiling at a temperature of T0 = 273238 K of a gas mixture, is widely used. This temperature is achieved when using a cooling spray. Experimental data on the temperature distribution on the cooled surface when throttling a propane/butane/R123 mixture from a nozzle with a diameter of 0.5 mm to the temperature level Т0 = 240; 263; 270 К, used for physiotherapy purposes, are presented. A comparison of the efficiency of cooling the skin using a cryopresponder and using ice was also made. It is shown that cooling with a cooling spray is more efficient.

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