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HEAT AND MASS TRANSFER IN SYSTEMS

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A unique complex of large-scaled setups has been developed at the Institute for the study of heat and mass transfer in two-phase systems. The IR thermography, electric-chemical, and capacity methods, speed photography, and video shooting are being used to measure the local characteristics of two-phase multicomponent systems.
    A film condensation of vapor, under various geometry and regime parameters, was studied including porous and grained media. It was determined during vapor condensation on tube bundles, that vapor condensates on overcooled drops and jets in the intra tube space.
    Crisis and transition phenomena were studied during boiling under the conditions of free and forced convection in cryogenic liquids, freons, and other liquids. The instability of the bubble structure of evaporation was determined. When liquid is being heated above the threshold values, evaporation fronts are formed on the surface of the vapor bubble. These fronts propagate in a metastable liquid with a constant velocity, which by order, exceeds the velocity of a bubble growth.
    supersonic jet. A thin structure of a viscous sublayer was studied in a water flow on the basis of the stroboscopic visualization method developed at the Institute. A decrease in the friction loss was determined for the case when an insignificantly small amount of high polymers was added. Correlations between momentum and heat transfer near the heated surface were determined by synchronous measurements of instant velocity and temperature. The structure of the flow with a longitudinal pressure gradient was studied in detail for the alternating flow detachment from a streamlined surface. Various polymer additions and visco-elastic coatings were used as a high-effective control means for near-wall turbulence in a uniform liquid.
    During experiments in a wide range of Reynolds numbers from 3ґ106 to 108, a five-fold decrease in the total resistance was achieved for the studied models. A drastic decrease of high-frequent acoustic noises and pressure pulsation was revealed on a streamlined surface.
    Evolution of a space shape of the flow is being studied in the mode of thermal-gravitation convection with a rise of Rayleigh's number. The process of the laminar-turbulent transition for Prandtl numbers Pr > 5 is of a multistage character. The flow shape changes qualitatively with a rise in the temperature.

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The investigation circuit for hydrodynamics and heat transfer during the forced two-phase flow of cryogenic liquids.

The thermogram of liquid film flowing down a vertical plane with a local heat source of 6.5+13 mm.

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Гидродинамический канал для изучения струйных течений. The large hydrodynamic tube.

Гольдштик М.А., Штерн В.Н.
Гидродинамическая устойчивость и турбулентность, Новосибирск: Наука, 1977, 366 с.

Гольдштик М.А., Штерн В.Н., Яворский Н.И. Вязкие течения с парадоксальными свойствами, Новосибирск: Наука, 1989, 336 с.

Кутателадзе С.С., Леонтьев А.И.
Турбулентный пограничный слой сжимаемого газа, Новосибирск, 1968, 177 с.

Alekseenko S.V., Markovich D.M.
Local characteristics of impinging round jets // Proc.3 Int. Symp.Turb.Modelling Measurement, Crete.Greece, 1996.P.633-642.

Geshev P.I.
A linear model of close-to-wall turbulent transfer // Russ.J.Eng. Thermophys. 1993. V.3, no. 1. P.49-89.

Kulik V.M., Semenov B.N.
Initial section of time-dependence of the Toms effect for solutions of polyethylene oxide, Recent Developments in Turbulence Management, 1991, p. 309-321.

Kuz'min G.A.
Small-scale intermittency and renormalization group, Advances in Turbulence, VI, 1996, p. 243-246.

   
 

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