Falling film evaporation on horizontal tubes with smooth and structured surfaces
نویسنده
چکیده
منابع مشابه
Dominant Flow Mechanisms in Falling-Film and Droplet Mode Evaporation Over Horizontal Rectangular Tube Banks
Flow visualization with high-speed video of evaporating water films falling over flat horizontal tubes, representative of the external surfaces of microchannel tubes, is presented. Experiments were conducted with 1.4 mm thick and 27 mm tall tubes over a film Reynolds number range of 23 < Re < 126. In addition to a qualitative description of the flow mechanisms, this work quantifies key droplet ...
متن کاملImproving Heat Transfer in Falling Film Evaporators in Food Industries
Falling film evaporators, due to their high heat transfer coefficients, low energy loss, rather a low holdup time, and the ability to handle high capacities have broad applications in food industries. Thus, this kind of evaporator is being used in the production of temperature sensitive compounds such as syrups. In this study, through modelling of the falling film evaporator with the use of...
متن کاملVapor Shear Effects on Falling-Film Mode Transitions Between Horizontal Tubes
A liquid falling between horizontal tubes can take the form of droplets, jets, or a continuous sheet mode, depending on the flow rate. The so-called falling-film flow regime is important to heat and mass transfer, and to maintaining wetted-surface conditions in a falling-film tube bundle, and the performance of such tube bundles is important in many air-conditioning systems. In this paper, we r...
متن کاملExperimental Study on the Heat Transfer Performance of a Zeotropic Refrigerant Mixture in Horizontal Tubes
In the present study, the condensation and evaporation heat transfer performance of a zeotropic refrigerant mixture (HFC32/HFC125/HFC134a) inside horizontal tubes with smooth, grooved or cross·grooved inner surfaces was investigated experimentally. The cross-gTOoved tube showed the highest heat transfer coefficient for both condensation and evaporation with the zeotropic mixture. Its heat trans...
متن کاملNumerical and Analytical Approach for Film Condensation on Different Forms of Surfaces
This paper tries to achieve a solution for problems that concern condensation around a flat plate, circular and elliptical tube in by numerical and analytical methods. Also, it calculates entropy production rates. At first, a problem was solved with mesh dynamic and rational assumptions; next it was compared with the numerical solution that the result had acceptable errors. An additional suppor...
متن کامل