Two Phase Flow Patterns During Condensation of Steam in Micro-Tubes
نویسندگان
چکیده
Flow visualization of two phase flow pattern of steam during condensation process in separate horizontal quartz micro-tubes with inner diameter ranging from 70-675 m was conducted. Two main kinds of flow patterns were observed: annular flow and slug flow, which both were nearly symmetrical. The annular flow also can be divided into two kinds: annular flow and annular-wave flow. The effects of tube diameter and mass flux on the two phase flow pattern were discussed and the characteristics of two phase flow in micro-tubes were analyzed. The experimental results were compared with the criteria for two phase flow pattern transition in traditional large diameter tubes and the results indicated that the present data has a good agreement with Mandhane(1974) map, but the ranges of slug flow predicted by Taitel and Dukler(1976) model are obviously narrow and the stratified flow predicted by these three maps was not found at present experiments.
منابع مشابه
Numerical Analysis of Water and Air in Venturi Tube to Produce Micro-Bubbles
Two-phase flow regimes are affected by conduit position, alignment, geometry, flow direction, physical characteristics, and flow rate of each phase as well as the heat flux toward the boundaries. Due to the importance of two-phase flow, numerous regimes have been identified. The first step in studying micro-bubble formation inside a venturi tube is to recognize the type of flow regimes. In this...
متن کاملCorona discharge in the steam for electrostatically enforced condensation
The corona discharge in the steam is investigated theoretically and experimentally in means of implementation with the steam condenser for the improved phase-change rate. The considered phenomena include the nucleation of water vapor on mobile charge carriers, the electrohydrodynamic vapor flow toward the condenser wall and the thermodynamics of the charged micro-droplet. The average size of mi...
متن کاملEffect of Inserting Coiled Wires in Tubes on the Fluid Flow and Heat Transfer Performance of Nanofluids
In the present study, numerical study of Al2O3-water nanofluid flow in different coiled wire inserted tubes are performed to investigate the effects of inserting coiled wires in tubes on the fluid dynamic and heat transfer performance ofv nanofluids. The numerical simulations of nanofluids are performed using two phase mixture model. The flow regime and the wall boundary conditions are assumed ...
متن کاملReforming Integrated with Oxidation in Micro-Heat Exchanger Reactor with Circular Micro-Channels
Steam reforming integrated with oxidation of methanol was considered with numerical simulation. The parallel micro-channels with circular cross sections were used. Because when the catalytic deposited inside the rectangular micro-channels, it fills up the edges. Hence, the approximation of a cylindrical channel is appropriate. Effect of this changing in cross section was considered and results ...
متن کاملSensitivity analysis of the effective nanofluid parameters flowing in flat tubes using the EFAST method
In the present study, the effective parameters of water-Al2O3 nanofluid flowing in flat tubes are investigated using the EFAST Sensitivity Analysis (SA) method. The SA is performed using GMDH type artificial neural networks (ANN) which are based on validated numerical data of two phase modeling of nanofluid flow in flat tubes. There are five design variables namely: tube flattening (H), flow ra...
متن کامل