the pressure drop of refrigerant r-134a flow boiling inside a horizontal tube has been investigated experimentally. the test set-up which was used in this investigation is a well instrumented vapor compression refrigeration system. these instruments are thermocouples, flow meter, pressure gauges and the pressure drop measuring apparatus. this system consisted of three electrically heated evapor...

a method based on electrical capacitance tomography (ect) and an improved least squares support vector machine (ls-svm) is proposed for void fraction measurement of oil-gas two-phase flow. in the modeling stage, to solve the two problems in ls-svm, pruning skills are employed to make ls-svm sparse and robust; then the real-coded genetic algorithm is introduced to solve the difficult problem of ...

Although two-phase flow is frequently encountered in various location of the process plants, there is no a general accepted and verified two-phase flow model that may be used to size lines for such conditions. An obvious example is condensate water return lines. The API method that used in this study is based on the homogeneous equilibrium flow assumption, that is, equal velocity and equal temp...

the produced liquid water in cathode catalyst layer (ccl) has significant effect on the operation of proton exchange membrane fuel cell (pemfc). to investigate this effect, the transport of oxygen in ccl in the presence of immiscible liquid water is studied applying a two-dimensional pore scale model. the ccl was reconstructed as an agglomerated system. to explore the wettability effects, diffe...

in this study, gas evolution in a vertical electrochemical cell is investigated numerically with a modified two-fluid model. the mathematical model involves solution of separate transport equation for the gas and liquid phases with an allowance to inter-phase transfer of mass and momentum. the governing equations are discreted via the finite volume technique and then are solved by the simple al...

coriolis mass flow meters are one of the most accurate tools to measure the mass flow in the industry. however, two-phase mode (gas-liquid) may cause severe operating difficulties as well as decreasing certitude in measurement. this paper presents a method based on fuzzy systems to correct the error and improve the reliability of these sensors in the presence of two-phase model fluid. definite ...

in many industrial equipment such as boilers and heat exchangers, the cylindrical tubes are exposed to the gas- liquid two phase flow. for any immersed body in flow field vortex shedding is created with a frequency that may be constant or variable, according to conditions such as flow rates, geometry of body, and etc. the failure will happen in the equipment, when this frequency is close to one...

in this research, the effect of surface roughness and bubble injection on skin friction and hydrodynamic drag force has been numerically considered. this research is based on taylor-couette flow. considered flow includes two concentric cylinders which internal cylinder is movable and external is immovable. the effective equations on the flow includes: equations of momentum, continuous, turbulen...

in this research, numerical simulation of a symmetric impact of a 2-d wedge, considering dynamic equations in two-phase flow is taken into account. the two-phase flow around the wedge is solved based on finite volume method and volume of fluid (vof) scheme. the dynamic mesh model is used to simulate dynamic motion of the wedge, thereby the effects of different dynamic meshes in both structured ...