VOID FRACTION AND WAKE ANALYSIS OF A GAS-LIQUID TWO-PHASE CROSS-FLOW

Two-phase cross-flow takes place in a wide range of industrial equipment, including heat exchangers and measurement devices. The aim of this paper is to establish a numerical model and experimental methodology for comprehensive study and visualization of void fraction and wake region in gas-liquid cross-flow over immersed bodies with various cross-section geometries. Conservation of mass and momentum for both-phase free streams, along with constitutive relationships, were used for modeling turbulence. The input parameters for the numerical simulations were two-phase Reynolds number, free-stream void fraction, bubble size in the inlet, and cross-section geometry of prisms inserted in the two-phase flow path. Because the wake region and phase distribution around an immersed object are time-dependent, we report time average values of drag, lift, and pressure coefficients. The results show that drag and lift coefficients are strongly dependent on the two-phase Reynolds number; this dependency is a more moderate function of void fraction. The results are in good agreement with available empirical correlations and experimental work. Furthermore, experiments were conducted to visualize phase distribution and wake region in two-phase cross-flow. Comparison of the experimental and numerical results verifies the developed numerical model.

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