Pressure drop two phase flow

TWO-PHASE FLOW PRESSURE DROP (GAS-LIQUID) ESTIMATION... 

Ishehara, K,J. W. Palen, andj. Taborek, Critical Review of Correlations for Predicting Two-Phase Flow Pressure Drop Across Tube Banks, Heat Trans. Eng.,Y. 1, No. 3,Jan.-March (1980). 

Steady-State, Two-Phase-Flow Pressure Drop... 

S.5.2 Transient two-phase-flow pressure drop. Calculation of transient behavior in a complex flow network containing a compressible fluid in two-phase states was... 

Jallouk, P. A., 1974, Two-Phase Flow, Pressure Drop and Heat Transfer Characteristics of Refrigerants in Vertical Tubes, Ph.D. thesis, University of Tennessee, Knoxville, TN. (4)... 

Johannessen, T., 1972, A Theoretical Solution of the Lockhart and Marinelli Flow Model for Calculating Two-Phase Flow Pressure Drop and Hold-up, Int. J. Heat Mass Transfer 75 1443. (3)... 

Related Calculations. Homogeneous flow method. Two-phase flow pressure drop can also be calculated using a homogeneous-flow model that assumes that gas and liquid flow at the same velocity (no slip) and that the physical properties of the fluids can be suitably averaged. The correct averages are... 

I. Select the appropriate equation. Two-phase-flow pressure drop for flow across tube bundles may be calculated using the equation... 

R. C. Xin, A. Awwad, Z. F. Dong, and M. A. Ebadian, An Experimental Study of Single-Phase and Two-phase Flow Pressure Drop in Annular Helicoidal Pipes, Int. J. of Heat and Fluid Flow, in press. 

Shellside Pressure Drop. Surprisingly little attention has been devoted in engineering literature to estimate two-phase pressure drop on the shell side of shell-and-tube heat exchangers [77, 78]. In engineering practice, the estimation of the two-phase flow pressure drop can be performed in some situations using modified single-phase flow correlations. This approach is, however, highly unreliable. 

In Table 17.22, two correlations are presented for shellside two-phase flow pressure drop estimation, based on modifications of the internal flow correlations. The first correlation uses the modified Chrisholm correlation [69, 79], and the second one [80] employs the modified Lockhart-Martinelli correlation. The first correlation is for horizontal crossflow (crossflow in a baffled horizontal heat exchanger with horizontal or vertical baffle cuts). The second one is for vertical crossflow (upflow in a horizontal tube bundle). 

The two-phase flow pressure drops are the direct sum of three contributions the static pressure drop Ap, the momentum pressure drop Apm and the frictional pressure drop Apf. For a horizontal tube, there is no change in static head so Aps = 0. The momentum pressure drop reflects the change in kinetic energy of the flow. Both may be obtained using an appropriate void fraction relation. Thus, the major goal of microscale studies on pressure drop is to find an empirical correlation or simplified concept to correlate the two-phase frictional pressure drops. 

Sun L, Mishima K Evaluation analysis of prediction methods for two-phase flow pressure drop in mini-channels. Int. J. Multiphase Flow 2009 35(1) 47-54. 

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