Two-Phase Flow in Piping Components

Abstract

Two-phase and single-phase pressure drop data were obtained for flow in horizontal 5.08-cm-dia pipe and piping components that included: a 9.14-m straight section of pipe; a gate valve; an elbow; a combination of elbow and gate valve separated by different pipe lengths; a globe valve; a swing check valve; and a union. Single-phase pressure drops produced by each component were used to establish the resistance coefficient, K. This resistance was then used to calculate two-phase pressure drops for each component using the Tremblay and Andrews homogeneous flow model. An acceptable agreement was found between measured and predicted pressure drops for all piping components studied. Pressure recovery lengths for individual components were found to be 10–50 pipe diameters, depending on flow rates. The resistance coefficient of two components separated by a distance less than the recovery length was always greater than the summation of each individual resistance coefficient.

Non‐newtonian liquid flow through globe and gate valves

“…There are very few experimental data available in the literature, although pressure losses in valves are of considerable importance in the design and analysis of fluid machinery. Karr and Schutz (1940), Beck (1944), Piggot (1950Piggot ( , 1957, Kittredge and Rowlew (1957), Tremblay and Andrews (1974), Hooper (1981), Edwards et al (1985) and Sookprasong et al (1986) studied the pressure drop across different types of valves. Some of these studies were made by treating the valve as a piece of straight pipe, of the same physical length of the fitting, but the main drawback of this method is that it cannot predict the loss accurately.…”

Water–air flow in straight pipes and across 90∘ sharp-angled mitre elbows

“…data [46] Correlation (5) Correlation (6) Correlation (7) ( Fig. B.28 shows the comparison between our experimental data for the flow across the horizontal and horizontal to vertical mitre elbows for a wide range of flow conditions, listed in Tables 1 and 2, and the prediction given by the models proposed by Chisholm [7] and Sookprasong et al [10]. These models severely overpredict the pressure drops, especially at high flow rates.…”

“…Many researchers have proposed pressure-drop prediction models for two-phase flow in straight pipes [2,3,4,5,6], while a very limited number of models have been proposed for the pressure drop across 90 • round elbows [7,8,9,10] and 180 • bends [11,12]. Most of these models expressed the two-phase pressure drop in terms of a two-phase multiplier φ as:…”

Investigating the pressure loss associated with two-phase flow in a rectangular microchannel suddenly expanding into a manifold

“…14) with a mean absolute percent error of 81%. The models of Chisholm [50] and Sookprasong [54] produce smaller values, respectively. The model of Kuhn & Morris [53] breaks down at the lowest liquid velocity due to the inverse relationship of the model to ð1 À cÞ 2 .…”

“…Other authors have proposed relations based on the homogeneous flow model. Sookprasong et al [54] proposed:…”