Two-Phase Flow in Piping Components

1986 ◽  
Vol 108 (3) ◽  
pp. 197-201 ◽  
Author(s):  
P. Sookprasong ◽  
J. P. Brill ◽  
Z. Schmidt
Keyword(s):  
Single Phase ◽  
Gate Valve ◽  
Flow Model ◽  
Check Valve ◽  
Resistance Coefficient ◽  
Two Phase ◽  
Pressure Drops ◽  
Globe Valve ◽  
Acceptable Agreement ◽  
Phase Pressure

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.

Prediction of Two-Phase Pressure Drop and Density Distribution From Mixing Length Theory

1963 ◽  
Vol 85 (2) ◽  
pp. 137-150 ◽  
Author(s):  
S. Levy
Keyword(s):  
Single Phase ◽  
Continuous Medium ◽  
Phase System ◽  
Mixing Length ◽  
Test Results ◽  
Two Phase ◽  
Pressure Drops ◽  
Mixing Length Theory ◽  
Phase Pressure ◽  
Good Agreement

Single-phase turbulent mixing length methods are used to predict two-phase flow. Two-phase density and velocity distributions and two-phase pressure drops are derived by treating the two-phase system as a continuous medium where the turbulent exchanges of momentum and density are equal. Good agreement is obtained between test results and analytical predictions.

Investigation on Hydraulic Resistance of Steam Generator Tube Support Plates

2014 ◽  
Author(s):  
Ting Xiong ◽  
Bo Wen ◽  
Yuanfeng Zan ◽  
Xiao Yan
Keyword(s):  
Experimental Data ◽  
Pressure Drop ◽  
Hydraulic Resistance ◽  
Steam Generator ◽  
Single Phase ◽  
Empirical Correlations ◽  
Two Phase ◽  
Flow Area ◽  
Pressure Drops ◽  
Phase Pressure

In order to obtain the hydraulic resistance characteristics of steam generator (SG) tube support plates (TSP), experimental as well as CFD studies have been carried out on both the single-phase and two-phase hydraulic resistances of various trefoil or quatrefoil orifice plates. Results show that with the increase of the Renylod number, the single-phase pressure drop coefficient decreases firstly and remains almost constant later. The single-phase pressure drop coefficient decreases with the increase of the chamfer radius of orifice or flow area. The two-phase pressure drops predicted by the empirical correlations are generally larger than the experimental results, while the pressure drops predicted by CFD software agree with the experimental data.

scholarly journals Experimental Investigation of the Vertical Upward Single- and Two-Phase Flow Pressure Drops Through Gate and Ball Valves

2019 ◽  
Vol 142 (2) ◽  
Author(s):  
Ammar Zeghloul ◽  
Hiba Bouyahiaoui ◽  
Abdelwahid Azzi ◽  
Abbas H. Hasan ◽  
Abdelsalam Al-sarkhi
Keyword(s):  
Experimental Investigation ◽  
Pressure Drop ◽  
Single Phase ◽  
Gate Valve ◽  
Two Phase Flow ◽  
Phase Flow ◽  
Flow Conditions ◽  
Two Phase ◽  
Pressure Drops ◽  
Flow Pressure

Abstract This paper presents an experimental investigation of the pressure drop (DP) through valves in vertical upward flows. Experiments were carried out using a 1¼″ (DN 32) ball and gate valve. Five opening areas have been investigated from fully open to the nearly fully closed valve, using air with a superficial velocity of 0–3.5 m/s and water 0.05–0.91 m/s. These ranges cover single-phase and the bubbly, slug and churn two-phase flow regimes. It was found that for the single-phase flow experiments, the valve coefficient increases with the valve opening and is the same, in both valves, for the openings smaller than 40%. The single-phase pressure drop increases with the liquid flowrate and decreases with the opening area. The two-phase flow pressure drop was found considerably increased by reducing the opening area for both valves. It reaches its maximum values at 20% opening for the ball valve and 19% opening for the gate valve. It was also inferred that at fully opening condition, the two-phase flow multiplier, for both valves, has been found close to unity for most of the tested flow conditions. For 40 and 20% valve openings the two-phase multiplier decreases in the power-law with liquid holdup for the studied flow conditions. Models proposed originally for evaluating the pressure drop through an orifice in single-phase and two-phase flows were also applied and assessed in the present experimental data.

scholarly journals Single-Phase and Two-Phase Pressure Drops over Return Bend in Rectangular Microchannel

2013 ◽  
Vol 26 (5) ◽  
pp. 595-602 ◽  
Author(s):  
Akimaro KAWAHARA ◽  
Michio SADATOMI ◽  
Satoshi SHIMOKAWA ◽  
Haslinda KUSUMANINGSIH
Keyword(s):  
Single Phase ◽  
Two Phase ◽  
Rectangular Microchannel ◽  
Pressure Drops ◽  
Phase Pressure

Evaluation of Cooling Performance of Ultrafine Cryoprobes: Effect of Probe Structure on Thermodynamic Properties of Refrigerant

2018 ◽  
Vol 26 (02) ◽  
pp. 1850020 ◽  
Author(s):  
Junnosuke Okajima ◽  
Sangkwon Jeong ◽  
Shigenao Maruyama
Keyword(s):  
Experimental Data ◽  
Flow Model ◽  
Thermodynamic Characteristics ◽  
Vapor Quality ◽  
Two Phase ◽  
Cooling Performance ◽  
Pressure Drops ◽  
Large Pressure ◽  
Different Dimensions ◽  
Phase Pressure

In this study, the effect of the structure of an ultrafine cryoprobe on its cooling performance was evaluated experimentally and numerically. To clarify the thermodynamic characteristics of the refrigerant in the ultrafine cryoprobe, three ultrafine cryoprobes with different dimensions were manufactured. Additionally, a phase change flow model was developed to estimate the refrigerant condition in a microchannel and evaluate the cooling characteristics of an ultrafine cryoprobe. For validating the numerical model, the results were compared with experimental data and a suitable empirical correlation for a two-phase pressure drop was determined. By calculating the refrigerant condition in an ultrafine cryoprobe, it is clarified that large pressure drops occur in the inner tubes and the refrigerant becomes subcooled owing to heat exchange between the flows in the inner and outer tubes. The temperature differences for three different cryoprobes are reproduced by the developed model. By changing the dimensions of the tubes comprising the ultrafine cryoprobes in the calculation, the lowest temperature can be determined. Additionally, freezing experiments are conducted, and the importance of temperature and vapor quality in ultrafine cryoprobes is represented in the time variation of the frozen region.

Two-phase pressure drops in largediameter pipes

AIChE Journal ◽  
1957 ◽  
Vol 3 (3) ◽  
pp. 321-324 ◽  
Author(s):  
R. C. Reid ◽  
A. B. Reynolds ◽  
A. J. Diglio ◽  
I. Spiewak ◽  
D. H. Klipstein
Keyword(s):  
Two Phase ◽  
Pressure Drops ◽  
Phase Pressure

Stratified flow model for two-phase pressure drop prediction in trickle beds

AIChE Journal ◽  
1988 ◽  
Vol 34 (3) ◽  
pp. 510-513 ◽  
Author(s):  
J. Biswas ◽  
G. V. Bhaskar ◽  
P. F. Greenfield
Keyword(s):  
Pressure Drop ◽  
Flow Model ◽  
Stratified Flow ◽  
Two Phase ◽  
Trickle Beds ◽  
Phase Pressure

Development of Sodium Two-Phase Flow Model for KALIMER Core Analysis

2002 ◽  
Author(s):  
W. P. Chang ◽  
Dohee Hahn
Keyword(s):  
Liquid Metal ◽  
Single Phase ◽  
System Analysis ◽  
Flow Model ◽  
Two Phase Flow ◽  
Water System ◽  
Phase Flow ◽  
Two Phase ◽  
Applicable Range ◽  
Further Development

An algorithm for sodium boiling is developed in order to extend the applicability of SSC-K, which is a main system analysis code for the KALIMER (Korea Advanced LIquid MEtal Reactor) conceptual design. As the capability of the current SSC-K version is limited to simulation of only a single-phase sodium flow, its applicable range should not be enough to assess the fuel integrity under some of HCDA (Hypothetical Core Disruptive Accident) initiating events where sodium boiling is anticipated. The two-phase flow model similar to that used for the light water system is known to be no more effective directly to liquid metal reactors, because the phenomena observed between two reactor coolant systems are definitely different. The developing algorithm is based on a multiple-bubble slug ejection model, which allows a finite number of bubbles in a channel at any time. The present work is a continuous effort following the former study to confirm a qualitative acceptance on the model. Since the model has been applied only to the active fuel region in the former study, a part of its qualification seems to have already been demonstrated. For its application to the whole KALIMER core channel, however, the model needs to be examined the applicability to the fuel regions other than the active fuel. The present study primarily focuses on that point. In a result, although the model may be improved in a sense through the present study over the previous modeling, a clear limitation is also confirmed with the validity of the model. The further development, therefore, is required for this model to achieve its goal by resolving such limitations.

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