scholarly journals Complex network community structure of two-phase flow pattern and its statistical characteristics

2008 ◽  
Vol 57 (11) ◽  
pp. 6909
Author(s):  
Gao Zhong-Ke ◽  
Jin Ning-De
Keyword(s):  
Community Structure ◽  
Flow Pattern ◽  
Complex Network ◽  
Two Phase Flow ◽  
Statistical Characteristics ◽  
Phase Flow ◽  
Two Phase ◽  
Network Community

Micro-Scale Flow Pattern Classification Based on the K-Means Clustering Algorithm

2010 ◽  
Author(s):  
Daniel Sempe´rtegui ◽  
Gherhardt Ribastki
Keyword(s):  
Flow Pattern ◽  
High Speed ◽  
Clustering Algorithm ◽  
Two Phase Flow ◽  
Flow Boiling ◽  
Saturation Temperature ◽  
Flow Patterns ◽  
Statistical Characteristics ◽  
Phase Flow ◽  
Two Phase

In the present work, an objective method to characterize two-phase flow pattern was developed and implemented. The method is based on the characteristics of the signals provided by transducers measuring local temperature and pressure plus the intensity of a laser beam crossing the two-phase flow. The statistical characteristics of these signals were used as input features for the k-means clustering method. In order to implement the method, experimental flow patterns were obtained during flow boiling of R245fa in a 2.32 mm ID tube. Experiments were performed for mass velocities from 100 to 700kg/m2s, saturation temperature of 31 °C and vapor qualities up to 0.99. The cluster classification was compared against flow patterns segregated based on high speed camera images (8000 images/s) and a reasonable agreement was obtained.

Upward Vertical Two-Phase Flow Through an Annulus—Part II: Modeling Bubble, Slug, and Annular Flow

1992 ◽  
Vol 114 (1) ◽  
pp. 14-30 ◽  
Author(s):  
E. F. Caetano ◽  
O. Shoham ◽  
J. P. Brill
Keyword(s):  
Flow Pattern ◽  
Annular Flow ◽  
Two Phase Flow ◽  
Flow Behavior ◽  
Bubble Flow ◽  
Phase Flow ◽  
Two Phase ◽  
Flow Through ◽  
Physical Phenomena ◽  
Good Agreement

Mechanistic models have been developed for each of the existing two-phase flow patterns in an annulus, namely bubble flow, dispersed bubble flow, slug flow, and annular flow. These models are based on two-phase flow physical phenomena and incorporate annulus characteristics such as casing and tubing diameters and degree of eccentricity. The models also apply the new predictive means for friction factor and Taylor bubble rise velocity presented in Part I. Given a set of flow conditions, the existing flow pattern in the system can be predicted. The developed models are applied next for predicting the flow behavior, including the average volumetric liquid holdup and the average total pressure gradient for the existing flow pattern. In general, good agreement was observed between the experimental data and model predictions.

Two-Phase Flow and Heat Transfer in Rectangular Micro-Channels

2003 ◽  
Author(s):  
Weilin Qu ◽  
Seok-Mann Yoon ◽  
Issam Mudawar
Keyword(s):  
Heat Transfer ◽  
Pressure Drop ◽  
Flow Pattern ◽  
Two Phase Flow ◽  
Flow Patterns ◽  
Heat Sinks ◽  
Phase Flow ◽  
Micro Channel ◽  
Two Phase ◽  
Micro Channels

Knowledge of flow pattern and flow pattern transitions is essential to the development of reliable predictive tools for pressure drop and heat transfer in two-phase micro-channel heat sinks. In the present study, experiments were conducted with adiabatic nitrogen-water two-phase flow in a rectangular micro-channel having a 0.406 × 2.032 mm cross-section. Superficial velocities of nitrogen and water ranged from 0.08 to 81.92 m/s and 0.04 to 10.24 m/s, respectively. Flow patterns were first identified using high-speed video imaging, and still photos were then taken for representative patterns. Results reveal that the dominant flow patterns are slug and annular, with bubbly flow occurring only occasionally; stratified and churn flow were never observed. A flow pattern map was constructed and compared with previous maps and predictions of flow pattern transition models. Annual flow is identified as the dominant flow pattern for conditions relevant to two-phase micro-channel heat sinks, and forms the basis for development of a theoretical model for both pressure drop and heat transfer in micro-channels. Features unique to two-phase micro-channel flow, such as laminar liquid and gas flows, smooth liquid-gas interface, and strong entrainment and deposition effects are incorporated into the model. The model shows good agreement with experimental data for water-cooled heat sinks.

scholarly journals Flow Pattern and Pressure Drop Characteristics on Gas/Liquid Two-phase Flow in a Serpentine Capillary Tube

2007 ◽  
Vol 2 ◽  
pp. 25-32 ◽  
Author(s):  
Toru SUKAWA ◽  
Tomoya HASEGAWA ◽  
Kenji YOSHIDA ◽  
Isao KATAOKA
Keyword(s):  
Pressure Drop ◽  
Flow Pattern ◽  
Two Phase Flow ◽  
Capillary Tube ◽  
Phase Flow ◽  
Two Phase
Sign in / Sign up

Export Citation Format

Share Document