Numerical and Experimental Simulation of Two-Phase Tsunami Flow Through Buildings with Openings

During tsunami action on a structure, the structure is subjected to heavy loads with complex phenomena which include the interactions among tsunami, structure and air. In order to mitigate tsunami damages on structures, it is important to understand the characteristics of tsunami hydraulic loads acting on the structures with taking into account the above interactions. In the present study, the characteristics of tsunami forces on a building structure are investigated using a two-phase flow model. Two types of building models, a building without openings and with openings, were dealt with; and the effects of openings on the building under the tsunami hydraulic loads are examined. The simulation results were compared with the results obtained from one-phase flow simulation, and also verified with experimental data. The numerical results show good agreement with the measured ones. Furthermore, the effects of air taken into the flow and opening configuration on the characteristics of pressures and uplift forces were also discussed.

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

Journal of Energy Resources Technology ◽

10.1115/1.2905916 ◽

1992 ◽

Vol 114 (1) ◽

pp. 14-30 ◽

Cited By ~ 26

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.

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Data Analysis of Two-Phase Flow Simulation Experiment of Array Optical Fiber and Array Resistance Probe

Coatings ◽

10.3390/coatings11111420 ◽

2021 ◽

Vol 11 (11) ◽

pp. 1420

Author(s):

Shuaifei Cui ◽

Junfeng Liu ◽

Kui Li ◽

Qinze Li

Keyword(s):

Optical Fiber ◽

Flow Simulation ◽

Phase Flow ◽

Two Phase ◽

Fiber Probe ◽

Optical Fiber Probe ◽

Optical Fiber Probes ◽

Flow Through ◽

Water Cut ◽

Domestic Design

To solve the problem that traditional single-probe instruments cannot accurately measure the gas and water holdup, the domestic design of the array holdup measuring instrument Array of Optical and Resistance Tool (AORT), composed of five sets of optical fiber probes and five sets of resistance probes, is carried out in both gas–water and oil–water. Simulated measurement experiments were conducted under different water cut in phase flow. Through the analysis of the experimental data, the response relationship between the optical fiber probe and the resistance probe of the AORT instrument in different fluids was obtained. Then, the data under different conditions of fluid, flowrate and water cut in the experiment were compared by drawing. Interpolation algorithm was used to perform two-maintenance holdup imaging, and finally the holdup image was compared with the pictures of the flow in the pipe recorded during the experiment. The results show that the resistance probe has a better response under low water cut conditions, and the optical fiber probe has a better response under high gas cut conditions, which is consistent with the theoretical analysis. The imaging diagram and the flow pattern in the pipe during the experiment are in good agreement. It can be seen that the accuracy of the holdup measured by the AORT instrument under the test conditions is verified, and can provide technical support for further carrying out the measurement and interpretation of the holdup in future, as well as the improvement of the instrument and on-site testing.

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Numerical Simulation of Compacting Process of Green Sand Molding Based on Sand Filling

Materials Science Forum ◽

10.4028/www.scientific.net/msf.561-565.1879 ◽

2007 ◽

Vol 561-565 ◽

pp. 1879-1882

Author(s):

Wen Zhen Li ◽

Jun Jiao Wu

Keyword(s):

Flow Simulation ◽

Property Testing ◽

Phase Flow ◽

Hardness Distribution ◽

Green Sand ◽

Two Phase ◽

Molding Sand ◽

Sand Molding ◽

Sand Material ◽

Good Agreement

The mathematical models of compacting process in green sand molding were built up based on the experiment results of molding sand property testing, in which the nonlinearity problems involved in the molding sand material, the pattern geometry and the contact between sand and flask were considered. These models were then used to numerically simulate the compacting process of green sand and predict the hardness distribution of green sand mold. The effect of sand filling on the initial sand density distribution was taken into account, which was obtained through the two phase flow simulation of sand filling. The predicted results were compared with the measured ones and good agreement was obtained.

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