Numerical Prediction and Risk Analysis of Hydraulic Cavitation Damage in a High-Speed-Flow Spillway

Hydraulic cavitation is usually an undesirable phenomenon since it can damage the concrete surface of a chute spillway. In order to numerically predict the potential cavitation of a high-speed flow in a chute spillway, a compound risk assessment is proposed by combining probabilistic analysis with a computational fluid dynamics (CFD) technique. Based on the local pressure and flow velocity of the nodes, the traditional cavitation number is introduced to characterize the possibility of cavitation. The distribution of cavitation numbers was obtained according to the numerical simulation of the flow field in an open spillway. A hydraulic experiment was conducted to validate the numerical result. As a result, the potential cavitation region could be shown by visualizing the numerical result. Comparing the numerical results with the experimental results, hydraulic model validates the numerical simulation. The proposed numerical approach is economical and saves time; moreover, it can provide greater information about the potential cavitation region. This approach is more convenient for designers in their efforts to optimize the spillway shape and protect the concrete structure from cavitation erosion while maintaining lower costs and achieving higher visualization.

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Numerical Simulation of Direct Current Glow Discharges for High-Speed Flow Control

Journal of Propulsion and Power ◽

10.2514/1.24403 ◽

2008 ◽

Vol 24 (5) ◽

pp. 916-922 ◽

Cited By ~ 20

Author(s):

Jonathan Poggie

Keyword(s):

Numerical Simulation ◽

Flow Control ◽

Direct Current ◽

High Speed ◽

High Speed Flow ◽

Glow Discharges ◽

Speed Flow

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Features of high-speed aircraft numerical simulation

Engineering Journal Science and Innovation ◽

10.18698/2308-6033-2020-1-1946 ◽

2020 ◽

Author(s):

M.M. Alekseeva ◽

N.A. Brykov ◽

I.A. Vikhrova

Keyword(s):

Numerical Simulation ◽

Gas Dynamics ◽

High Speed ◽

Simulation Method ◽

High Speed Flow ◽

Flight Tests ◽

High Speeds ◽

Physical Experiments ◽

Speed Flow ◽

Flow Around A Body

Currently, the creation of new high-speed aircraft is of great interest. The development of such aircraft is associated with the need for experiments and flight tests. The organization of real physical experiments in the field of high speeds is fraught with significant difficulties that can be solved using the numerical simulation method, which makes it possible to significantly simplify the process of creating new products. When developing a high-speed aircraft, it is necessary to take into account the specific aerodynamic and thermophysical features of the processes occurring on the surface of the aircraft and in the shock layer. In this paper, the features of the processes at high speeds are considered on the example of solving the external and internal problems of the gas dynamics of an aircraft. Based on the specifics of these processes, we built a mathematical model that allows us to study the aerodynamics of a high-speed flow around a body in dense layers of the atmosphere and the processes that occur in the combustion chamber.

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Numerical Simulation of Non-Equilibrium Plasma Discharge for High Speed Flow Control

Journal of The Institution of Engineers (India) Series C ◽

10.1007/s40032-016-0314-1 ◽

2016 ◽

Vol 98 (3) ◽

pp. 285-293 ◽

Cited By ~ 2

Author(s):

Ramakrishnan Balasubramanian ◽

Karupannasamy Anandhanarayanan ◽

Rajah Krishnamurthy ◽

Debasis Chakraborty

Keyword(s):

Numerical Simulation ◽

Flow Control ◽

High Speed ◽

Plasma Discharge ◽

High Speed Flow ◽

Equilibrium Plasma ◽

Speed Flow ◽

Non Equilibrium

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Experimental Study on the Mechanism of the Combined Action of Cavitation Erosion and Abrasion at High Speed Flow

International Journal of Concrete Structures and Materials ◽

10.1186/s40069-019-0374-8 ◽

2019 ◽

Vol 13 (1) ◽

Cited By ~ 1

Author(s):

X. Wang ◽

Y. A. Hu ◽

Z. H. Li

Keyword(s):

Mass Loss ◽

High Speed ◽

Cavitation Erosion ◽

Concrete Surface ◽

High Speed Flow ◽

Single Action ◽

Speed Flow ◽

Combined Action ◽

Sand Particles ◽

The Impact

AbstractA new experimental method on simulating the combined action of cavitation erosion and abrasion was proposed to investigate the erosion mechanism of overflow structure induced by the said processes. An automatic sand mixing device was invented for high-pressure and high-speed flow based on the characteristics of Venturi cavitation generator and hydraulic Bernoulli principle. The experimental system for the combined action of cavitation erosion and abrasion was designed and constructed, and high-speed sand mixing flow only appeared in the test section. A series of tests on the combined and single action of cavitation erosion and abrasion on hydraulic concrete and cement was carried out by using the invented experimental device. Results show that the wear of concrete surface exhibited the combined characteristics of cavitation erosion and abrasion under their joint action. The damage degree of concrete surface under the combined action was more severe than that under a single action. The mass loss of concrete under the combined action was higher than sum of mass losses of concrete under two single actions. The promotion and enhancement between cavitation erosion and abrasion existed in high-speed sand mixing flow. A power exponential relationship was observed between erosion mass loss and flow speed, and the velocity indexes approximated 4.5. Small and light sand particles easily follow water flow. Thus, the strong coupling effect of cavitation erosion and abrasion resulted from the presence of small sand particles. Given the different mechanisms of cavitation erosion and abrasion, presenting the skeleton structure formed by cavitation erosion was notably difficult under the action of abrasion. Meanwhile, abrasion wear easily occurred under the impact of cavitation erosion, and this result is due to the mechanism of the combined action of both processes.

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