Hydrodynamic Impact Analysis of a Cylinder

Cointe, Raymond; Armand, J L

doi:10.1115/1.3257015

Cited by 173 publications

(77 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…the impact of a rigid body striking the surface of still water (Batchelor, 1973;Cointe & Armand, 1987;Cointe, 1989;Howison et al, 1991;Wagner, 1932). Pressure-impulse theory, applied to the changes in a moving liquid domain that collides with a fixed structure, was introduced by Cooker and Peregrine (1995).…”

Section: 2! Pressure-impulsementioning

confidence: 99%

Three-dimensional steep wave impact on a vertical cylinder

2016

View full text Add to dashboard Cite

The present study treats the three-dimensional hydrodynamic slamming problem on a vertical plate subjected to the impact of a steep wave moving towards the plate with a constant velocity. The problem is complicated significantly by assuming that there is a rectangular opening on the plate which allows the discharge of the liquid. The analysis is conducted analytically assuming linear potential theory. The examined configuration determines two boundary value problems with mixed conditions which should be taken into account properly. The mathematical process assimilates the plate with a degenerate elliptical cylinder allowing thus the employment of elliptical harmonics that ensure the satisfaction of the free-surface boundary condition of the front face of the steep wave, beyond the plate. This assumption leads to an additional boundary value problem with mixed conditions in the vertical direction. The associated problem involves triple trigonometrical series and it is solved through a transformation into integral equations. To tackle the boundary value problem in the vertical direction a perturbation technique is employed. Extensive numerical calculations are presented as regards the variation of the velocity potential on the plate at the instant of the impact which reveals the influence of the opening. The theory is extended to the computation of the total impulse exerted on the plate using pressure-impulse theory.

show abstract

Section: 2! Pressure-impulsementioning

confidence: 99%

Three-dimensional steep wave impact on a vertical cylinder

2016

View full text Add to dashboard Cite

show abstract

“…= 0.5 , shows that it grows quadratically with respect to the half wetted breadth c. By assuming a constant entry speed and neglecting the effect of the gravity, the slamming force/pressure and the free surface profile have been widely studied [1][2][3][4][5][6][7][8]. Under the influence of the slamming force, the freefall wedge experiences a rapid change of vertical acceleration.…”

Section: Introductionmentioning

confidence: 99%

Experimental and numerical investigation of a freefall wedge vertically entering the water surface

Wang

Lugni

Faltinsen

2015

Applied Ocean Research

View full text Add to dashboard Cite

Experiments and numerical methods are developed to investigate the water entry of a freefall wedge with a focus on the evolution of the pressure on the impact sides (the side contacting water) and the top side (the dry side on the top of the wedge), evolution of the global hydrodynamic loads, evolution of the air-water interface, and wedge motion. It is found that a typical water entry of a freefall wedge can be divided into slamming, transition, collapse and post-closure stages. A single-fluid numerical model is presented to simulate the first three stages. The results are compared to experiments and good agreements are obtained. A two-fluid BEM is proposed to investigate the influence of the air flow before the closure of the cavity created on the top of the wedge. It is found that for the closure of the 2D cavity, the air flow starts to play an important role just before closure but due to the short duration, the influence of air flow on the body velocity and configuration of the air-water interface is limited.

show abstract

“…Cisim daha yüksek enerjiye sahip olduğunda ise, yani cisim ile serbest su yüzeyi arasındaki yükseklik arttırıldığında (50 cm) yüzeyle etkileşim halindeki su belirli bir mesafe cismin yüzeyini takip ettikten sonra stabilitesi bozulduğu için yüzeyden ayrılmakta ve suya transfer edilen enerji daha yüksek olduğundan dolayı daha büyük kütlede yığıntılar cisimden dışarıya doğru uzaklaşmakta ve cismin arkasında kavite oluşmasına neden olmaktadır. Suya giren cisim transfer ettiği enerjisinin yarısını yükselen suya (jet flow) verirken kalan yarısını da yığıntılardaki (pileup) su kütlesine vermektedir (Cointe ve Armand [12]). Panciroli ve diğ.…”

Section: Deney Düzeneği Ve Metodolojiunclassified