On the impact of a concave nosed axisymmetric body on a free surface

Mathai, Varghese and Govardhan, Raghuraman N and Arakeri, VH (2015) On the impact of a concave nosed axisymmetric body on a free surface. In: APPLIED PHYSICS LETTERS, 106 (6).

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Abstract

We report on an experimental study of the vertical impact of a concave nosed axisymmetric body on a free surface. Previous studies have shown that bodies with a convex nose, like a sphere, produce a well defined splash with a relatively large cavity behind the model. In contrast, we find that with a concave nose, there is hardly a splash and the cavity extent is greatly reduced. This may be explained by the fact that in the concave nosed case, the initial impact is between a confined air pocket and the free surface unlike in the convex nosed case. From measurements of the unsteady pressure in the concave nose portion, we show that in this case, the maximum pressures are significantly lower than the classically expected ``water hammer'' pressures and also lower than those generally measured on other geometries. Thus, the presence of an air pocket in the case of a concave nosed body adds an interesting dimension to the classical problem of impact of solid bodies on to a free surface. (C) 2015 AIP Publishing LLC.

Item Type:	Journal Article
Publication:	APPLIED PHYSICS LETTERS
Publisher:	AMER INST PHYSICS
Additional Information:	Copy right for this article belongs to the AMER INST PHYSICS, 1305 WALT WHITMAN RD, STE 300, MELVILLE, NY 11747-4501 USA
Keywords:	WATER ENTRY; SPHERES
Department/Centre:	Division of Mechanical Sciences > Mechanical Engineering
Date Deposited:	20 Apr 2015 07:23
Last Modified:	25 Feb 2019 05:27
URI:	http://eprints.iisc.ac.in/id/eprint/51246

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