Accession Number : AD0128957


Title :   WATER-ENTRY CAVITY MODELING. PART I. VERTICAL CAVITIES


Corporate Author : NAVAL ORDNANCE TEST STATION CHINA LAKECA


Personal Author(s) : WAUGH, J G ; STUBSTAD, G W


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/128957.pdf


Report Date : 08 Oct 1956


Pagination or Media Count : 61


Abstract : Modeling studies were conducted with a 2 inch diameter hemisphere head missile as a prototype and with 1- and l/2-inch-diameter models of the prototype. This modeling with models program was carried out to investigate the importance of gas density scaling in conjunction with Froude and cavitation number scaling in water entry cavity modeling. The observation of the cavities formed by the vertical entry of those model. showed that one-to-one scaling of the Froude and cavitation numbers and of the gas density coefficient modeled the cavity to a high degree of accuracy. Failure to scale the cavitation number did not prevent good modeling. but when the gas density coefficient was not scaled modeling did not occur. Good water penetration distance modeling obtained for all modeling conditions. Evaluation of the importance of atmospheric density scaling on water entry modeling must be deferred until tests are extended to include launchings of models at oblique angles. Cavitation number scaling cannot be disregarded in the general water entry modeling problem because it has been found necessary to model missile motion in oblique water entry.


Descriptors :   *GUIDED MISSILES , *WATER ENTRY , DENSITY , MODEL TESTS , SCALING FACTOR , CAVITATION , BODIES OF REVOLUTION , FROUDE NUMBER


Subject Categories : Fluid Mechanics
      Guided Missile Dynam, Config & Cntrl Surfaces


Distribution Statement : APPROVED FOR PUBLIC RELEASE