Accession Number : AD0011504


Title :   INCIPIENT-CAVITATION SCALING EXPERIMENTS FOR HEMISPHERICAL AND 1.5- CALIBER OGIVE-NOSED BODIES


Descriptive Note : Joint study


Corporate Author : CALIFORNIA INST OF TECH PASADENA HYDRODYNAMICS LAB


Personal Author(s) : PARKIN, BLAINE R ; HOLL, J W


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/011504.pdf


Report Date : 15 May 1953


Pagination or Media Count : 43


Abstract : A visual determination was made of the incipient cavitation number for 2 families of geometrically similar, axially symmetric bodies in steady rectilinear flows at various free-stream velocities and dissolved-air contents. The incipient cavitation number specifies that point at which cavitation disappears as the static pressure is slowly increased at a constant free-stream velocity. One family consisted of right-circular cylindrical bodies with hemispherical noses; the other had 1.5-cal ogive noses. The hemispherical- and ogive-nose models has o.25- to 8-in. and 0.5- to 4-in. diameters, respectively. The tunnel velocity was held constant, and the free-stream static pressure was lowered until cavitation was established around the entire nose. The pressure was then raised until incipient cavitation was observed. The free-stream static pressure and velocity were recorded. Curves are included of the incipient-cavitation number vs free-stream velocity for each model size. The over-all agreement with previous test results (CIT Hydrodynamics Laboratory Reports, 21-7 and E-35.1) was considered satisfactory. The conventional method of calculating the incipient-cavitation index was believed to be invalid. The data indicated that the incipient cavitation number for each family of models is representable as a function of the product of the flow velocity and the square root of the model size. Tabulated test data are appended as well as head-form and mounting-arrangement details.


Descriptors :   *CAVITATION , EXPERIMENTAL DATA , COMPUTATIONS , SIZES(DIMENSIONS) , MODELS , REPORTS , TUNNELS , FLOW RATE , AXISYMMETRIC , TABLES(DATA) , LABORATORIES , AGREEMENTS , FREE STREAM , HEMISPHERES , HYDRODYNAMICS , NOSES , STATIC PRESSURE , SQUARE ROOTS , TEST AND EVALUATION , VELOCITY


Subject Categories : Fluid Mechanics


Distribution Statement : APPROVED FOR PUBLIC RELEASE