# Accession Number:

## AD0630244

# Title:

## THE USE OF RATIONAL APPROXIMATIONS IN THE DIRECT CALCULATION OF SUPERSONIC FLOW PAST A BLUNT BODY OF REVOLUTION,

# Descriptive Note:

# Corporate Author:

## NAVAL ORDNANCE LAB WHITE OAK MD

# Personal Author(s):

# Report Date:

## 1966-02-15

# Pagination or Media Count:

## 44.0

# Abstract:

A method using rational approximations is presented for calculation of the supersonic axially symmetric flow of a perfect gas around a given blunt body. The method involves an iteration of the solution of the inverse problem, and matches the bluntness of the calculated body at the nose with that of the given one. The solution of the inverse problem is carried out using certain Pade fractions formed from the Taylor expansion of the stream function in the neighborhood of the nose of the shock. Rational approximations are obtained for the flow quantities on the body in terms of the arc length measured from the nose. In the present approximations, the computing time on the IBM 7090 is about sixty milliseconds for the solution of the inverse problem, and less than a second for the direct problem. Good agreement with measurements and other calculations is found in the subsonic region when the bluntness of the given body is less than or equal to that of a sphere. Examples indicate that the body should not be much blunter than a sphere in the present approximation if reasonable accuracy is desired near the sonic line. Author

# Descriptors:

# Subject Categories:

- Fluid Mechanics