# Accession Number:

## AD0434823

# Title:

## BASE PRESSURE BEHIND TWO-DIMENSIONAL AND AXIALLY SYMMETRIC BACKWARD FACING STEPS IN A TURBULENT SUPERSONIC FLOW,

# Descriptive Note:

# Corporate Author:

## TECHNION - ISRAEL INST OF TECH HAIFA

# Report Date:

## 1963-12-01

# Pagination or Media Count:

## 30.0

# Abstract:

The pressure behind a two-dimensional step in supersonic turbulent flow is calculated by the use of the Crocco-Lees momentum integral method. However, instead of assuming a constant mixing rate of k0.03, it is assumed that C, the average value of turbulent mixing rate correlation function between separation and shock impingement positions, is constant. This assumption considers the turbulent mixing to be similar, in general, to the laminar case except for the much higher mixing rate. The assumption of C, as constant leads to a similarity parameter for the pressure behing a two-dimensional step equal to Re sub L to the minus 35 power times hl. Pressure distribution behind two-dimensional steps is measured at Mach number of 2.25 and Reynolds numbers between 0.35 to 5x Re sub L to the minus 35 power times hl. Good agreement is found between the analytical calculations and the experimental data as well as other published experimental data. Pressure distribution behind axially-symmetric backward facing steps is measured at Mach number 2.25 and Reynolds numbers of 3 to 10 to the 6th power. It is shown that the flow around the axially-symmetric step is similar to that about a free base and is the correlated using the parameter Re sub L to the minus 15 power times hl. Comparison is presented also with published data and good agreement is found. Author