EXPERIMENTAL INVESTIGATION OF THE INFLUENCE OF ALTITUDE AND NOZZLE GEOMETRY ON THE BASE FLOW CHARACTERISTICS OF A FOUR-NOZZLE COLD-FLOW ROCKET MODEL
Abstract
The influence of altitude and nozzle internal geometry on base pressure was determined with a four-nozzle rocket model using 7 different sets of conical nozzles having area ratios ranging from 3 to 11 and nominal exit half angles of 7 and 18 deg. Testing was accomplished without external flow using unheated air to simulate the rocket exhaust gases. In the range of altitudes considered, recirculation of the simulated exhaust gases produced high base pressures in the confined base region between the nozzles, and in a portion of the altitude regime the peak base pressure exhibited a reversal in level which was not predicted by previous studies. Reynolds number variations obtained by varying the rocket chamber pressure level had no significant effects on base pressure over the range of conditions investigated. Near maximum altitude conditions, base pressure was found to vary inversely with base vent area changes accomplished by varying the distance from the model base to the nozzle exit plane. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1961
- Accession Number
- AD0327044
Entities
People
- D.w. Little
- R.j. Matz
Organizations
- Arnold Engineering Development Complex