Flows in the Annular Region when an Underexpanded Nozzle is Exhausted into a Stepped Launch Tube.

reportActive / Technical Report | Accession Number: ADA088581 | Open PDF

Abstract:

An experimental program has been conducted in which unheated air was exhausted through a stationary rocket nozzle into a constant-area-tube launcher modified with a constrictive ring. The constrictive ring simulates a constraint which could be a permanent or temporary part of the launch tube. For the first phase of the test program the static wall-pressure distribution, upstream and downstream of the ring, and the mass flow-rates in the annular gap were measured. Given an underexpanded nozzle, a correlation between the generation blow-by, or reverse flow in the annular gap, and the position of the nozzle exit-plane relative to the front face of the ring was developed. The flow phenomena present in the launcher for different nozzle positions has also been investigated. For the second phase of the test program the static pressure distribution on the surface of the rocket and the mass flow-rates in the annular gap were measured. The differential pressure distributions on the rocket were related to the mass flow-rate in the annular gap with increasing blow-by flow, and with increasing ejector flow. Author

Author(s):
Bouslog, Stanley A. ; Bertin, John J.
Author Organization(s):
TEXAS UNIV AT AUSTIN DEPT OF AEROSPACE ENGINEERING AND ENGINEERING MECHANICS
Descriptive Note:
Final rept. 1 Mar-30 Sep 79,
Pagination:
0108

Security Markings

DOCUMENT & CONTEXTUAL SUMMARY

Distribution:
Approved For Public Release

RECORD

Collection: TR
Identifying Numbers
Report Number(s):
80001, DRSMI/RL-CR-80-4
Contract/Grant Number(s):
DAAK40-79-C-0021
Monitor Series:
CR-80-4, AD-E950 021
 Subject Terms
Joint Capability Areas:
JCA_3.2_Engagement; JCA_3_Force Application; JCA_3.2.1_Kinetic Means; JCA_1.2_Force Preparation; JCA_1_Force Support; JCA_4.6_Engineering; JCA_1.2.3_Educating; JCA_5_Command and Control; JCA_1.2.5_Lessons Learned
Modernization Areas:
Fully Networked C3
Communities of Interest:
Weapons Technologies
Descriptor(s):
*FLOW FIELDS, *LAUNCH TUBES, *NOZZLE GAS FLOW, *EXHAUST NOZZLES, *ROCKET NOZZLES, *ROCKET LAUNCHERS, *ROCKET EXHAUST, *EXHAUST GASES, *SECONDARY FLOW, INTERACTIONS, SHOCK WAVES, MASS FLOW, FLOW RATE, EXPANSION, SUBSONIC FLOW, SUPERSONIC FLOW, RINGS, EXHAUST PLUMES, STATIC PRESSURE, PRESSURE DISTRIBUTION, ROCKETS, GAS FLOW, CONICAL NOZZLES, FREE FLIGHT MODELS, FREE FLIGHT TRAJECTORIES, IMPINGEMENT, CONSTRICTIONS, CONVERGENT DIVERGENT NOZZLES
Field(s)/Group(s):
Rockets, Fluid Mechanics
Keyword(s):
Free flight rockets, Reverse flow, Blow by flow, Mallaunch
Report Date:
1980 Mar 01