STUDY OF HEAT TRANSFER CHARACTERISTICS OF HOT-GAS IGNITERS.
Abstract
Solid propellant rocket motors are frequently ignited by hot-gas sources such as smaller burning solid propellant charges or pyrotechnic grains which exhaust their products of combustion into the motor grain port through convergent or convergent-divergent nozzles located in the head end or aft end of the motor. The results of an experimental program to develop correlations for predicting when and where such hot-gas ignition occurs for conocyl and star grain motor ports are discussed based on a preignition transient convective heat transfer model. The hot-gas source was nitrogen supplied to thin stainless-steel-walled test sections at pressures from 595 to 628 psia and temperatures from 649 to 989 F. A variety of geometrical parameters were studied including igniter nozzle location, exhaust nozzle port area-to-throat area, simulated motor port diameter, included star ray angle for star sections, cone angle and cone spacing for conocyl test sections, and igniter nozzle type, i.e., axial supersonic, axial sonic, and three-port canted. The results are correlated with reference to established relationships for turbulent flow heat transfer in pipes. Significant differences in heat transfer characteristics between head-end and aft-end configurations in addition to significant differences between the star and conocyl test sections were observed. Predictions from the model test results were confirmed during the actual solid propellant motor testing phase. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1967
- Accession Number
- AD0821548
Entities
People
- J. A. Wrubel
- L. W. Carlson