SECONDARY COMBUSTION OF PENTABORANE-HYDRAZINE EXHAUST IN AIR
Abstract
The C* (characteristic velocity) performance of the air-augmentation stage was determined in two flight simulation regimes. In the sea level/Mach 2. 5 regime (200 psia chamber pressure/800 F air-temperature), the c* performance efficiencies were 96-99% of theoretical at air-to-propellant ratios of 8:1, 16:1, and 50:1. Chemical analysis indicated complete combustion of all primary exhaust products, including boron nitride and elemental boron. In the 40,000 ft/Mach 4.0 regime (50 psia chamber pressure/1500 F air-temperature), the c* performance was 91-92% of theoretical at air-to-propellant ratios of 8:1 and 16:1. Chemical analysis indicated high boron nitride combustion efficiency but very low elemental boron combustion efficiency. Low chamber pressure and low residence time were concluded to be major contributing factors to the low elemental boron combustion efficiency and reduced c* performance efficiency. A high water concentration in the secondary chamber, resulting from secondary hydrogen combustion, appears to contribute significantly to the high combustion efficiency of the boron and boron nitride. A model describing the secondary combustion process has been developed. The model reflects the importance of water vapor and high chamber pressure in promoting high combustion efficiency and high performance efficiency of boron-containing propellants.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1968
- Accession Number
- AD0392716
Entities
People
- Robert C. Adrian
- Robert E. Yates
- Sanders D. Rosenberg
Organizations
- Aerojet Rocketdyne Holdings