Patent ID: 9279503
Filing Date: 2016-03-08
CPC Classification: F02K,F16K,F23C,F23R

Claim Text:
1. A constant volume combustion chamber comprising: an inlet configured to receive a propellant and an outlet comprising a conically shaped nozzle throat and a nozzle outlet configured to allow combustion products to exit the constant volume combustion chamber; a pintle head having a longitudinal axis and comprising a conical sealing portion configured to contact the conically shaped nozzle throat; actuation means mechanically coupled to the pintle head and configured for moving said pintle head into and out of contact with the conically shaped nozzle throat; a thermocouple configured to measure temperature in the constant volume combustion chamber; and a pressure transducer configured to measure pressure in the constant volume combustion chamber wherein: the conically shaped nozzle throat comprises an inner throat seat surface configured to form a pressure tight seal when contacted with the conical sealing portion of the pintle head; the conically shaped nozzle throat and conical sealing portion of the pintle head have diameters that taper from an internal volume of the constant volume combustion chamber toward the nozzle outlet with a taper angle of between 30° and 7°; the conical sealing portion of the pintle head comprises a sealing surface configured to seal against the inner throat seat surface to seal the constant volume combustion chamber; the actuation means configured to alternately move the pintle head so as to seal or open the constant volume combustion chamber; and the roughness of the sealing surface of the pintle head and/or the inner throat seat surface is from 16 microinches to 64 microinches.