A variable flow gas generator is desired to meet present and future requirements for primary missile power supplies variable flow solid propellant gas generators can offer significant improvements in packaging volume when compared with constant flow devices the principle advantage is that the flow rate can be adjusted to match the average gas flow, rather than the peak flow. There are three techniques by which the flow rate cam be modified: accumulator effect, mass addition and flow restriction. The accumulator effect is the result of expansion of pressurized gases in the gas generator volume. The mass addition is based on injection mass, either solid, liquid or gas, into the burning volume. Restricted flow is based on the fact that gas generators will burn at a faster rate at the elevated pressure induced by restricting the exhaust flow. An important part of the task is an analysis of the flow requirements. This would include effective modeling of the various flow control techniques as well as the stability of the flow control mechanisms. Preliminary studies indicate that an approximate 70% reduction in gas generator volume can be achieved by using a demand flow system.
