Pressure control in a semi-closed volume upon combustion of solid propellants with an exponent in the combustion law greater than unity

The problem of pressure control in a semi-closed volume by changing the cri tical cross-sectional area of a gas-release channel is considered upon soli d-propellant combustion with the pressure, the combustion rate, and the fre e volume varied over a wide range (not smaller than one order of magnitude) . For a system of automatic pressure control, a control algorithm is chosen and the conditions of partial parametric invariance with respect to the va riable dynamic properties of the object to be controlled are formulated. Th e experimental results obtained upon improvement of the control system for solid rocket propellants whose exponent in the combustion law is greater th an unity are given, The reasons for substantially nonstationary modes of op eration of this system are considered, and a simplified model that approxim ates the phenomena of nonstationary combustion of a solid rocket propellant is proposed. The model is identified and the results of mathematical model ing are given. Recommendations on pressure control in the nonstationary mod es of operation are given.