THRUST VECTOR CONTROL USING MOVEABLE STRUTS

THRUST VECTOR CONTROL OF SOLID PROPELLANT ROCKET NOZZLES CANBE OBTAINED WITH THE USE OF EITHER FLUID DYNAMIC MEANS OR MECHANICAL MEANS. THE FLUID DYNAMIC TECHNIQUES EMPLOY INJECTION OF GAS OR LIQUID INTO THE EXHAUST NOZZLE THROUGH THE NOZZLE WALL. THE MECHANICAL TECHNIQUES EMPLOY MOVING THE NOZZLE EXHAUST BELL BY GIMBALLING AT THE NOZZLE THROAT OR THE USE OF JET TABS AT THE NOZZLE EXHAUST PLANE. INSERTION OF A SOLID BODY INTO THE EXHAUST NOZZLE CAN HAVE THE SAME EFFECT AS THE FLUID DYNAMIC TECHNIQUE BUT REQUIRES THE USE HIGH TEMPERATURE MATERIALS. AN ALTERNATIVE IS TO EMPLOY A TRANSPIRATION COOLED BODY THAT IS PROJECTED THROUGH THE NOZZLE WALL. THE EFFECTIVENESS OF THIS TECHNIQUE AND THE COOLING REQUIREMENTS FOR THE STRUT CAN BE DETERMINED THROUGH THE USE OF COMPUTATIONAL FLUID DYNAMIC TECHNIQUES AND ANALYTICAL HEAT TRANSFER TECHNIQUES. A PARAMETRIC STUDY WILL BE PERFORMED FOR AN CONICAL INTERNAL SUBSCALE AXISYMMETRIC NOZZLE THAT WILL DETERMINE THRUST VECTOR CONTROL (TVC) EFFECTIVENESS FOR VARIOUS NOZZLE AXIAL LOCATIONS AND STRUT CONFIGURATIONS. POTENTIAL PASSIVE MATERIALS AND ACTIVELY COOLED CONFIGURATIONS WILL BE EVALUATED FOR THE STRUT APPLICATION. CANDIDATE MATERIAL WILL BE TABULATED.