| The constant volume combustion thermodynamic cycle, or Humphrey Cycle, if made practical in a jet engine, can provide enormous benefits over the traditional jet engine cycle, the Brayton Cycle, which is a constant pressure cycle. These advantages include increased thermal efficiency, lower specific fuel consumption, and higher specific impulse. Other just as important benefits inherent in a constant volume device include simplicity of design, the ability to miniaturize the device because of the simplicity, low cost, damage tolerance, expendability, and a high thrust-to-weight ratio. This device has the potential to provide extremely high thrust in an austere, economical package.;All of these attributes, when proven feasible, have the ability to provide a propulsion source for military and civilian applications alike, including applications in miniaturized unmanned aerial vehicles (UAVs). The purpose of this study is to computationally model and understand the physics of a possible constant volume combustion jet engine, including the combustion and fluid mechanics of such a device. Specifically, the investigation will include studying different engine geometries, valve designs and timing, various air inlet and fuel mixing schemes, operating frequencies, nozzle designs, along with the effects of a convective air stream when a supporting vehicle is in flight at various airspeeds. This study will seek to maximize thrust and minimize fuel consumption, and thus develop a jet engine with many possible future applications. |
