Preliminary design of a university laboratory hybrid rocket engine

Abstract

This paper gives an overview of the preliminary design of a small hybrid rocket engine (HRE) that is being built in support of propulsion research activities at Ryerson University. The initial design work was undertaken primarily with a paraffin and gaseous oxygen (GOx) propellant combination in mind, but the system is readily adaptable to other propellant combinations for future investigations. When a reusable, non-eroding nozzle is necessary for accurate engine performance measurements, a water-cooled copper design is to be employed. This approach offers the added benefit of allowing the cooling water temperature rise to be measured, and thus the amount of heat being handled by the nozzle can be quantified. The preliminary nozzle design is supported by a steady-state computational fluid dynamics (CFD) analysis of the nozzle flows and associated heat fluxes. The overall engine design is further evaluated by examination of internal ballistic simulation results with respect to such factors as expected performance (chamber pressure, thrust, specific impulse, and total impulse) for a given oxidizer mass flow rate and nozzle throat size.