An HTS Module for Magnetic Combustion Control in a Lab-Scale Hybrid Rocket Engine

Abstract

Magnetohydrodynamic control of diffusive flames can provide a contactless method for altering combustion in hybrid rocket engines. The presence of a magnetic field modifies conditions within the thermal boundary layer and provides an opportunity for active control of fuel release. However, the realization of the process requires the application of substantial magnetic fields, beyond the capability of copper electromagnets. This work presents a feasibility study of an HTS magnet designed for a lab-scale technology demonstration. The presented magnetohydrodynamic combustion model shows that a magnetic field in the range of 1 T is required to enhance the conditions in the combustion chamber. The realization of cooling to sustain the superconducting state is assumed to be achieved through the utilization of the existing cryogenic environment needed for the liquid oxygen in combustion. The numerical analysis shows that the required magnetic field can be delivered with a mid-sized racetrack coil magnet made of two double pancake coils operating at 65 K. The coil arrangement is shown to be able to withstand the heat generated by the combustion of a 10 s burn. For the lab-scale application, a ferromagnetic core will be used to reduce the amount of superconducting tape required, while retaining a suitable magnetic field. The analysis is concluded with the scaling studies for an HTS coil without an iron core, which shows that a magnetic field of up to 2 T can be achieved.