ASCENT Thruster Pre-heat Optimization

Subtopic Problem Statement/Description: Traditional Advanced Spacecraft Energetic Non-Toxic (ASCENT) based propulsion systems require catalyst bed pre-heat temperatures 400 C prior to the introduction of propellant. For small spacecraft (CubeSats) this is performed with close coupled resistive heaters mounted to the thruster. The power requirements for such thrusters are manageable with duty-cycled warmup modes / peak-power-limited power architectures [1]. Now that the feasibility of ASCENT has been demonstrated successfully, the industry is moving towards larger and longer life thrusters [2, 3]. The larger thrusters require more power than the current SOA (100 mN class thrust) which leads to additional complications for thermal management and pre-heat times/power needs. NASA is seeking heater technologies that enable reliable catalyst-bed to preheat for ASCENT-based thrusters up to approximately 25 N while reducing peak electrical power demand, total preheat energy, and warmup time and maintaining adequate thermal uniformity. ASCENT thrusters require catalyst-bed preheat temperatures of 400 C before propellant injection; current 100 mN-class systems achieve this with closely coupled resistive heaters that small spacecraft can generally support using duty-cycled warmup modes and peak-power-limited power architectures. As ASCENT technology scales to larger thrusters (nominally in the 5 N and 22 25 N class), heater power demand, thermal management, and preheat duration become significant constraints on spacecraft power systems and mission design. This subtopic therefore invites solutions such as optimized resistive heater designs (including packaging, mounting, insulation/thermal breaks, and control strategies) as well as alternative heater concepts that can provide the required 400 C preheat for larger ASCENT thrusters and can be adapted to other thrust levels.