Programme Element: ARTES 5.1
Reference nr.: 12.1TT.45
Planned Tender Issue: quarter 2, 2013
(*) Priority 2 - A request for initiation has been received
Objective: Assess implementation of concept, specify system architecture in conjunction with ESA and breadboard very high temperature resistojet.
Targeted Improvements: Using a xenon VHTR would give:
- Big improvements in specific impulse over cold gas propulsion systems (+ 100%),
- Large propellant mass savings (- 50%).
- Commonality with existing EP subsystems.
- At spacecraft system level chemical propulsion (CP) systems for attitude control & EWSK replaced with xenon VHTRs to give better, lower cost solutions.
- Spacecraft ground AIV activities eased by removing CP systems.
Existing resistojet technologies are limited to relatively modest temperatures (< 1000?C), which effectively limits the performance of these devices. Materials and technologies exist in other industries for heating gas flow to very high temperature (>2000?C). At these temperatures dramatic improvements in cold gas system specific impulse (SI) performance may be realised for a wide spectrum of applications. An SI in the region of 100s is predicted for xenon, as opposed to <50s for existing resistojet technologies.
Very high temperature resistojet (VHTR) technology is conceptual at this stage but could be based on materials & manufacturing processes that are increasingly widely used. For example heaters able to operate at > 2000?C, based on high temperature materials are readily available in the vacuum technology domain. Critically the nature of the materials is such that they exhibit extremely high temperature capabilities whilst having exactly the same coefficients of thermal expansion.
From the perspective of GEO Satcoms already employing Xe EP technology the availability of VHTR technology raises the possibility of replacing currently used small chemical thrusters with Xe resistojets, reducing overall spacecraft system complexity, costs & streamlining ground AIV activities.
Task 1- Development of requirement specification of resistojet system in collaboration with ESA, including definition of system architectures & sharing of functions with existing EP systems & technology
Task 2 - Investigation and development of the materials and processes needed to produce the VHTR.
Task 3 - Design of a breadboard VHTR.
Task 4 - MAIT of a breadboard VHTR.
(*) Priority 2 activities will only be initiated on the explicit request of at least one delegation.