Development of a Cold Gas Propulsion System for the ... - SSL - MIT
Development of a Cold Gas Propulsion System for the ... - SSL - MIT Development of a Cold Gas Propulsion System for the ... - SSL - MIT
the gains in propellant carrying capacity, and the method of mounting the flight tanks to the vehicle would most likely have to be revised. Other possible upgrades might be identified with more in-depth analysis of the pressure and mass flow characteristics of the CGSE. For instance, it might be worthwhile to use larger-diameter tubing on the low side, even if it had a low working pressure rating preventing the regulator output pressure from being set to maximum, if the larger diameter resulted in less pressure loss on the way to the thruster chamber. More efficient sizes, combinations, and/or configurations of fittings, such as those forming the low side manifold, might also be identified with future trade studies. While there might be some performance gains to be made by upgrading the CGSE, they would likely be relatively small, since cold gas is simply not a particularly efficient form of propulsion. To make any significant improvements, particularly in terms of longer flight times, it would likely be necessary to convert the TALARIS spacecraft emulator propulsion system from cold gas to an energetic propellant. As discussed in section 2.3.2, the most likely candidate for this upgrade would be monopropellant hydrogen peroxide. However, an upgrade of this scale would require a significant investment of time and money, and development would have to proceed extremely carefully, due to the more extensive hazards inherent in working with energetic propellants. Unless a large source of funding could be procured specifically for the development of a hydrogen peroxide propulsion system, it would be prudent to commit resources gradually, carefully assessing the feasibility of ideas before investing large amounts of time and money in system development. For example, the initial team working on the upgrade should be small – possibly only a single person. Development of a hydrogen peroxide propulsion system might proceed in similar fashion to that of the CGSE, by starting with a review of existing technology, developing appropriate requirements, and producing an initial system design. Then, testing of individual components and eventually small subassemblies of the propulsion system could be performed to assess feasibility of the design and also to gain expertise in working with hydrogen peroxide. For this stage, it would be good to identify another program or organization already working with high-concentration hydrogen peroxide or possibly with chemicals of a similar nature, in order to investigate the possibility of taking advantage of their facilities and expertise. If no suitable opportunities were found at MIT or Draper, it could be worthwhile to look into collaboration with another Boston-area university or company, or even any of the military facilities in Massachusetts, such as Hanscom Air Force Base. It might even be possible for a student to apply for summer research fellowships that could allow them to work on hydrogen peroxide thruster 116
development under the supervision of a mentor at another university, a NASA center, or some similar facility even if it were far from the Boston area. However, the idea would be to keep the project and the number of people involved in it as small as possible until a better sense of the feasibility of the design and the challenges associated with implementing it had been developed. If that were achieved, the TALARIS team could then begin to think about expending significant resources on purchasing and storing hydrogen peroxide, identifying and outfitting a location in which to safely test hydrogen peroxide rockets, and training enough team members in hydrogen peroxide safety to allow for operation of the full TALARIS vehicle with its new, more dangerous spacecraft emulator propulsion system. Although converting to a hydrogen peroxide propulsion system would probably result in a significant increase in performance as compared to the CGSE, it is important to consider all the consequences of such a change and how they would affect the overall goals of the TALARIS project. While the hydrogen peroxide system would probably make TALARIS a more capable testbed, with the ability to produce higher thrust levels and to fly for longer periods of time, it might negatively impact its function as a demonstrator, since the increased safety concerns would limit the number of places it could operate and also make it difficult for audiences to observe the vehicle at close range. It is important to consider the relative emphasis of these two roles for the hopper and also to be aware of any other opportunities that might develop as the TALARIS project moves forward, in order to determine the best course of action for future work. 117
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development under <strong>the</strong> supervision <strong>of</strong> a mentor at ano<strong>the</strong>r university, a NASA center, or some similar<br />
facility even if it were far from <strong>the</strong> Boston area. However, <strong>the</strong> idea would be to keep <strong>the</strong> project and <strong>the</strong><br />
number <strong>of</strong> people involved in it as small as possible until a better sense <strong>of</strong> <strong>the</strong> feasibility <strong>of</strong> <strong>the</strong> design<br />
and <strong>the</strong> challenges associated with implementing it had been developed. If that were achieved, <strong>the</strong><br />
TALARIS team could <strong>the</strong>n begin to think about expending significant resources on purchasing and storing<br />
hydrogen peroxide, identifying and outfitting a location in which to safely test hydrogen peroxide<br />
rockets, and training enough team members in hydrogen peroxide safety to allow <strong>for</strong> operation <strong>of</strong> <strong>the</strong><br />
full TALARIS vehicle with its new, more dangerous spacecraft emulator propulsion system.<br />
Although converting to a hydrogen peroxide propulsion system would probably result in a significant<br />
increase in per<strong>for</strong>mance as compared to <strong>the</strong> CGSE, it is important to consider all <strong>the</strong> consequences <strong>of</strong><br />
such a change and how <strong>the</strong>y would affect <strong>the</strong> overall goals <strong>of</strong> <strong>the</strong> TALARIS project. While <strong>the</strong> hydrogen<br />
peroxide system would probably make TALARIS a more capable testbed, with <strong>the</strong> ability to produce<br />
higher thrust levels and to fly <strong>for</strong> longer periods <strong>of</strong> time, it might negatively impact its function as a<br />
demonstrator, since <strong>the</strong> increased safety concerns would limit <strong>the</strong> number <strong>of</strong> places it could operate<br />
and also make it difficult <strong>for</strong> audiences to observe <strong>the</strong> vehicle at close range. It is important to consider<br />
<strong>the</strong> relative emphasis <strong>of</strong> <strong>the</strong>se two roles <strong>for</strong> <strong>the</strong> hopper and also to be aware <strong>of</strong> any o<strong>the</strong>r opportunities<br />
that might develop as <strong>the</strong> TALARIS project moves <strong>for</strong>ward, in order to determine <strong>the</strong> best course <strong>of</strong><br />
action <strong>for</strong> future work.<br />
117
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