New Mars Forums

RGClark

Member

From: Philadelphia, PA

Registered: 2006-07-05

Posts: 765

Website

A proposal for hypersonic propulsion.

A key problem with scramjets is that the air stream is moving so fast it's difficult to have enough time to complete combustion.

Then the idea is to use stagnation points where the air is still with respect to the vehicle to collect the oxidizer and to combust with it. Stagnation points are known to exist for reentry vehicles.  They should also be present for caret-shaped waveriders and clam-shell wings.

  The air that collects there can be combusted externally or drawn in and combusted with standard turbojets since the air is still with respect to the vehicle. The external combustion would have the advantage of simplicity but would be less efficient since the combustion products would expand in all directions, not just rearward. The turbojet approach would allow all the exhaust to be directed rearward, but would be heavier.

If this works we may also be able to use this for reentry at Mars. At hypersonic speed, the great heat generated will dissociate the CO2. We may then be able to combust the O2 with onboard propellant, saving the need to bring the oxidizer from Earth.

Bob Clark

Last edited by RGClark (2023-05-15 09:10:25)

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Old Space rule of acquisition (with a nod to Star Trek - the Next Generation):

      “Anything worth doing is worth doing for a billion dollars.”

tahanson43206

Moderator

Registered: 2018-04-27

Posts: 19,408

Re: A proposal for hypersonic propulsion.

For RGClark re new topic...

Best wishes for success with this interesting and inspiring new topic.

The services of a student with access to a full featured CFD program would be helpful.

It is also possible your proposal might interest a professional who works for a company able to afford a full-featured CFD program.

One detail that might pop out of the analysis is the temperature of molecules at any stagnation points that might be created.

If the CFD program can be persuaded to iterate over a range of configurations, it might be able to find the configuration of the structure that achieves the best possible performance.

At the very least, this idea ** should ** be worthy of a Master's degree.

A quick search revealed that Autodesk now offers CFD Analysis Software.  The vendor I've been following is Flow3D, which appears to be a major player in the space.

Google found something called "Flowcal" which apparently has a following.

Please continue developing the potential of this topic.

Note: If you want to bring peers into discussion here, I am happy to provide membership.  We have thousands of ID's recovered from spammers.  What I am NOT interested in are persons who join and then never contribute.  If you want to build a project team, this would be a good place to do it.  I am confident your Admin team would be supportive, and I am equally confident Mars Society is supporting this forum.

(th)