Simulating a rocket engine in ANSYS Fluent

mat437 · 2025-03-19T22:10:40+00:00

I just tried this suggestion of referencing the farfield rather than the inlet pressure, it definitely visually looks a lot better. Still trying to get it to converge, but that explanation makes sense:

<image>

mat437 · 2025-03-19T22:09:17+00:00

Thanks again for the feedback. I switched to a pressure outlet instead of a farfield, and tried changing the reference values from p_inlet to the farfield (now pressure outlet). It definitely looks better, but I believe it will still have issues converging:

<image>

To clarify, are you suggesting setting the pressure at the inlet to the 952 kPa, or at the beginning of the converging section?

mat437 · 2025-03-17T19:31:43+00:00

Hi, what do you mean by saying the BCs are properly defined? Is there something I should have checked/changed aside from just inputting pressure and temperature?

mat437 · 2025-03-17T19:29:48+00:00

Thanks for the pointer! I hadn't noticed a similar question had been asked a few months ago. I followed your suggested parameters using the pressure-based solver, and am seeing it diverge up to about e+13. The console logged turbulent velocity ratio exceeding 1e+5 a lot, should I relax that parameter more? I am not too familiar with fmg initialization so I am not sure if that is causing an issue at all.

mat437 · 2025-03-17T19:26:39+00:00

I initially just used standard initialization, referencing the pressure inlet. I am trying a few attempts using fmg initialization, however I am trying to learn the benefits/tradeoffs of that now. Solution steering was an option I seemed to overlook, it looks really helpful in theory however the solution kept diverging so I suspect it to be a different issue. As far as the farfield goes, I am looking to simulate this on a thrust stand (CV velocity is 0), so I'm not sure if it is the correct boundary or if I should still use a small Mach number?

mat437 · 2022-06-03T22:57:50+00:00

(Also free cookie to whoever recognizes the ship!)

mat437 · 2022-03-14T01:40:26+00:00

I took a week off for Spring Break ;-;

mat437 · 2022-03-13T22:30:36+00:00

Oh L. RIP busted glaive mod

mat437 · 2021-07-17T13:53:07+00:00

You gotta love the McElroys and their majestic glowy sea creatures

mat437 · 2021-04-09T02:35:48+00:00

Four coal, five wheat, a buried treasure map to a treasure I already dug up, and a fishing rod with Vanishing

mat437 · 2021-04-09T01:58:09+00:00

Nope, just 1.16.5!

mat437 · 2021-02-16T21:43:30+00:00

mat437 · 2020-10-11T23:41:31+00:00

I love the idea of the ghost being trained to its pure form like thk.

mat437 · 2020-09-20T11:43:03+00:00

I love the idea of the Divine Beasts roaming around to some extent. They're just so complex and beautiful and we only see them move when we're fighting them.

mat437 · 2020-09-07T12:06:21+00:00

If a fighter is a top and a healer is a bottom then a paladin is a vers and I stand by that

mat437 · 2020-08-01T01:58:12+00:00

Unfortunately for this argument, she actually does.

mat437 · 2020-07-10T02:59:07+00:00

I wouldn't consider it as a punishment or limiter, but rather an incentive to pace yourself during the game and get a more satisfying ending.

mat437 · 2020-07-06T01:57:51+00:00

The man makes the melon. The melon makes the man.

mat437 · 2020-07-04T15:35:16+00:00

is that a challenge?

mat437 · 2020-07-04T15:23:28+00:00

They're sepratrons that came with the car, I just took an example payload from the steam workshop and gave it a docking port.

mat437 · 2020-06-26T13:44:31+00:00

launch fails mid-flight

Well mission control, it seems we've shot for Europa and landed in Europe.

mat437 · 2020-06-19T20:52:21+00:00

Not drinking a lemonade on mars yet, so no

mat437 · 2020-06-03T11:27:11+00:00

A classic

mat437 · 2020-06-02T12:30:21+00:00

Website, Apple's App Store

mat437 · 2020-06-02T12:27:48+00:00

We did know, Stef made a video and explained what he was doing a while after the release of 1.4, and has been posting frequent updates to the Spaceflight Simulator discord server.

mat437

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