Mathematics of rocketry?

skybuster said:

Hi everyone!

It wasn't until a while ago until I began to think about the math that is involved in rocketry, but I'm lost on what all is used. I imagine that there's equations for altitude, CP, CG, drift. I was wondering if anyone might know what the equations are and what other type(s) of math and physics is involved with rockets.

Thanks

Click to expand...

Every part of a rocket, both amateur and commercial, can be described by math and physics. The approach everybody here has taken is that of flight mechanics/performance. There are equations that govern structures, propulsion and fluid mechanics, aerodynamics and flight mechanics, electronics, GNC (where applicable), and more. All of these are typically difficult-to-solve partial differential equations that are linearized and simplified (for a narrow-ish range of cases that we may reasonably expect to see, based largely on order of magnitude analysis and operational envelopes) into more familiar equations. It is unrealistic to expect to become an expert in all of the equations that govern rockets, but if there is a specific area of interest, we could certainly clarify. Most performance problems can be solved with algebra, geometry, and introductory calculus, which will yield a pretty good first order solution. The more accurate you need to be, the more complex the mathematics and physics.

rocketguy101 said:

TR-10's "sister" publication, TIR-100 from Centuri is posted here https://rocketguy1010.jimdo.com/ (look on the left side).

Click to expand...

Last page of that document is epic awesome.

Wow talk about putting my knowledge of rocketry into perspective, just when I am starting to gain a bit of confidence I read this thread. Thank the rocket gods for simulation software!

jadebox said:

One of the reasons that I join many others in promoting rocketry as a fun and educational hobby for young kids is that I learned a lot about math and physics long before I took classes that covered those topics because of my interest in rockets. I was having fun and .... oh my ... learning stuff at the same time!

One resource that I relied upon was the collection of Technical Reports from Estes. They mailed me a large package of them after I used rockets in a Science Fair project. They are available online now:

https://www.google.com/search?q=technical+reports+site:estesrockets.com

A problem with them, though, is that some use US customary units (feet, pounds) instead of SI (meters, kilograms, Newtons). SI units make the math much simpler to use and understand.

-- Roger

Click to expand...

Jon Rocket is a knowledgable, adiquite, and reliable source of information. Do not take it lightly.

Late to this thread I have to say I'm surprised that (The Hand Book of Model Rocketry) was not sighted as a good beginning source for the Math and Physics of rocket flight.

during the early 70's BC (Before computer) at least home PC's Both Estes and Centuri published a series of extremely helpful and in depth pamphlets covering the entire range of rocketry math and physics.

Show below are these books: If searching they are still available in library and on-line as well as come up occasionally on e-Bay. Well with the bucks spent.

Something else that should be at least pointed out: All currently available consumer Mod-Roc design and simulation software have major "assumptions" to make the programs easier to build and thereby create a good amount of built-in variance from actual "real world" flight performance. Expressed altitude estimates and even Static Margin and stability of rocket designs ARE impacted by these Assumptions so NO computer program simulation should be though of or EVER taken as absolute or correct.

The ONLY true way to ascertain the flight worthiness of a NEW design is through actual Flight testing which MUST always be done is as NEAR Isolation, (away from People and property) with as FEW range personal as possible.

Micromeister said:

All currently available consumer Mod-Roc design and simulation software have major "assumptions" to make the programs easier to build and thereby create a good amount of built-in variance from actual "real world" flight performance.

Click to expand...

What are the "major assumptions" you are most concerned about?

I mention this because it didn't see it in any of the previous posts, but my favorite source is "Topics in Advanced Model Rocketry". If you have some intro differential equations from high school or college, then it is very easy to follow. https://mitpress.mit.edu/books/topics-advanced-model-rocketry