u/BloodyAlice-

Hello everyone! I am an aerospace engineering student with an IT background and I am developing an experimental rocket engine with which I want to make various experiments changing propellant composition. (Like different OFs).

From what I can grasp, changing your propellant will affect your nozzle design.

Now, I know you can use numerical methods, but from what I can grasp of Rocket Propulsion Elements, ninth edition chapter 3, I get that you could define chamber to throat (so, both diameters) without changing much and you could easily get your exit area to throat area relation using a tool like CEA.

Now, this leaves me with some questions:

1. How do you define Throat area? I am calculating it from a static chamber area which is constrained by the design, using a chamber to throat area ratio of 4.5. A bit higher than the 3.5 from the 3-2 table. Is this correct? Should I take other things into account?

https://preview.redd.it/67060g6f500h1.png?width=912&format=png&auto=webp&s=681f19ac97e46cefd1d12a7fe18a5841ae9fd242

2. From what I understand a conical throat could be completely "straight", with no curves, is this correct?

3. I am using formulas to get values like cone length and other things, is this correct or I better get into numeric methods straight away?

4. How viable is to automate this process? Are there any tools that do it? In case there aren't, why? Is it plain impossible, too hard or the complex of the project doesn't outweigh the benefits?

Thanks for reading and sorry if I missed something.

(pun intended)

Hello guys! Sorry if this is a weird thing to ask but I am pretty new, I started playing with a friend like 2 weeks ago.

I am playing Zerg rn and I've been using PiG's build order from 2023. Although I found some pitfulls is pretty entertaining. The thing is, from what I understand builds go up to minute 5 or 6, less than ten.

This brings me to two questions:

1. How do you create a build?

2. How do you properly branch? I've been trying to play reactively and checking counters (I play with liquipedia on my second monitor, I already learnt a few tho). From what I saw it's kind of predetermined 'cause of tech but what's the thought process there?