Recent content by yangshi

Randomly popped in my mind when trying to design microvalves and no idea where to post this... Lip motorboating is when you exhale with your mouth closed, causing your lips to flap like a horse and make a fart sound. My question is not what causes the sound but what causes the lip vibration. Any...

If you have to make that, you could drill a hole in the blade and secure it to handle. Set screw/spring pin in the top bar to keep blade/handle up when not in use.

Just trying to understand how efficient RDE's are thermodynamically based on a 2016 paper from Bulat and Volkov titled "Detonation Jet Engine. Part 1 – Thermodynamic Cycle" and a 2013 paper by Nordeen et. al. titled "Thermodynamic Model of a Rotating Detonation Engine": Based on these papers...

Confused trying to visualize your project. You have a tent with a pipe inside taking dust in and want to figure out how much cfm is through a CV in one portion of the tent? Depends on the how big the pipe is, how big the tent is, etc. Worst case, you'll need to do some basic CFD to get a 3D...

Thanks for the reply. So OK, I'll use a thin steel tube then. And yes, I'm trying to find the flame speed and have a static port set up, but I don't want to expose my pitot tube to the flame.

Since pitot tubes measure total pressure from the flow ramming into the total pressure hole, could I use any thin piece of pipe facing the flow (given that it's smooth on the inside) to measure total pressure? Trying to think of ways not to use my pitot tube to measure the total pressure of a...

Halfway through my thesis on a mach 2 ramjet, and I unfortunately realize that I need 50-72 CFM to test it. The only ACs I have are 2 CFM portable pancakes. Is it possible to run say a 25 CFM AC at 50 CFM for a short period of 10-60 seconds? Is there a quantitative way to find how long the AC...

Nevermind, figured it out. Combustion starts in the "diverging" section.

Doing my undergrad thesis on a ramjet and am confused about scramjets. A ramjet's diffuser slows down supersonic inlet flow to low subsonic to allow combustion. But a scramjet's diffuser first slows the flow down, then speeds it back up in the "diverging" section for supersonic combustion. Why...

What electronics are you using? RPi, Arduino, MicroPython? Not exactly sure what you mean by "combined motion". Assuming this means sensor fusion, here's an example of a 3 axis accelerometer + 2 axis gyro with complementary filter to accurately estimate 3 axis orientation...

Sorry if this is the wrong forum to ask. I have a fine spray application where I need ~140 psi but only .3CFM. I'm trying not to buy a regular air compressor (money wasted on unneeded CFM) and am looking at tire inflators, but very few of them have CFM ratings. Any suggestions?

Not sure what this is exactly, but hover your mouse over the "concentric area" and left click. You will click the outside area of the body but, at the bottom left, there will be a bunch of rectangles. Hover mouse over each rectangle and Ansys will highlight specific internal faces. Left click on...

I believe you are right about ignition; you may look up "fire point".

Thanks for the quick reply. Lots of 304 data but nothing on 303. Though, 303 and 304 properties are fairly close, except for UTS.

I'm not sure about liquid rockets but, for car and airplane engines, ignition increases fuel temperature enough to react with air (oxidizer). If you're using liquid propellants, I'm guessing you don't need continuous ignition since the fuel and oxidizer combust at low temps, unless you're going...