Search found 33 matches

by fogus
Tue Mar 03, 2009 7:01 pm
Forum: Hybrid Cannons
Topic: HYBRID FUELING 101
Replies: 106
Views: 278045

It almost seems like a mistake. He might have meant to say, "precise to within 0.1 psi". I'd ask. No, the meter is accurate to 1 PSI. For digital displays "precision" simply describes the resolution of the display. +/- 0.2 or 0.1 PSI for this digital display. There is no relationship between "accur...
by fogus
Tue Mar 03, 2009 5:48 pm
Forum: Hybrid Cannons
Topic: HYBRID FUELING 101
Replies: 106
Views: 278045

It almost seems like a mistake. He might have meant to say, "precise to within 0.1 psi".

I'd ask.
by fogus
Mon Nov 17, 2008 9:38 pm
Forum: Combustion Cannons
Topic: can someone crunch the numbers for me?
Replies: 9
Views: 1966

No, it was because I had a calculus exam the next day and all I could think of was, practise practise practise.

What do I do with the spudbux? Can I order food? I'm not hungry now, but I will be later. I know this from previous experience.
by fogus
Sat Nov 15, 2008 2:41 pm
Forum: Combustion Cannons
Topic: can someone crunch the numbers for me?
Replies: 9
Views: 1966

I was reviewing for a calculus midterm that day.
by fogus
Thu Nov 13, 2008 3:01 pm
Forum: General How-To & Discussion
Topic: Request for PVC Burst Pressures Test Results
Replies: 18
Views: 2918

As this has come up, I'd like to take the opportunity to reiterate my request - any takers? :D I'll second that request. I might just carry out that experiment using an HPA tank. Any suggestions on how to connect a steel pipe to the end caps. I think I would use steel pipe for the pressure hose. Pl...
by fogus
Wed Nov 12, 2008 11:10 pm
Forum: Hybrid Cannons
Topic: Ignition past valve / Ignition by fuze
Replies: 8
Views: 2101

I played around with gasEQ. Does someone mind checking to see if the following would be reasonable for an insane 12X accident (maybe I should stay away from this stuff): [Conditions] 3 Adiabatic T and composition at const V [Reactants] ------------ No.moles ------------ Mole fraction H2 ------------...
by fogus
Wed Nov 12, 2008 10:39 pm
Forum: General How-To & Discussion
Topic: Request for PVC Burst Pressures Test Results
Replies: 18
Views: 2918

In my opinion the fatal blow to pvc hybrids came when noname's sch80 one exploded at 2x. There is no way I'd use pvc after such a low pressure failure, even if his pipe did have a defect. Wow, I guess this is only useful data for normal combustion cannons and pneumatic cannons. I guess it's possibl...
by fogus
Wed Nov 12, 2008 10:35 pm
Forum: Hybrid Cannons
Topic: Hybrid Hydrogen Fuel Canisters
Replies: 10
Views: 2147

Thanks guys, Lentamentalisk , what kind of calculations can be used to find the spontaneous ignition point of hydrogen/oxygen? Off to do some more reading on electrolysis (please don't think I just randomly throw out ideas I have not done any reading on)... rp181 , does sodium hydroxide totally prev...
by fogus
Wed Nov 12, 2008 12:43 am
Forum: General How-To & Discussion
Topic: Request for PVC Burst Pressures Test Results
Replies: 18
Views: 2918

Request for PVC Burst Pressures Test Results

Hello All, This is a request for anyone to post their experiences with PVC at high pressures, whether it burst or not. I am most interested in finding the limit of schedule 40, pressure rated PVC in sizes from 1" to 4". I believe this data will be helpful to anyone building a hybrid or high pressure...
by fogus
Wed Nov 12, 2008 12:32 am
Forum: Hybrid Cannons
Topic: Ignition past valve / Ignition by fuze
Replies: 8
Views: 2101

Thanks, Ragnarok.

Would that 70-100PSI rule of thumb apply to oxygen/hydrogen mixes as well?
by fogus
Wed Nov 12, 2008 12:28 am
Forum: Hybrid Cannons
Topic: Hybrid Hydrogen Fuel Canisters
Replies: 10
Views: 2147

You will also get spontaneous detonations of your fuel canisters, because in order to fill your much larger chamber to 12x, you will need to have the fuel canister at 120x at the least. Do not attempt this. No no, I wouldn't do that. I want to use a 6-12X charge mix to fill a 1X (atmospheric) chamb...
by fogus
Tue Nov 11, 2008 7:38 pm
Forum: Hybrid Cannons
Topic: HYBRID FUELING 101
Replies: 106
Views: 278045

uhmmm yes you did.... 1x mix is a 'proper' mix of air and propane at atmospheric pressure 2x mix is a mix of air&propane at 2atm and so on Yes, that's why I called it a nominal 1X mix. It is 0.62 PSI above a true 1X mix, but it makes it easier to do the calculations. A my starting nominal 1X actual...
by fogus
Tue Nov 11, 2008 6:42 pm
Forum: Hybrid Cannons
Topic: Ignition past valve / Ignition by fuze
Replies: 8
Views: 2101

What's wrong with any of the numerous methods that use electrical energy to ignite the mixture? Nothing, I'm just having fun. We'll see if I ever get something like this off the ground. DIY told me that a 2X propane/air mix will get me a maximum of 250 PSI for a short time and then the pressure wou...
by fogus
Tue Nov 11, 2008 6:35 pm
Forum: Hybrid Cannons
Topic: Hybrid Hydrogen Fuel Canisters
Replies: 10
Views: 2147

Hybrid Hydrogen Fuel Canisters

In my quest for an ever simpler means of construction, I thought it might be fun to try hydrogen/oxygen, created from the electrolysis of water. I would be using this mix to fill my charges (same charge as seen here: http://www.spudfiles.com/forums/files/fueling_system_1_162.png except I would not b...
by fogus
Tue Nov 11, 2008 6:18 pm
Forum: Hybrid Cannons
Topic: HYBRID FUELING 101
Replies: 106
Views: 278045

OK, I believe I have a recipe for filling a hybrid combustion tank in my head. It is: 1. Decide on what --X (compression ratio) you want to end up with. 2. Assuming your chamber is filled with 14.7PSIa of air: 3. Raise the pressure of the chamber to 14.7 + 0.62 = 15.32 PSIa using propane. (I will co...