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Re: A brand-new ignition method

Posted: Fri Nov 11, 2022 9:57 am
by jackssmirkingrevenge
Looking good!

I assume that in the interest of safety you've made sure that all the pipes and fittings are rated for the expected pressures after ignition ;)

I note that while the paper you shared concluded that "When the volume of the initiation end is larger than that of the booster end, you can get more pressure" but in this case you've elected to go with a smaller volume for ignition.

If I understood correctly, you will first pressurize the main chamber (50x), this will keep a check valve between the chambers shut, then you can pressurize the ignition chamber (10x). After ignition, the pressure in the ignition chamber will rise enough to overcome the force on the check valve, and the hot gasses will flow into the main chamber and ignite the 50x mixture.

What is the failure pressure of your burst disk?
What target do you want me to place? It will launch a 10.5mm steel ball.
I very strongly recommend being behind cover when you try it, in the event of DDT you have the potential for a pipe bomb and high velocity steel fragments are not a healthy prospect.

Some sort of metal plate is usually the most satisfying target personally but be extremely careful that you cannot be hit by a ricochet.

I will always cite this example of when an 8mm steel ball from one of my pneumatic project ricocheted and left a clean hole in my bedroom window, that could easily have been my head :o

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Re: A brand-new ignition method

Posted: Fri Nov 11, 2022 10:44 am
by hectmarr
You can use my mother-in-law as a target... JOKE! :twisted: What I'm dying to know is if the whole concept will work well. In my opinion YES! she will do it.

Re: A brand-new ignition method

Posted: Fri Nov 11, 2022 9:59 pm
by yyt
jackssmirkingrevenge wrote:
Fri Nov 11, 2022 9:57 am
Looking good!

I assume that in the interest of safety you've made sure that all the pipes and fittings are rated for the expected pressures after ignition ;)

I note that while the paper you shared concluded that "When the volume of the initiation end is larger than that of the booster end, you can get more pressure" but in this case you've elected to go with a smaller volume for ignition.

If I understood correctly, you will first pressurize the main chamber (50x), this will keep a check valve between the chambers shut, then you can pressurize the ignition chamber (10x). After ignition, the pressure in the ignition chamber will rise enough to overcome the force on the check valve, and the hot gasses will flow into the main chamber and ignite the 50x mixture.

What is the failure pressure of your burst disk?
What target do you want me to place? It will launch a 10.5mm steel ball.
I very strongly recommend being behind cover when you try it, in the event of DDT you have the potential for a pipe bomb and high velocity steel fragments are not a healthy prospect.

Some sort of metal plate is usually the most satisfying target personally but be extremely careful that you cannot be hit by a ricochet.

I will always cite this example of when an 8mm steel ball from one of my pneumatic project ricocheted and left a clean hole in my bedroom window, that could easily have been my head :o

Image
Yes, for unknown high-power explosions, a remote control igniter is essential. Your understanding is completely correct. I will use a circular iron piece with a thickness of 0.3mm and a diameter of 25mm as bursting discs. They are cheap, with 200 pieces for only $3, and can just be placed on the washer above the cam lock. To be honest, I don't know how much pressure it will burst, but so far, it is safe at least at 5mpa. Honestly, the reason why I didn't use the big room to ignite the small room is because I suspect that my small room can't withstand the explosion pressure!

Re: A brand-new ignition method

Posted: Fri Nov 11, 2022 10:00 pm
by yyt
hectmarr wrote:
Fri Nov 11, 2022 10:44 am
You can use my mother-in-law as a target... JOKE! :twisted: What I'm dying to know is if the whole concept will work well. In my opinion YES! she will do it.
I agree