Explosion pressures
Explosion pressures
(OP)
I am looking for some good reference material for calculating explosion forces of a gas, i.e. hydrogen. Obviously pressure will be a function of the containment vessel size,which can be calc'd with a known force. For a given mass of explosive material, is there a formula to calculate force after ignition.





RE: Explosion pressures
I, personally, don't think that simply mass is sufficient to determine blast pressure. One key parameter is burn rate of the material. The same quantity of diesel and gasoline have radically different combustion behavior.
TTFN
RE: Explosion pressures
explodes with a click-like sound in an open cup but gives
a painfully loud explosion if the cup is closed with a
soap bubble.
<nbucska@pcperipherals.com>
RE: Explosion pressures
- a model of the reactions involved
- the heat of combustion and thermodinamical model
- some model of the gas phase behaviour.
In the simplest case :
H2 + 1/2 O2 --> H2O
From the mass balance you see that there is a decrease in volumen (from 1 1/2 to 1 ), so the reaction would lead to a decrease of pressure if there is no heat involved !!
But, with the heat balance , you know that there is an important increase in temperature (due to combustion) an then, in adiabatic conditions, you can calculate the adiabatic temperature.
Finally, with a model of gas phase, the simplest would be ideal gas: P = n . R. T / V, you can estimate the final pressure.
Hope this helps a little
RE: Explosion pressures
Patricia Lougheed
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RE: Explosion pressures
RE: Explosion pressures
Diesel in liquid form is quite tame, but in vapor form with plenty of oxygen, it will combust reasonably well.
Aluminum under most conditions will simply burn, but aluminum powder dispersed with plenty of oxygen as in an FAE, will produce spectacular effects.
TTFN
RE: Explosion pressures
Goodluck!
saxon
RE: Explosion pressures
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