HTP/diesel rocket, chamber volume, chamber wall thickness

[sebastian_acosta]

Hello, I am new in this forum. I hope I can be as useful as you guys are with your advices and knowledge.

I am designing a htp/diesel rocket.
I have all the results from calculations that i got from a program called ceagui in an exel data sheet. As I progress in the design of my rocket i will update the exel sheet.

My current problem is the following: how i get the combustion chamber volume.

-I got the density on the combustion chamber using the equation of state. Then I just divided the mdot/by the density to get the volume, is something else to be considered.
-another question, what’s the optimum length of the chamber.



- I have a combustion chamber pressure of 100 atm and a density of 10kg/m3, seems low, but is ok.....that gives me a huge combustion chamber still..
check m results...
-----I include a spread sheet to compute the nozzle dimensions.


---------------Chamber wall thickness
The second problem is the wall thickness.
To get it I use the following equation: thickness = chamberPressure(psi)*chamberdiameter(inch)/workingStressOfMaterial*2
-i need the working stress of copper alloys and steel, do you have any info?
i have a value of 8000psi for copper from the page :risacher.com/rocket/eqns.html. I think it is to low….





----------------------Ignition-----------ideas
One of the ignition ideas I have is to cover the chamber with catalyst metal foil.
Another is to add catalyst to the fuel. For this job what catalyst do you think is best?

-a 2 stage combustion chamber: in the first stage the h2o2 is exposed to a catalyst chamber and in the second diesel is added to the h20 and o2.


thanks,

sebastian

[sebastian_acosta]

what i am missing when calculating the combustion chamber volume is considering the "stay time" of the propellants being used. the stay time is the time spent by a molecule in the combustion chamber so there is complete combustion.

i would like to know the value for the stay time of h202 and kerosene at that pressure.

does any of you guys has that info?