|
Title: Ramjet rocket build log Post by: Husein on March 21, 2011, 10:22:24 PM Major next level rocketry coming up, fabrication timeline depends on availability of :Rs:. If someone needs the math behind this please pm me. Tips and techniques welcome
Title: Re: Ramjet rocket build log Post by: Husein on March 21, 2011, 10:23:20 PM oops sorry inlet geometry given here
Title: Re: Ramjet rocket build log Post by: rcpilotacro on March 21, 2011, 10:29:22 PM i can only tell you one thing, ram jet is a little tricky to start compared to a pulse jet, Ram Pressure recovery has to be carefully planned, 1. cater for intake losses, 2. plan two to three obliques before a normal shock wave to avoid very high entropy, if need any help send me some details i can check it / run the sim for you. there is a easier way of managing obliques, i can share it with you, for the forum though it will be too much. all the best
Title: Re: Ramjet rocket build log Post by: Husein on March 21, 2011, 11:37:58 PM The ramjet is inefficient below mach 2, frankly it isnt even a ramjet below that speeds, my main work is done on CFD, I make a model to put it on display at my college final project submissions. The inlet is designed on oswatitch principle and has ramps of 9.5deg, 10.5, 11.5 for max pressure recovery and a normal wave terminating just before the combustion chamber, although the hurdle I am facing is not enough computation power
Title: Re: Ramjet rocket build log Post by: izmile on March 22, 2011, 03:54:10 AM Are you building an operational ramjet or just a static display?
Title: Re: Ramjet rocket build log Post by: Husein on March 22, 2011, 07:01:00 PM A static display, would definitely want to be part of a team making a operational ramjet, given enough capital and research facility, but in those circumstances I'd rather be batman :giggle:
Title: Re: Ramjet rocket build log Post by: Husein on April 05, 2011, 11:17:18 PM Here it is Gentlemen, after days of arduous work, I present to you KAMEHAMEHA, as you can see there is still some finishing work left, please help me choose a color scheme for this (inlet/body/fins). Thank you and comments most welcome
Title: Re: Ramjet rocket build log Post by: ujjwaana on April 06, 2011, 12:04:32 AM Wow!! It looks like 'Bhramos'. Keep it away from the sight of the Authorities.
Title: Re: Ramjet rocket build log Post by: iamahuman on April 06, 2011, 07:49:08 AM DBZ fan eh? ;)
Nice work. Title: Re: Ramjet rocket build log Post by: carenaman on May 14, 2011, 10:54:57 PM Very good Job buddy
Title: Re: Ramjet rocket build log Post by: nchandra on May 14, 2011, 11:53:38 PM wow,
you said "although the hurdle I am facing is not enough computation power " can you specify what kind of computation u are/werelooking at ?? Title: Re: Ramjet rocket build log Post by: Husein on May 15, 2011, 12:13:43 AM While doing computational fluid dynamic post processing, if I would give no. of pathlines more than a certain no. the whole simulation would stop and i would have to restart it, also due to lack of a good graphic card the results were not very clear, vortices missing in a few places they were expected and shocks would not get captured, although this project is done now and I have a new comp with good capabilities(i-3, 4gb ram, 1 gb dedicated graphics). Thank You
Title: Re: Ramjet rocket build log Post by: rcpilotacro on May 15, 2011, 01:41:01 PM is it a variable geometry intake ? if yes, it requires some work ? for Fixed geometry/ variable on ground, looks ok (Except the Cone Tip), upto 1.4 mach Pitot type would have sufficed, Single Normal Shockwave will have a lot of Wave Drag, this intake will have a normal shock and may not have obliques.
Just thoughts based on images Title: Re: Ramjet rocket build log Post by: Husein on May 15, 2011, 02:08:46 PM No sir, this isnt variable geometry intake. i should have looked into the simple pitot type inlet in more detail. Also I might have overlooked the fact of excess wave drag due to single normal shock, but this inlet does create obliques from the ramps, which has been shown by the pic, the pic is not mine but from a research paper by Dr. Akbarzadeh, which states the efficiency of the use of multiple ramps in ramjet inlets.
|