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Post by britishrocket on Jun 20, 2012 10:08:09 GMT -5
Hi,
Not to worry. So not only have you heard about TU Delft, you are at TU Delft! I first became aware of Steven Engelens DEIMOS project when the report on it appeared in the Journal of the British Interplanetary Society. I have been fortunate enough to correspond with him a couple of times in the last few years.
I am sorry to hear about your leaky valves. I take it you are still working with gaseous propellants? Congratulations by the way on inheriting such a fantastic project.
Anders...I totally understand about your difficulties in resuming your rocket engine work. I moved house before Christmas and there seems to be a never ending list of tasks to do. I am now making decent progress with my workshop though!
Best Wishes,
Carl.
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Post by Johansson on Jun 20, 2012 13:09:38 GMT -5
Anders, too bad about the expensive pressure regulators, I guess we are lucky we can borrow them for free at our university. Heating up the N2O is also an option to increase the pressure in the tank. The team working on a hybrid engine at our university do it all the time. Anyway, as long as you can pressurize the methanol to decent pressure, the thrust shouldn't suffer from it that much. The mass flow is related to the square root of the pressure difference, so if you would only have half the pressure difference between tank and chamber of what you initially wanted, you will still have 70% of your mass flow and thrust. (sqrt(0.5)=0.7) I am hoping to get in touch with someone who is interested in these things who can give me a good price on a regulator, if not I will try to borrow/lend one for the initial test runs. Using CO2 to pressurise the methanol tank will give me similar pressure in both tanks throughout the temp range, that will most likely be the way to go if I don´t find a regulator soon. Heating N2O tanks beyond room temperature is a big no-no for me, I don´t want to get anywhere near the critical temp with friends and spectators standing nearby... |
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Post by Johansson on Jun 20, 2012 13:17:20 GMT -5
Anders...I totally understand about your difficulties in resuming your rocket engine work. I moved house before Christmas and there seems to be a never ending list of tasks to do. I am now making decent progress with my workshop though! Best Wishes, Carl. Then we understand each other.  I cannot allow myself to have fun in the workshop while the house needs painting, the garden needs cleaning up etc., it is first when I have spent a couple of hours and half a bucket of sweat on the boring things that I can allow me to get some work done on the turbine bike and rocket engine. When the autumn arrives and the snow start falling I will have lots of more workshop time available.  |
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Post by britishrocket on Jun 22, 2012 8:11:57 GMT -5
Hi Anders, Regarding pressure regulators, I have been looking at the following company:- www.pressure-tech.comThey are based here in the UK and they manufacture a variety of regulators. I am not too sure of the pricing, but I expect it to be relatively expensive. I think that this will have to be borne however. I expect to have to spend as much on the test set up as I will on the manufacture of the engine. That said, it is a cost which will only have to be met once. Best Wishes, Carl. |
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Post by Johansson on Jun 22, 2012 16:02:13 GMT -5
Thanks for the link, the "low cost" regulator looks interesting indeed. If only they would specify what "low flow" means, 1mm3/s or 1m3/s? My main problem is that this project, no matter how interesting and rewarding it may be, is only a distraction from my main and most likely life long committing turbine bike build. Every cent I spend on the rocket engine is a cent I cannot spend on the bike so I will have to cut every corner available to row this boat ashore as we say here in Sweden. |
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jdw
Member
Joined: January 2012
Posts: 41
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Post by jdw on Jun 27, 2012 19:29:30 GMT -5
Hey guys excellent work on all fronts. I found a useful link you might be interested in aeroconsystems.com Cheers, Justin |
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Post by Johansson on Jun 28, 2012 0:30:52 GMT -5
Wow, thanks a lot for that link!
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Post by Johansson on Jun 28, 2012 16:08:54 GMT -5
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jdw
Member
Joined: January 2012
Posts: 41
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Post by jdw on Jun 28, 2012 17:54:51 GMT -5
Happy the link helped I've come across other useful links i'll check and see if i have any others that might be able to yield fruitful results.
Salute,
Justin
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Post by Johansson on Jun 29, 2012 15:51:27 GMT -5
Please do, thanks again for this one. I payed 1/20 of what a new regulator would cost me over the counter here in Sweden so I am as happy as a 15 year old boy hidden in the womans sauna. |
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Post by Johansson on Jul 5, 2012 0:15:56 GMT -5
The regulator should arrive any day now, it is currently in custom clearance here in Sweden.  |
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Post by Johansson on Jul 10, 2012 10:52:25 GMT -5
I got the high pressure regulator today!  Capable of 400 bar and regulates between 0-140 bar so it is perfect for this and other applications where I need a regulated pressure, I will have hydraulic hoses made from the nitrogen bottle to the regulator and for the scuba tank as well so I can use it to regulate air pressure as well.  Finally I have everything I need to test the rocket engine, I have talked with the local car tuning company and they will fill the N2O rocket tank despite the lack of a burst plate. I will make sure they only fill it half full since I will only need a couple of seconds of stable running right now. First I will pressure test the entire system with water and air pressure of course to make sure there is no leaks and that the tanks can take the pressure. Cheers! /Anders |
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Post by Johansson on Jul 13, 2012 16:15:13 GMT -5
Since the gas turbine bike build has come to a temporary halt while waiting for news about the gearbox I´ve ordered I have time to get some work done on the bipropellant rocket engine again! There is really not that much left to do before it is ready for a test run, I have to make the coupling between the regulator and nitrogen bottle and do some plumbing. After that I will sacrifice my hydraulic jack and make a water pressurisation pump out of it so I can test the feed system up to 200bar (full nitrogen pressure in case the regulator fails), then a water flow test will follow to check for leaks and confirm that the regulator can hold a steady pressure at the feed rates needed. Before the test can be made a concrete test bed will have to be cast on my lawn, if I place it closest to the ant nest my feancee shouldn´t complain overly much... Cheers! /Anders |
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Post by turbochris on Jul 13, 2012 19:30:00 GMT -5
Have a pressure washer handy? they're great for pressure testing things.... even hydroforming.
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jdw
Member
Joined: January 2012
Posts: 41
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Post by jdw on Jul 13, 2012 23:06:45 GMT -5
Turbochris, could you please explain a little more about hydroforming with a pressure washer? This sounds very interesting!! Maybe another thread?? And have you had anymore developments with the WHY-2k bike?
Thanks,
Justin
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