Search found 1241 matches
- Tue Jun 29, 2010 9:41 pm
- Forum: Off topic forum
- Topic: suspect your electric (in tank) fuel pump
- Replies: 41
- Views: 27553
Re: suspect your electric (in tank) fuel pump
Noticed the wifes S-10 is skipping a few beats at low acceleration, will check the ignition system with a timing light tonight, if it tests clean it is most likely the fuel pump. Mileage has also been decreasing with the engine putting off a rich smell from the exhaust, another sign that points to ...
- Wed May 12, 2010 8:12 pm
- Forum: Tools and Construction
- Topic: I tried to cast aluminum last week
- Replies: 8
- Views: 10448
Re: I tried to cast aluminum last week
Besides the things you´ve pointed out I should have guessed that the teflon coating in the pie shape would burn and cause cavities, but it was only a primary test and did indeed inspire us to make a more serious attempt later with an oil burning forge and better quality aluminum Be careful At 680°F...
- Sun Apr 25, 2010 9:09 pm
- Forum: Valveless pulsejet forum
- Topic: Acoustic length
- Replies: 13
- Views: 12469
Re: Acoustic length
I'm no acoustic engineer, but I think the accurate calculation of acoustic length for a pulsejet must be a pretty complex business, because of the wildly changing conditions in the pipe during even a single cycle. Larry: You've nailed it pretty good there. Dwayne: If you're capable of asking questi...
- Mon Apr 19, 2010 4:37 pm
- Forum: Tools and Construction
- Topic: UFLOW and Helmholtz
- Replies: 7
- Views: 8461
Re: UFLOW and Helmholtz
This chart is from essential reading thread, it plots combustion time to diameter: I'm glad you've found that chart and have observed its importance. You'll find that it constrains how short a pulsejet can be relative to its diameter. The length of the pulsejet is the primary driver of frequency an...
- Thu Mar 25, 2010 6:43 pm
- Forum: Off topic forum
- Topic: suspect your electric (in tank) fuel pump
- Replies: 41
- Views: 27553
Re: suspect your electric (in tank) fuel pump
Hi Forrest Intermittent problems seem to love you and naturally collect around you ;-) Does your Mum's car have a diagnostic port? Viv Here's a few tips from a car guy ( I did service writing and managing in the late '90's): 1. All cars sold in the US starting in '96 are OBD II spec; among other th...
- Fri Feb 19, 2010 5:54 pm
- Forum: Valveless pulsejet forum
- Topic: Kraken
- Replies: 44
- Views: 33127
Re: Kraken
Started construction on the Kraken. Two (ported) 6.75"dia. CCs pusing a 4.25"dia main tailpipe. Looks like a fun and challenging project. Good luck with it! Maybe I can pass along some tips and save you some grief, with the following: 1. You really need to flare the intakes and both ends of the int...
- Sat Feb 13, 2010 7:24 pm
- Forum: Valveless pulsejet forum
- Topic: More free plans: 40 pound Chinese
- Replies: 192
- Views: 824039
Re: More free plans: 40 pound Thermojet
Hi Metiz On another topic your weld beads look much improved ;-) good work Viv Not totally sure I agree here. I'm not trying to stir up trouble--but it looks as though your welds are not penetrating the base metal by very much. For max strength they SHOULD. Have you tried making a weld sample and t...
- Fri Feb 12, 2010 10:40 pm
- Forum: Valveless pulsejet forum
- Topic: Calculating top speed on ice...
- Replies: 575
- Views: 296292
Re: Calculating top speed on ice...
If the intake length is so tied up with the tailpipe length, will thermal expansion during running not mess up this fine balance? I believe the engine must be designed for its operating temps. Metal expansion is one important reason these engines don't start right up from cold; another is the need ...
- Wed Feb 10, 2010 10:41 pm
- Forum: Valveless pulsejet forum
- Topic: Would this work? Project: BenJet XL 0.1
- Replies: 35
- Views: 27725
Re: Would this work? Project: BenJet XL 0.1
Hi and welcome to the forum! No offence but you just made the "Beginner Mistake 1A" by starting to figure out a groundbreaking new and completely untried engine without any previous experience. I´ve seen it on many different forums and I´ve made it myself once or twice before I started reading up o...
- Sat Jan 16, 2010 6:12 pm
- Forum: Valveless pulsejet forum
- Topic: Calculating top speed on ice...
- Replies: 575
- Views: 296292
Re: Calculating top speed on ice...
HI again: I just had a thought: It would be pretty simple to modify that head-end plate into a sealed reservoir, which would absorb considerable heat from the combustion chamber. This would provide quite a lot of the necessary heat input for vaporization. A couple turns around the outside on the way...
- Sat Jan 16, 2010 6:04 pm
- Forum: Valveless pulsejet forum
- Topic: Calculating top speed on ice...
- Replies: 575
- Views: 296292
Re: Calculating top speed on ice...
You have a point there, do you know if the SNECMA engines were direct injected or used vapourisors? Pretty sure they were direct. Of course there would still be ways to raise the temp of the fuel along the way--right? This would reduce the need for heat extracted from the interior of the engine. I ...
- Sat Jan 16, 2010 4:08 pm
- Forum: Valveless pulsejet forum
- Topic: Calculating top speed on ice...
- Replies: 575
- Views: 296292
Re: Calculating top speed on ice...
Thanks! Actually I am not sure what fuel I will run her on, diesel would be the safest fuel but I will also try gasoline and E85 just to find out which one is the best. It's worth noting here that both the German Argus pulsejet used on the V1 flying bomb and the SNECMA efforts in valveless engines,...
- Thu Jan 07, 2010 1:13 am
- Forum: Valveless pulsejet forum
- Topic: Varying the thust in a pulsejet
- Replies: 3
- Views: 4972
Re: Varying the thust in a pulsejet
Well, this is fortunate-- I've been working on some fiction stories where valveless pulsejets play a fairly major role, but haven't been able to find out one answer while doing research: Can they be throttled? Is it possible to increase or decrease the thrust of a pulsejet, or are they pretty much ...
- Thu Dec 31, 2009 2:50 am
- Forum: Gas turbine forum
- Topic: Need Plans for Turbo Charger Jet Engine
- Replies: 12
- Views: 10686
Re: Need Plans for Turbo Charger Jet Engine
Did a search for DIYgasturbines found a photo posted there 16 years ago. Only information is him running the engine at different RPMs. Did a search for more information. There is no information to be found. I did search for turbo charger and turbo jet engine all it finds is this forum with all the ...
- Tue Dec 22, 2009 9:38 pm
- Forum: Off topic forum
- Topic: The ElectraFlyer C plug-n-fly electric plane
- Replies: 10
- Views: 8366
Re: The ElectraFlyer C plug-n-fly electric plane
Agreed, far less heat than IC. So 90% efficiency gets you 10% of power going out as heat plus I^2*R, which I neglected to mention. So if you know the resistance of the motor windings, and the amperage, you get X watts out as heat. Faaaascinating. Hi Mike Plus the loss in the motor control power out...