Search found 1743 matches
- Fri Jul 14, 2017 2:19 pm
- Forum: Off topic forum
- Topic: youtube
- Replies: 1512
- Views: 550569
Re: youtube
Good find, I may have to try one of those.
- Fri Jul 14, 2017 2:17 pm
- Forum: Jet Vehicles, All Types
- Topic: Jam Jar Car Fun
- Replies: 22
- Views: 25901
- Fri Jul 14, 2017 2:16 pm
- Forum: Tools and Construction
- Topic: TIG Welding
- Replies: 1
- Views: 4583
Re: TIG Welding
Here is a calculator: https://www.millerwelds.com/resources/weld-setting-calculators/tig-welding-calculator If you put the type of metal and thickness in it should give a pretty close place to start. Anecdotally: You want to start with steel, (make sure to start with clean metal) make a puddle on th...
- Fri Jul 14, 2017 2:02 pm
- Forum: Valveless pulsejet forum
- Topic: Cant start pulse jet
- Replies: 6
- Views: 9435
Re: Cant start pulse jet
Bangs are a good thing, and it can take over half a minute of fire to heat the tail up to running temperature. I don't think it's a matter of doing right or wrong. What we see is that there are sets of dimensions that lend themselves to resonant combustion. Size, shape and length of the resonant cha...
- Thu Jul 13, 2017 9:24 pm
- Forum: Jet Vehicles, All Types
- Topic: Jam Jar Car Fun
- Replies: 22
- Views: 25901
Re: Jam Jar Car Fun
Maddox does it again:
https://www.youtube.com/watch?v=lktyx9HHesQ
https://www.youtube.com/watch?v=lktyx9HHesQ
- Thu Jul 13, 2017 9:18 pm
- Forum: Valveless pulsejet forum
- Topic: Cant start pulse jet
- Replies: 6
- Views: 9435
Re: Cant start pulse jet
Looks like the tail is a bit short. It might be helpful to look at the topic in the Valveless section called 'PyroJoes Recipe for Beginners'. I put that up to help show what dimensions are likely to work, and to help out folks new to the pulse jet experience.
As always, happy combustion!
As always, happy combustion!
- Thu Jun 30, 2016 10:10 pm
- Forum: Valveless pulsejet forum
- Topic: PyroJoes Recipe for Beginners
- Replies: 209
- Views: 1825713
Re: PyroJoes Recipe for Beginners
Sorry for the late reply. It should look similar to this drawing. Thanks, and let us know how it goes
- Thu Jun 30, 2016 9:35 pm
- Forum: Valveless pulsejet forum
- Topic: Lovely video...
- Replies: 5
- Views: 8558
Re: Lovely video...
Awesome camera work catching that. Thanks tufty.
- Fri Oct 17, 2014 7:48 pm
- Forum: Valveless pulsejet forum
- Topic: how to set up a liquid fuled engine
- Replies: 16
- Views: 26545
Re: how to set up a liquid fuled engine
Probably the first thing to do is to understand that valveless pulse jets are not like regular mechanical piston engines. There is no mechanical piston to crush the fuel air together. There is no intake valve that shields the intake from the positive pressure from the combustion cycle. The factors I...
- Fri Oct 17, 2014 4:42 pm
- Forum: Tools and Construction
- Topic: Odd Metal jars
- Replies: 554
- Views: 1963879
Re: Odd Metal jars
Example of an inertial pump
In this case the movement of the pump creates the change in velocity.
In valveless pulse jets I would offer that the process is driven by the pressure fluctuations created from combustion (along with the effects of aerodynamic valving).
In this case the movement of the pump creates the change in velocity.
In valveless pulse jets I would offer that the process is driven by the pressure fluctuations created from combustion (along with the effects of aerodynamic valving).
- Fri Oct 17, 2014 4:18 pm
- Forum: Valveless pulsejet forum
- Topic: PyroJoes Recipe for Beginners
- Replies: 209
- Views: 1825713
Re: PyroJoes Recipe for Beginners
Yes, I have worked with shallow cones in many configurations. My work typically has revealed the need to maintain the Helmholtz properties of the CC as a chamber and the -inertial pumping- characteristics of a pipe for the tail. But I would recommend anyone to test it and come to their own reasoning.
- Thu Oct 16, 2014 1:11 pm
- Forum: Off topic forum
- Topic: youtube
- Replies: 1512
- Views: 550569
Re: youtube
Since I use a lot of galvanized pipe I see the yellow stuff often. sometimes it turns into a powder/dust like coating that can be wiped off. Sometimes it forms little dropplets of liquid metal that eventually evaporate. If the metal has been pickled in a certain way the underlying steel has a really...
- Wed Oct 15, 2014 6:50 pm
- Forum: Valveless pulsejet forum
- Topic: PyroJoes Recipe for Beginners
- Replies: 209
- Views: 1825713
Re: PyroJoes Recipe for Beginners
Just to be clear, does tail expansion increase the efficiency of the engine? -From the concepts I have read, a tail expansion helps when the engine is run static. (sitting still) -When the engine is moving at a fast speed, the expansion is less needed. -It also helps the pressure in the combustion c...
- Mon Oct 06, 2014 8:59 pm
- Forum: Valved pulsejet forum
- Topic: 20 lb Thrust Twin Engines
- Replies: 2
- Views: 7405
Re: 20 lb Thrust Twin Engines
That's awesome Rocket. How do you regulate between 2 psi and 10 psi fuel pressure?
- Thu Oct 02, 2014 9:54 pm
- Forum: Valveless pulsejet forum
- Topic: how to set up a liquid fuled engine
- Replies: 16
- Views: 26545
Re: how to set up a liquid fuled engine
It takes considerable knowledge to switch from propane to petrol liquids in valveless pulse jets.