Search found 144 matches

by Rocket Man
Fri Aug 19, 2016 1:06 am
Forum: Valved pulsejet forum
Topic: Pulse Jet Compression
Replies: 6
Views: 1603

Re: Pulse Jet Compression

1. Pulse jets are not efficient. 2. Temperature is from about 1400 F on propane, gas, or kerosene but can be higher on other fuels. 3. Db = LOUD over 150 Db. 4. Low Hz. the German V1 was about 40 Hz. My Argus PJ-20 it about 200 Hz. You can determine the Hz here, http://hyperphysics.phy-astr.gsu.edu/...
by Rocket Man
Sun Jan 17, 2016 1:42 am
Forum: Valved pulsejet forum
Topic: WITH OR WIHOUT VALVES, WHAT IS MORE EFFICIENT
Replies: 26
Views: 13909

Re: WITH OR WIHOUT VALVES, WHAT IS MORE EFFICIENT

It is not true that a pulse jet will not go faster than Mach .6. America research in the 1950s on the JP-Loon project pulse jets reached 950 mph. Not much of the original research data is still available. See if you can find research data on the JP-Loon. The German V1 had a very complicated fuel sys...
by Rocket Man
Sun May 31, 2015 12:10 am
Forum: Valved pulsejet forum
Topic: Frequency of a spring = reed valve
Replies: 3
Views: 2142

Re: Frequency of a spring = reed valve

I have been doing research on valved pulse jet engines since 1970. You are correct most PJ engines will run no matter what the valve frequency is but the engines run best if the valves are closed when the engine fires. If the engine fires with the valves open the increased combustion chamber pressur...
by Rocket Man
Mon Feb 16, 2015 1:38 am
Forum: Valved pulsejet forum
Topic: New to the Pulse Jet forum- HK Red Head fuel consumption
Replies: 5
Views: 1961

Re: New to the Pulse Jet forum- HK Red Head fuel consumption

The very best fuel tank is a hospital IV bag. Put in the amount of fuel you want then remove all the bubbles. 1 micro small bubble will make the engine stop running. Put the fuel tank up front near the fuel intake about 1" below the fuel intake. The guys at Days of Speed & Thrunder use a battery fue...
by Rocket Man
Fri Feb 13, 2015 2:26 am
Forum: Valved pulsejet forum
Topic: New to the Pulse Jet forum- HK Red Head fuel consumption
Replies: 5
Views: 1961

Re: New to the Pulse Jet forum- HK Red Head fuel consumption

I have an empty 15 oz pork and bean can for a fuel tank. My engine runs about 90 seconds on gas. If you put an OS45 model airplane needle valve in the fuel line of the pulse jet you can throttle it down to any things from 25% throttle to 100% throttle. The engine starts very easy on low throttle. Yo...
by Rocket Man
Mon Dec 29, 2014 9:55 pm
Forum: Valved pulsejet forum
Topic: 20 lb Thrust Pulse Jet Engine KIts
Replies: 0
Views: 1945

20 lb Thrust Pulse Jet Engine KIts

I am having some 20 lb thrust Pulse Jet Engines engine kits laser cut. Is anyone interested? This is a one time thing. The more I buy the cheaper they are. Auto Cad work is $300 minimum. Set up and labor is $95 per hour with 1 hour minium. Not sure what the price of metal is yet. I am having a few k...
by Rocket Man
Wed Dec 17, 2014 10:31 pm
Forum: Rocket forum
Topic: 120 lbs thrust rocket engine went 3.5 miles
Replies: 6
Views: 4897

Re: 120 lbs thrust rocket engine went 3.5 miles

Another thing that is extremely unstable is Ammonium Nitrate mixed with laundry bleach. This forms an explosive gas that is unstable at or above 95 degrees F, unstable in direct sun light too. In the summer after the sun goes down and the temperature drops put the gas in balloons. This is a funny pr...
by Rocket Man
Sun Nov 02, 2014 3:50 am
Forum: Valveless pulsejet forum
Topic: how to set up a liquid fuled engine
Replies: 16
Views: 4586

Re: how to set up a liquid fuled engine

What works best for me is a duel fuel system. Start the engine on propane, then turn on the liquid fuel.
by Rocket Man
Tue Oct 28, 2014 5:27 am
Forum: Valveless pulsejet forum
Topic: Blast Compression Intake proposed design
Replies: 78
Views: 30969

Re: Blast Compression Intake proposed design

Ogge I hope you can make it work. How do you plan to deal with an unstable pulse jet frequency? I designed a pulse jet engine that ran at 200 Hz. Tests showed it ran at 200 Hz plus and minus 4 to 5 Hz and some time as much as plus or minus 14 Hz. The engine sucks in the amount of air fuel it needs o...
by Rocket Man
Tue Oct 28, 2014 3:24 am
Forum: Valveless pulsejet forum
Topic: M500 build log
Replies: 161
Views: 40310

Re: M500 build log

Does it run?

I would like to see a video.
by Rocket Man
Mon Oct 06, 2014 9:23 pm
Forum: Valved pulsejet forum
Topic: 20 lb Thrust Twin Engines
Replies: 2
Views: 1615

Re: 20 lb Thrust Twin Engines

That's awesome Rocket. How do you regulate between 2 psi and 10 psi fuel pressure? In the work shop I use an adjustable regulator to get the psi I need but on the bike I use full tank pressure and volume is adjusted with a 500 psi industrial needle valve. http://i67.photobucket.com/albums/h292/mike...
by Rocket Man
Mon Oct 06, 2014 3:32 pm
Forum: Valved pulsejet forum
Topic: 20 lb Thrust Twin Engines
Replies: 2
Views: 1615

20 lb Thrust Twin Engines

The first engine that I built has pedal valves, the second engine has Argus valves. Both engines have fuel injection like the German V1. Both engines start easy at 20% throttle on about 2 psi propane and run at full thrust at 10 psi fuel pressure. Both engines run good on gasoline, gas/diesel fuel m...
by Rocket Man
Tue Sep 02, 2014 2:17 pm
Forum: Valved pulsejet forum
Topic: Warm engine hard to start
Replies: 13
Views: 3503

Re: Warm engine hard to start

I see the problem. The reed valve retainer diameter is too small.
by Rocket Man
Thu Aug 21, 2014 5:32 am
Forum: Valved pulsejet forum
Topic: Rotary valves do not work.
Replies: 4
Views: 1987

Rotary valves do not work.

Test have proven that rotary valves do not work. The #1 problem is, NO pulse jet engine runs at an EXACT same frequency all the time. Test have proven the pulse frequency of the engine varies by as much as 14 Hz. The test engine runs at about 200 Hz, the frequency goes up and down 5 to 7 Hz all the ...
by Rocket Man
Fri Sep 06, 2013 9:34 pm
Forum: Valved pulsejet forum
Topic: Material Thickness
Replies: 3
Views: 1115

Re: Material Thickness

I use muffler pipe and EMT electrical conduit for building engines. I'm not sure of the thickness maybe .060". It takes some practice to weld it with my a stick welder using my old 1970s Lincoln Welder.