jetmanjoe
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Joined: October 2023
Posts: 64
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Post by jetmanjoe on Dec 18, 2023 6:17:06 GMT -5
Got this great little load cell and panel meter from Aliexpress to measure the thrust on my jet engine test stand. youtube.com/shorts/4EkQC4LSX8U?si=voB3klHG5lMePhYHAll the bits are slowly making there way to me in the mail. Got some time off work in January and hope to make a dent in the build. |
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jetmanjoe
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Joined: October 2023
Posts: 64
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Post by jetmanjoe on Dec 26, 2023 5:05:40 GMT -5
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richardm
Senior Member
Joined: June 2022
Posts: 413
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Post by richardm on Dec 26, 2023 6:53:51 GMT -5
Hi I'm currently working on my own fuel system. It will use diesel
How much pressure are you planning to feed your nozzle with? I also used similar couplers but they were standard 8mm to 8mm shaft couplers from Ali Express. I can say that they're not very forgiving about shaft alignment Make sure to build an accurately aligned pump/ motor mount. the slightest misalignment will translate in increases torque on the motor and a vibrating assembly. To check the alignment I used a watt meter and looked for the lowest reading while running the pump
My system uses a modified domestic oil burner pump I've runned it at 300 psi ( my gauge limit but capable of a lot more)
How are you planning to throttle your engine? I m currently experimenting 3 options: variable speed on the pump motor, variable pressure regulator or a needle valve ..
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jetmanjoe
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Joined: October 2023
Posts: 64
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Post by jetmanjoe on Dec 26, 2023 8:47:08 GMT -5
Hi Richard,
I will type up all the specs tomorrow and talk about how I plan to meter the fuel.
Joe
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richardm
Senior Member
Joined: June 2022
Posts: 413
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Post by richardm on Dec 26, 2023 9:10:00 GMT -5
Great! There's a picture of my fuel pump on my thread about the oil system
Looking forward to discuss some more oaths topic!
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Post by andym on Dec 26, 2023 12:54:25 GMT -5
Hi Richard, I will type up all the specs tomorrow and talk about how I plan to meter the fuel. Joe HI, for the size of turbo you are running, a bosch 044 fuel pump ..... its tried and tested many times on our engines Or as richard has done, a motor and a oil burner pump. What are the seals in the hydraulic pump you are using, looks like a group 2 pump ? if the seasl are not compatable the shaft seal will fail. Controling the rmp of a pump is not how it done, pumps are designed to work at a rpm, make pressure and flow at x rpm..... changing rpm, you are not going to know how the pump is proforming |
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richardm
Senior Member
Joined: June 2022
Posts: 413
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Post by richardm on Dec 26, 2023 14:46:38 GMT -5
Hi Andy and jetmanjoe! What do you both think of my point of view:
My thinking is trying to match the pump volumetric capacity as closely as possible to the needs of the engine. I mean from the volumetric point of view, there's no point in pressurizing much more than needed fuel only to bypass the surplus back to the tank side with a regulator. It only drains the battery faster with might be of some importance on a mobile application. It seems to me that even the smallest hydraulic pumps have more than necessary displacement.
Right now Im feeding my nozzle at 200 psi with 18 watts on 24 volts...
That said, I might be wrong and Im seeking your opinion...
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Post by andym on Dec 26, 2023 16:49:05 GMT -5
Hi Andy and jetmanjoe! What do you both think of my point of view: My thinking is trying to match the pump volumetric capacity as closely as possible to the needs of the engine. I mean from the volumetric point of view, there's no point in pressurizing much more than needed fuel only to bypass the surplus back to the tank side with a regulator. It only drains the battery faster with might be of some importance on a mobile application. It seems to me that even the smallest hydraulic pumps have more than necessary displacement. Right now Im feeding my nozzle at 200 psi with 18 watts on 24 volts... That said, I might be wrong and Im seeking your opinion... Hi Richard..... big beleaver in KISS...... KEEP IT SIMPLE STUPID..... pump, bypass return to tank..... some of the oil burners use a bypass nozzle.. Yes we have limited battery power, but you can spend days/even weeks trying things, to get very little returns. Over my years of building, i have learned, it dont always pay to make this and that, in a chance of saving money, just buy the item yes my oil system is more complex, vesc controler and group one oil pump.... but that is needed to run brushless rc motor, that runs cooler and longer than striaght dc motor and power to make silly amouts of oil pressure 200psi is good, lets you use a smaller nozzle, better / smaller drop let size and inpressive.... but as you know from paying with the oil burner pump, they have relief/bypass |
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jetmanjoe
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Joined: October 2023
Posts: 64
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Post by jetmanjoe on Dec 26, 2023 17:09:00 GMT -5
Ok so after many discussion with John (much appreciated  ) over the last month or so talking fuel systems and other things, this is what I am running and why. My turbo inducer is 118mm and I will be using a single oil burner nozzle. If I was to use even two 044 pumps on 24 volts I would have problems as did Smithy on his Gokart. GT6041 kart jetandturbineowners.proboards.com/thread/568/again-gt6041-powered-green-beast?page=36The great thing about this forum is that we can learn from others  Smithy did some fantastic work by testing the output of the 044 pump with increased voltage to show flow rate and pressure. At the end of it all he upgraded to a pump with higher pressure/flow output. If I used a larger oil nozzle to get the full FLOW required for max RPM then I have would trade off PRESSURE not being high enough at lower rpm giving poor fuel atomization. If I went smaller nozzle to bring PRESSURE up at low RPM then the nozzle FLOW would be choked at high RPM. I don't have time to dig through the calculation right now but might in the future. Gotta go to work soon to pay for this thing  My fuel pump set up will use a DC Motor to drive the fuel pump and a PWM controller for the motor. Again don't have time to post all the calculations. DC motor will spin at (loaded) max RPM 2750 Pump is 1cc per 1 rotation So 2750 RPM x 1cc/ rotation = 2.75 lt per minute for max fuel flow. Probably won't be using all of that, more likely use around 2 lt per minute at 500psi with the nozzle I have. I have a selection of oil nozzles sizes from 12 GPH to 24 GPH at 100 psi. I will be using a pressure transducer to measure fuel pressure and with the panel meter I can set the max fuel pressure to cut off the fuel pump relay momentarily. Also using an in-line hydraulic relief valve on the fuel system only as a precaution, PWM Controllers can fail which would then supply full power to the DC Motor and the pump pressure can reach 6000psi if there is restriction. Even the seller recommends an emergency stop button for the controller just in case. The DC Motor will be controlled with the PWM Controller using a POT dial. The great thing with this PWM controller is I can use a hall sensor Foot pedal to control the PWM in the future on a GoKart. I will also be running some other safety features in my test stand as I will be using this Infront of people at events. Turbo RPM Overspeed protection - cuts fuel pumps momentarily. TOT over temp - cuts fuel pumps completely with manual reset. Low oil pressure protection - cuts fuel pumps with manual reset. Overboost protection - cuts fuel pumps momentarily Turbo Low RPM (idle) afterburner cut out Remote mounted Emergency Stop button cuts master relay for whole system All with gauges and warning lights / alarms. Fuel system over pressure protection both electronically and relief valves. As a side note I will be running x2 044 pumps for the afterburner and x1 044 pump for the Hot Streak but that's another story. This is all I got time for this morning. Dc Motor (my motor is 300w not 350) www.motiondynamics.com.au/united-my1016-350w-24v-dc-motor-with-11-tooth-chain-sprocket.htmlGear pump www.hidraflex.com/en/what-group-1/5375-1l015de10r-roquet-gear-pumpDC PWM Speed Controller with Pot www.motiondynamics.com.au/12v-48v-dc-speed-control-50a-external-case-model.htmlHall Sensor Foot Pedal www.motiondynamics.com.au/high-quality-foot-throttle-hall-effect.htmlPanel Meter www.directautomation.com.au/blog/PROSENSE-Digital-Panel-MeterPressure Transducer 50 bar / 750 psi www.directautomation.com.au/pb1165.htmlHydraulic relief valve. Something like this www.hydraulic.online/Hydraulic-Inline-Pressure-Relief-Valve-150-5000-Psi-3-8-up-to-1-BSPP-Ports-p135197199?gad_source=1&gclid=CjwKCAiA9ourBhAVEiwA3L5RFks6lledoRgfwq9mZvvxn2xcL5CUd5HalVZQ8IjIjA8P9lEDrsSeuhoC2a4QAvD_BwE |
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jetmanjoe
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Joined: October 2023
Posts: 64
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Post by jetmanjoe on Dec 26, 2023 17:15:56 GMT -5
Last note this is for my test stand and not a GoKart. There is a difference in how I would design both.
On my test stand it will have lots more gadgets, 'bells and whistles' then a Gokart with less room. I am building this stand to use for the next decade with other projects in mind.
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jetmanjoe
Junior Member
Joined: October 2023
Posts: 64
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Post by jetmanjoe on Dec 27, 2023 0:22:32 GMT -5
So the price for the completely custom made fuel pump coupling is $11.90 USD and shipping is $32 USD. I have ordered two. They were great to deal with so far. |
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Post by andym on Dec 27, 2023 2:27:15 GMT -5
The fun of building these engines is we can do it how we want.....
I dont see the issue using 044 pump, we ran a single 044 on the twin turbo mini with no issue, just noticed the screen you shared that smithy did, please note.... it was a clone pump, and you can run them at 24 volt all day
The reason I have not used PWM on fuel pump is because as you say thay can fail, pluss as you get plenty RFI from the comp wheel , get you pwm to close and it will be effected
Look forward to seeing your build video
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jetmanjoe
Junior Member
Joined: October 2023
Posts: 64
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Post by jetmanjoe on Dec 27, 2023 3:00:29 GMT -5
And that's the best part about being in this forum, get to hear everyone different technical experiences and have fun building different designs in the process.
I don't claim to know everything, never have and never will. That goes for my trade too, I like working with other mechanics cause you get to learn other peoples tricks.
Really looking forward to what 2024 will bring. Hopefully some high velocity gases
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Post by slittlewing on Dec 27, 2023 4:20:50 GMT -5
Looks good Joe!!
I have used PWM very successfully with both 044 pumps and a larger DC Marco oil pump motor. Works great in both my jetbike and on the kart, for both oil burner nozzles and AB ring. Nice and simple to control with no plumbing return needed and more efficient than needlessly pressurising fuel to then waste the energy passing it back to tank 👍👍
Looking forward to more of the build!
Cheers
Scott
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jetmanjoe
Junior Member
Joined: October 2023
Posts: 64
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Post by jetmanjoe on Dec 27, 2023 4:37:02 GMT -5
Here is a draft of my Control Panel, still need to finalise it once I get the electrical junction box delivered. Size is 400mm x 250mm x 125mm to fit all my gauges and controls into  |
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) over the last month or so talking fuel systems and other things, this is what I am running and why.
Smithy did some fantastic work by testing the output of the 044 pump with increased voltage to show flow rate and pressure. At the end of it all he upgraded to a pump with higher pressure/flow output.
