ronbros3

WELL how far along are you, any pix???????

damic

Not a clever idea, the modern diesel pumps are high pressure pump +2000bar and can be driven of a multi-v belt. You'll need the FD's ignition timer to know when he's on the first and second rotor to inject and detonate the diesel mixture.

It's not so hard todo the conversion, but it's hard to control the ignition.

youngfc

iTrader: (1)

Still on paper for the most part. Its just hard to stick money into something you havent even gotten approved, but I figured out an injection system that Iv been reworking so it fits on the 13b just so I could get the basics figured out as far as timing it (not as easy as you'd think). sorry guys, but Im not the best with electronics so Im going to keep it simple for now and go with a mechanical injection system. no camera but Im trying to borrow one of the school's so I can. im planing on my first attempt at making the housings and rotors at the end of feb. if that fails at being cost efficient then ill modify some rc nitro rotary engines to run it but if I go that route... well can you say 3 rotor maybe even 4 rotor lol.

greyseason

This is a awesome project to do for school, but your telling us you are going to make your own housings and rotors? the money you will fork out will be insane, especially for a school project. Check out this thread, and youll see the work involved in making just the rotors. Good luck though man
https://www.rx7club.com/old-school-other-rotary-63/tegheim-home-made-4-rotor-wolvo-project-892879/

youngfc

iTrader: (1)

@ greyseason thank you! but I dont plan on making it fancy just run for now. housings I was thinking about making sleeves that just press in so I can replace them and if I royaly f*!# up I can fix it easier. rotors will be very heavy not hard to machine just simple and solid. later in life when I have well... more money and time ill go back and redo some parts like the rotors and the injection system. I just dont have the time or money to make something optimal but it is version1 lol. gotta start somewhere.
thanks. oliver

greyseason

oliver, you said you were making the Eshaft out of titanium.. that alone must have been a fortune

ronbros3

more info,, there is noway to make mechanical injection work at 15000rpm, absolutly noway!!


maybe this will stir some creative knowledge?

KansasCityREPU

iTrader: (9)

I say make a proof of concept before sinking all this money/time. There has to be a way to take a 12A/13B and prove it will work before taking on a complete engine made by hand.

goonie

Go for it man! Don't let skeptics slow you down on an amazing idea!

youngfc

iTrader: (1)

Thanks guys well for a 13b or any of them Id still need to open the keg and mod or make new rotors (and thats hoping the stock seals can cope with a diesel) which I just cant afford now, but a simple workin 250cc 2 rotor is much much cheaper. Im making this e-shaft out of some 4140 same as oem (making it myself and I got the metal around so $0 invested). ti for the second go around after I see if its even worth it along with a much better injection system. Sorry I dont think I was very clear through this, but first go around I just want it to run, and maybe rev to 7k; then on the next one after I learn what and how I can make it better ill do all the nice things and build something sweet lol.
thanks for the support, oliver

youngfc

iTrader: (1)

should start on hard parts sometime this month (birthdays on the 21st and my buddy said he was gonna have my e-shaft done then) so should be posting pics then.

youngfc

iTrader: (1)

I dont know about any of you guys, but all I can think of when I think of this is throwing it in a light little bike frame and watchin it fly lol... then hang a t25 off the side of it, and keep adding boost tell she melts or blows a seal

youngfc

iTrader: (1)

Gettin ready to put the shaft on the lathe, and was wondering if anyone knew how to change the CR by changing the Eccentricity of the shaft? It just dawned upon me that the 13b shaft I was using for measurements wont let me have the CR I need for an autoignition engine. also would changing the Eccentricity mean I have to change the shape of the housings?

..........................what have I gotten myself into here lol
Thanks oliver.

madbouncy

I have a spreadsheet where you can put in the eccentricity, R' and it'll give you the outline it makes. It also makes a triangle that would represent the tips of the rotor along the housing at BDC and TDC. I was too lazy to complete the equation but it has it in there what it would take to reach different compression ratios as far as displacement goes. You'll just have to put in your own radius until it matches up from there you can see if that radius is possible or not. Kind of cumbersome but I just made it and I'm too busy right now to have it auto solve for the radius and then graph that on there as well.

Just PM me and I can e-mail it to you and I'll work on it quick to see if I can get it to show the radius on there and maybe see if I can get it to solve for the radius as well.

Also, the amount of time you have per stroke is 270 degrees instead of 180 as with a piston motor. So you actually only have 1.5 times longer to inject fuel and have it auto-ignite. Which means you revving the rotary to 15000 rpm is the same as a piston going to 10000 rpm and that's generally a tad bit higher than diesels generally run. You'll be limited to the amount of time it takes for the diesel to actually ignite and since your chamber is constantly moving, you would almost need multiple injectors so you can put the fuel in early enough at high rpm but not soo early at low rpm that you fire way before TDC.

youngfc

iTrader: (1)

THANK YOU!!! YOU DON'T KNOW HOW MUCH THAT JUST MADE MY DAY. Thats kinda funny because I just thought of that a week ago; 3 stages is what I was planning.I knew about the 270 vs 180 intake ect, and the 1/3 rotor speed. the diesel part im not to worried about just yet. More the making something, and getting all the mechanical kinks out. Then see how that goes, and thats because I never made a rotary engine from scratch before. have any of you lol? I have made a little vtwin, and just getting it to turn smooth by hand was a chore let alone get it runing.
but from the sounds of what Madbouncy's saying all that should be worked out fairly simply.
Thanks Oliver

DickGetty

And if a man should ever travel, say, faster than a horse can run, he will pass out.

The speed alone will take his breath away!

youngfc

iTrader: (1)

thanks dickgetty
now i need a mentor for this thing and was wondering who would volunteer? I don't know yet if they have to be local or can be away (only had class 3 days so far and only got to 1 of them) ill post more when i get it, thanks.
and last but not least can anyone give me a crash course on draftsight 2d or solidworks 3d? it would be much appreciated. i have been playing with it for the past week but im not tech-friendly lol.
Thanks Oliver

youngfc

iTrader: (1)

Alright update still working on the 250cc twin rotor, but just so I can graduate on time, and pass the class lol ( low on funds needed to meet the dead line lol). So I decided to go ahead and save up and buy a OS .30 nitro rotary engine, and rework it to work diesel.
math says with 18.5:1 CR I can get it to be more then enough to run, but with 16.3:1 being at the lowest of where id like to be.
I haven't gotten a definitive number for what it comes with, but I got 7.6:1 as the most common answer, can anyone confirm this? If it is then it will be tricky, but if its 8.0:1 it shouldn't be that bad. Either way for not having side seals that's not bad to start off with. I haven't really had time to see how much theoretical CR it could have which I think a Mazda based seal system would bring it up to at least 13:1. any thoughts?

Thanks Oliver, wish me luck guys this will be the third night im staying up all night, and the next day to get all this done in time, still work and go to school (never wanted to get suspended so bad lol).

youngfc

iTrader: (1)

So now its a 4.9 cc im going for lol.

13BT_RX3

John Deere's Score Rotary ran on Diesel and other fuels. Here's a link to some details:
http://www.auto-engine-parts.net/rota_text_1986_A4.pdf
Here's an excerpt (page 2 & 3):
This dual nozzle stratified combustion system has lived up to its expectations. It has successfully demonstrated its ability to run on gasoline,methanol, diesel fuel, and jet fuel without any engine adjustments.

damic

Damn that's a insane engine 1300Nm @ 1200rpm :o

damic

Any update?

patman

iTrader: (3)

FYI, there have been several diesel rotary development projects in the past, and there are some going on currently (I am working on one right now). None have made it to production that I know of, but many of them were/are very promising.

A couple things you need to look into:

1) read "Rotary Engine" by Yamamoto. This is the 'bible' of the wankel, and will answer many of the questions you have posted in this thread.

2) research 'stratified charge' rotary engines, and understand why this combustion style makes the diesel rotary potentially competitive with piston engines.

3) you might want to consider partnering up with a company that has these components on the shelf to complete your thesis. My company is pretty tight on security and I dont see them being interested, but look up bargerltd.com, they own all of the John Deere intellectual property (they also have an excellent RE history page on their site). There are a couple others as well, but I am not sure how many would be interested.

fidelity101

iTrader: (11)

You won't get any gas mileage in a diesel, you will get fuel mileage.

ar design

What is the plan for apex seals?