userscott
Junior Member
Joined: March 2019
Posts: 96
|
Post by userscott on Mar 18, 2019 18:40:57 GMT -5
Thanks for confirming, though I haven't yet researched how to make the evaporator setup.... I was hoping for atomizing but I've realised since that I won't have anywhere near the pressure for that.. so evaporation it is. My design uses stainless steel 1/4 tube into the combustion chamber. I've enclosed a first draft below. Questions/notes: - The blue line was my intended Kerosene spray line. - Red line is intended compressed air inlet line. - Green Tertiary, Amber Secondary, Red Primary. - 5 Primaries to cool the cap down. - Rest of Primaries and Secondaries inline with the Kerosene input. - Am I even close? Cheers Scott
|
|
|
Post by racket on Mar 18, 2019 20:31:51 GMT -5
Hi Scott
The Secondaries need to be displaced further down the flametube away from the Primaries ...............thats why they're called Secondaries , they add air after combustion has taken place
Cheers John
|
|
userscott
Junior Member
Joined: March 2019
Posts: 96
|
Post by userscott on Mar 18, 2019 20:43:44 GMT -5
Hi John, That was my understanding, but I think I got confused by a response you'd made on another persons build thread about merging the primaries and secondaries when running on kero. Should I adjust it to a more conventional layout? I'm struggling to understand the evaporation setup. A thread recommended in another build thread used syringe type injectors which I haven't planned for... Many thanks Scott
|
|
|
Post by racket on Mar 18, 2019 22:07:00 GMT -5
Hi Scott "Merging Primaries and Secondaries "....................I'd need to know the context for that comment as it doesn't sound right, but for a "normal" length flametube with room for all three Zones , we may as well use them . With evaporators/vapourisers the "easiest" way is to silver solder syringe needles into some sort of fuel manifold simply because it saves drilling very small holes and the needle acts as a bit of plumbing to delivery the fuel to where you want it . On my two shaft kart , I used a central fuel delivery tube between the 4 evap entries , with 4 holes drilled into a "square" end on the tube to maintain alignment jetandturbineowners.proboards.com/thread/40/2-shaft-turbine-kart-build?page=2
|
|
userscott
Junior Member
Joined: March 2019
Posts: 96
|
Post by userscott on Mar 19, 2019 5:30:19 GMT -5
Hi John, With regards your method, that's perfectly clear - thanks for the link. I think I might copy your version with pride, if I can't find some further detail on using syringes. Some questions/assumptions: - I guess I need to get my spark plug to the side, further down the can now, and I assume line it up as best as possible with some of the holes in the flame tube? - I can still squeeze my propane injector somewhere down the side of the evap setup for use when starting? - Do I need to make any notable adjustments to the size of my flame tube given the loss of area to the evap setup? Alternatively... would it be sensible for me to manufacture a tubular ring with perhaps, 8 syringes soldered inside, and place this inside the CC? Feed it with Kerosene at 60 PSI or so and just have the syringes pointing forwards towards the outlet of the CC? I will prepare a 3D model at some point soon once I've firmed up the initial principles, and post it on here..
|
|
|
Post by racket on Mar 19, 2019 17:54:39 GMT -5
Hi Scott
You have quite a serviceable fuel pump for a spray nozzle , and for a first build its probably best to keep things as simple and conventional as possible to minimise hassles, my personal preference now , after having built both spray and evap tube engines, is that I'd go spray if building a DIY sore thumb combustor engine , ............theres a tad more work with the fuel pump but thats more than offset by not having to fabricate the evaps and fuel distribution.................for a micro type engine with annular combustor its a different story .
Cheers John
|
|
userscott
Junior Member
Joined: March 2019
Posts: 96
|
Post by userscott on Mar 22, 2019 9:41:55 GMT -5
Thanks as always John for your continued advice. I have been progressing well with the general components arriving and the laser cutting drawings are making progress. I can only make around an hour a day at the moment but it will pick up soon.. I have acquired 1/4" steel pipe for my Kero line, with an ID of 3.5 mm, and a corresponding 1/4 BSPT compression mount and bung to weld to my end cap. For the spark plug I have obtained a Champion F121501 which is designed for lighting diesel space heaters etc. The tap is for the bottom of the combustion chamber to stop me blowing my bollocks off when I start it up after leaving it standing. The fittings on the right are AN10 bosses to weld to my chassis as I will be storing the oil within the chassis of the train. The laser cutting is quite basic, the purple stuff is the various bits and pieces ready to be cut, the rest still needs fine tuning. The cone adaptors are mostly for my 90 degree bend from the turbo to the CC. I am using 4" pipe for this and so I have to make a square to rectangle to mate this 102mm 90 degree bend into the flange, and make a 102 to 134 cone to get a seamless flow out of the FT. The stumpy cone is just a nozzle for the jet pipe, I'll leave it off for now but it's there if I need it after testing. The turbo itself is looking reasonably healthy. Rightly or wrongly, I got a good deal on the HX55W but of course the W represents wastegate. I've designed an arm to hold the WG port closed on the exhaust housing but I know really, I should be using a non waste gate HX55. There is a scrapper (ex Scania) unit on eBay at the moment which is tempting but the cartridges aren't an easy swap and this turbo of mine is effectively brand new, so I don't want to ditch it unless I absolutely have to.. The oil pump has also arrived. It's an ex Volvo S80 power steering pump. It's an industrial vane type hydraulic pump manufactured by ZF. It's very easy to package and mount, so I'm really quite pleased with it. I just need to figure out what the thread is on the pressure side - not even looked at it yet... Last but not least, the vehicle itself is now back on the workbench and awaiting the hot spanner to remove some bits I don't like from a previous build. The aluminium battery box, fuel tank and seat are all mocked in place.. One is going to get a warm arse set ontop of the CC but the turbo and jet tube should be just above the rear wheels coming out the back.
|
|
userscott
Junior Member
Joined: March 2019
Posts: 96
|
Post by userscott on Mar 27, 2019 5:21:58 GMT -5
Just some small updates today, as I've been mostly busy working on the workshop rather than the things inside! I've been working on the oil pump - it does seem to be a good solid (cost effective too!) pump. The thread on these ZF pumps is M8 for the four mounting bolts, a 15 mm output shaft, and an M8 thread inside the shaft. The outlet is M16 x 1.5. For the motor I have found a cheap 110 watt Paralux (3600 RPM) unit which is 12 volt. It's a strong motor - comes from electric wheelchairs I think. I am hoping to get the right results, but the data for the motor and the pump is so limited I'm just going to assemble it and test it rather than get too carried away doing analysis. Let's see what happens....!
|
|
userscott
Junior Member
Joined: March 2019
Posts: 96
|
Post by userscott on Mar 27, 2019 9:52:12 GMT -5
This is the nozzle I'm planning to use for injection of Kerosene: www.mcmaster.com/3178k51Have I missed anything, does anybody know? It's hollow cone which I believe will be ideal?
|
|
|
Post by racket on Mar 27, 2019 16:56:01 GMT -5
That nozzle should be OK
|
|
userscott
Junior Member
Joined: March 2019
Posts: 96
|
Post by userscott on Mar 28, 2019 11:57:37 GMT -5
Thanks John. Unfortunately they just cancelled my order as they don't like export papers to the UK it seems. Do you have a view on any of the other bits and pieces? I haven't seen that spark plug type used before so hoping it's not a total disaster! My oil pump will end in tears or oil everywhere too I expect! I'll machine up a coupler for it and hope for the best A question I've been pondering was whether to control the kerosene spray via needle valve or PWM controller, or both. I'm wondering whether I can skip the return from the pump if running PWM, if whether it's best to run the motor at 100% and control the injection solely with the needle valve.. I have now found an alternative supplier of nozzles and this place is also selling 180 degree sprays. I'm thinking of the RCZ 2117 nozzle.. www.pnr.co.uk/media/2016/03/page_74_RCY_RCZ_hollow_cone_in-line_spray_nozzles.pdf
|
|
|
Post by racket on Mar 28, 2019 16:32:12 GMT -5
Probably not the best nozzle , flow rates too great .
Fuel control , use a needle valve initially .
|
|
userscott
Junior Member
Joined: March 2019
Posts: 96
|
Post by userscott on Mar 28, 2019 17:39:15 GMT -5
I shall go for the needle valve, it does make more sense the more I think about it... with regards to the nozzle I can only really go down to the RCZ 1780 if I'm reading their diagram correctly. Not sure why there is no dot in the 1/4 column, these nozzles seem fairly hard to find the more I try..!
|
|
userscott
Junior Member
Joined: March 2019
Posts: 96
|
Post by userscott on Mar 29, 2019 9:41:31 GMT -5
Yesterday evening I assembled the relay and connection panel: Accompanying wiring diagram, albeit only a draft: docdro.id/2qbSVeoThe switch panel will be located away from the relays, so the design has been reasonably optimised for that purpose. How effective it will be, who knows. All the gear is Schneider and Wago, including switches and lamps.
|
|
andreirs
Member
Joined: March 2019
Posts: 29
|
Post by andreirs on Mar 29, 2019 10:09:21 GMT -5
I can't say much because my engine is not running yet buuuut... I'm using a oven gas injector, those you would find in your kitchen oven. The smaller ones meant to be used with bottled gas not gas from street pipes. It has a, maybe 0.5-0.7mm hole. Then all I did was chamfer the outside of the hole with a 2mm drill. It is now spraying.
|
|