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Chilled fuel and air

Posted: Tue Feb 22, 11 9:52 pm
by Jon Connolly
http://www.designengineering.com/conten ... more-power


;)



Anyone else using refrigeration ?????????????????????????????

Posted: Wed Feb 23, 11 2:03 pm
by dustymopar
Errr, you? :thumbright:

Would problems be encountered for normally aspirated vehicles for street use? Wouldn't chilled intake air make alterations to engine tune necessary assming that you wouldnt use this continuously?

Posted: Wed Feb 23, 11 3:38 pm
by Jon Connolly
Hi Dusty

No good for road use due to the generation issues ... but definately has a use in drag racing

Did a cold fuel vs warm fuel test on the dyno with Billadeau. It made no difference at all to peak hp. Looked again weeks later at the dyno sheets and the big differences are torque and volumetric efficiency. The engine hits 100% VE ( or over ) sooner and for a longer period.

Took a bit of working out but I am now CONVINCED ... I also think it carries nitrous better ( i.e. further )

I am using a co2 cooler later this year. If you use one be sure to buy R744 and not general welding or dispense co2

:thumbright:

Posted: Wed Feb 23, 11 3:45 pm
by dustymopar
Jon Connolly wrote:If you use one be sure to buy R744 and not general welding or dispense co2
Why is that :scratch:

Posted: Wed Feb 23, 11 3:51 pm
by Jon Connolly
Moisture content, or lack off, won`t block the outlet orifice with ice

Posted: Wed Feb 23, 11 4:12 pm
by dustymopar
R744 isn't a CFC is it? Weren't that used for low-temp ref?

Posted: Wed Feb 23, 11 4:19 pm
by Jon Connolly
No .. it`s a natural 0% odp so do what you want with it

:thumbright:

Posted: Wed Feb 23, 11 4:34 pm
by dustymopar
Can't imagine a man of your calibre went out and bought a kit as in the link - hows yours looking?

Posted: Wed Feb 23, 11 4:51 pm
by Dave-R
What happened to the old trick of just packing a bag of dry ice under the intake? :lol:

Posted: Wed Feb 23, 11 4:52 pm
by Jon Connolly
Just get a plate heat exchanger ... found in any domestic boiler and typically rated 25 - 40 kw in something the size of a box of kitchen matches

;)

Posted: Wed Feb 23, 11 5:06 pm
by dustymopar
I expected something from the 'Building Services' repertoire - good solid engineering :thumbright:

I read that C02 is at 80 below at atmosphere, which is probably what you need to even touch moving air/fuel. Have you measured the delta-t?

Posted: Wed Feb 23, 11 5:23 pm
by Jon Connolly
dave ... ice isn`t low enough temp to start with

i`ve been putting fuel in at upto -53 c already, probably netts down to -20 / -30 c at carb inlet


co2 will probably nett you -50 c at carb ... it is then conduction that cools the incoming air charge i.e. all the carb air passages are chilled without interupting airflow or putting obstacles in air path

By using a 10 / 16 plate insulated heat exchanger you can put a jet on the co2 inlet which turns the rest of the co2 circuit into an " evaporator " with outlet vented to atmosphere. Petrol takes the opposite path to maximise heat transfer.

Control is nothing more than a solenoid valve brought in and out with the same thumb switch I use for nos. Backed up with a widow switch so only works at w.o.t.

Excess co2 is vented to the underside of the car and discharges next to exhausts

Will have it built for first meet :thumbright:

IF YOU SEE A BIG EXPLOSION .. DON`T TRY IT

Posted: Wed Feb 23, 11 5:34 pm
by dustymopar
Perhaps build up slowly with a small C02 metering jet :thumbright:

When is the 1st run?

Posted: Wed Feb 23, 11 6:08 pm
by Pete
...alternatively, use a bigger engine ;) ;) ;) :thumbright:

Posted: Wed Feb 23, 11 6:18 pm
by Jon Connolly
Pete ... you cheeky monkey

:lol: