What about running a pressurized gas through an air/liquid intercooler rather than iced water? This is what I'm thinking. The common practice is to carry along a large water tank, water pump and plumbing. During the course of a run the water is circulated through the intercooler to cool it. The water picks up heat and is continually recirculated through the run. As the water picks up heat, the water recirculated back to the intercooler will begin to warm in temperature by the finish of the run. The cooling affect of the cooling medium changes throughout the run. The water in the intercooler must be changed out with each pass and a large supply of ice must be hauled to the track and properly stored, to be added to the intercooler tank for each pass. That seems like a lot of work to me. Of course, that extreme of intercooling is not always necessary when you're burning methanol, but at higher boost levels, a certain level of intercooling can still have some value, even with methanol. Water will also corrode the intercooler core requiring that the core be changed out every so often. Now we switch to a pressurized container of a cooling gas. CO2, liquid nitrogen, nitrous oxide. The container is simple and quickly changed out. No pump is required. The cooling medium is not recirculated during the run, so the level of intercooling stays the same all the way to the finish of the run. There's no messy changing of fluids and awkward storing of massive amounts of ice and water. The level of intercooling can be adjusted by metering the gas flow from the pressurized cylinders. The weight of the cylinder changes during the course of the run. The flow of the cooling medium can serve other purposes on its way to and from the intercooler, if needed. For instance, if you're running an inlet tube to the compressor housing, wrap another tube around it and form a chamber where the cooling gas can cool the inlet tube before going on to the intercooler. Pre and post compressor cooling. And after the cooling gas passes through the intercooler, dump it into the exhaust pipe after the turbine to cool the exiting gases. Cooler, denser exhaust gases traveling at a slower speed through the exhaust pipe at a lower pressure, promoting exit flow from the turbine.
Sounds OK on the surface but would probably not work well and this is why, The interior of the "Water" area is desighned to transfer heat to the water. If using inert gas, it would most likely form a slow moving boundry layer against the interior walls and actually insulate the transfer of heat to to high volume of moving gas on the central areas of the intercooler. It would be better to have some sort of fins on the interior to conduct the heat and to give the gas something to flow over and remove the heat. Allan G.
How about this outragous idea, pump your unused Alky through the intercooler ? Fuel cell and cooling media - dual purpose. Allan G.
So an encased air/air intercooler core would work best. Perfect. The intercooler core would be mounted flat below the radiator support, just like my present intercooler is. The cooling gas would be introduced below the core and would collect at the bottom of a shallow tank there. It would eventually flow up through the core and would exit from a tank above the core. From there it could be directed to the exhaust pipe. The cold nitrogen liquid/gas likes to settle at the bottom, so the gas would even out on the bottom of the shallow tank before eventually being forced up through the core by the mounting level of the cooling gas being fed into the bottom tank. The flow rate would be controlled to provide the maximum heat transfer. In my case, I would really only need a little bit of cooling. Probably wouldn't require too much of a feed rate. That would allow the contents of the bottle to last through multiple runs. No messing around with changing out water and ice.
A liquid cooler will take 300 degree air and send 60 degree air to the engine. An air-air may take in 300 and put out 120. How much intercooling would you even need with alky to justify anything other than a simple air-air.
As I push the boost over 30 psi boost with the new configuration, I will need a little more intercooler help than what I'm getting with the present dry air/liquid intercooler. With the Stage I config, by the end of the 1/8, intake air temp is about 90C. This is in the up pipe before fueling is introduced into the mix. That's about the limit as far as how high I want to see the IAT get. I don't want to open the grill up. I'd rather keep it blocked off. A small enclosed air/air unit using a coolant other than ambient air may be enough for what I need. Like I already stated, I don't think I'll be needing a bunch of intercooling. Just more than what I'm presently getting. Plus, I can precisely control the amount of intercooling by controlling the rate that the coolant is fed to the intercooler. I'm guessing that I will have to ramp in more fuel for combustion cooling as boost levels move higher, but the amount I will have to ramp in will be less if I can properly control the IAT. I may find some power by not having to do all the combustion cooling with a very rich air/fuel mixture.
I'm not an alky expert, but most of the alky fueled drag only cars I've seen run no intercooler and no cooling system. Why is your car different? Why add another bottle of compressed gas, complicating things even further and adding more weight. The amount of systems you have going on reminds me of the space shuttle launch.
Most blown alcohol applications don't use boost numbers much over 30 psi. The ones that I've known to boost much over 30 psi have an intercooler. Liquid. Most blown alcohol applications are towed to the burnout box, then towed back to the pits. Most blown alcohol applications have to change the engine oil after each run down the track. That is because they run a very rich mixture to cool the combustion chamber instead of using an intercooler. That quickly contaminates the engine oil. And because they don't have a cooling system, they can't let the engine run warmed up long enough to boil out the fuel and water content that accumulates in the crankcase. Water? Water is 1/2 of the by-product of burning methanol. It's part of the blow-by. I didn't want to be saddled with the hassle of towing the car, and having to change the oil after each run. That is why I have a cooling system. I also ventilate the crankcase. The car could be driven on the street if it was legal to. Adding a bottle, seems to me, would be much simpler than the circus others go through in the pits dealing with a huge water tank and icing.
One reason why most blown alcohol applications don't run water in the engine is to prevent the cooling system from becoming pressurized if a head(s) were to lift a little, resulting in the possibility of blowing a hose or something else during a run. A safety issue.
Liquid nitrogen is VERY cold and will freeze up the core solid if there is ANY moisture in the intake air. Your intercooler will become a HUGE restriction if you spray nitrogen across the core. AND......There is a big safety concern. You loose a hose/fitting, or have an "issue" while changing/filling your bottle, better have 911 on speed dial. -195*C is too cold for any moisture in the ambient air. Alcohol and ice would be a better choice. Not sure if NHRA would be cool with that, though. 50/50 mix water alcohol would be non flammible so why not.
Don, Do you think that there will be any issues at the transition points in the map ? I would think that there may be some difficulty with controlling rich/lean conditions. Allan G.
The Stage I project used one similar type of transition point with the mechanical nozzles I'm using. There is a timing (not ignition timing) issue that has to be worked out, but it's quickly remedied and once it's dialed, you can't even tell it's there. I suspect the transition point for the staged electronic injectors will be even easier to dial in, if any dialing-in will even be necessary. Edit: Dialing in the mechanical nozzles takes about as long as dialing in a new boost controller. It's really a piece of cake. It just seems difficult if you've never done it.
I've been brain storming about my new intake design. It's going to be wild. Wilder than the Stage I project. The air will enter the plenum through the floor, sides, or both, leaving the roof open to configure any way I need. All the fueling, including the nitrous will be introduced through the roof of the plenum, injected directly down the entrance of each intake runner. That will be two electronic injectors, one mechanical fuel nozzle, and one wet nitrous nozzle.
In the tube feeding the plenum, use 1 or 2 guide vanes. The tube will be rectangular transitioning to circular once past the front of the plenum. That is where the throttle body will mount. The rectangular section will make it easier to divide the tube into equal area sections with the guide vanes.
\ FWIW outlaw blown methanol guys runs considerably north of 30 psi, freind runs 45 on his methanol outlaw. drives the return road back and no oil changes between runs.
