P Port progress

[J Berki]

I finally got the water jackets on the modified rotor housings sealed. They held 60psi for a day and this was done while the housings were submerged. A split clamp was turned and an O ring held by a ring will complete the seal to the slide throttle side plate. Here are some pics

Joe Berki
Limo EZ

[TMann]

Looks pretty cool !

[J Berki]

Made some progress on the augmenter. I pieced together some foam and roughed in a duct that will take air from the back of the rad and oil cooler and dump it into the augmenter tube. I hope that there is enough space behind the rads for proper flow but the Long EZ engine compartment is tight ( mockup engine installed). I plan to feed the augmenter from the headers but have room for a spintech muffler when I realize that it is too loud, maybe.
Here are some pics.

Joe Berki
Limo EZ

[John Slade]

Interesting approach!
I'm convinced that good augmentation is the key to cooling a rotary on a pusher.
I look forward to seeing it fully implemented.

[Buly]

Joe, how are you going to route the exhaust tubes into the augmenter?
Just curious?

[CBarber]

Ah, another opportunity to show my ignorance. Exhaust agmentation is a term I keep seeing but have no idea what it acutally means. Considering I am currently working on my exhaust pipe out the back of the turbo, with a heat sheild surrounding it, this may be the proper time to ask.

Attached are a couple of pix I took last night after very roughly cutting out the cowl to let the pipes exit out the back.

All the best,

Chris

Sorry for the highjack....it is a rotary though.

[J Berki]

Buly and Chris,

An exhaust augmenter is a duct system, in the case of a liquid cooled engine, where air is pulled through the heat exchangers by the presence of the exhaust from the motor being dumped into the duct after the heat exchangers, facing aft creating a vacuum.

I originally planned to route the header pipes forward then up next to where the oil injection pump used to be joining the two pipes in a Y then upward to the forward end of the black pipe in the last pic. This Y could also be a spintech muffler mounted vertically using the muffler as the collector with 2 in 1 out.

I am thinking about making the vertical part of the duct out of metal and routing the header straight forward into the duct ending the pie pointing upward but I am not sure if that will work plus added weight.

Joe Berki
Limo EZ

[John Slade]

Chris,
Your exhaust looks a lot like mine. All you have to do is chop off that exhaust pipe a few inches short of the exterior outlet. The air flow from the exhaust will create negative pressure inside the larger diameter pipe. This sucks air through the large pipe from the forward end. The ideal is that the forward end of the pipe is ducted to the outlet from the rad & oil cooler but, even without this ducting (which I couldn't fit), the air will be coming from inside the cowl - thus you are using the pressure of the exhaust to suck air through the system.

I'm sure the effectiveness of this technique will vary a great deal depending on the sizes of the two pipes, the distance from the end of the internal pipe to the exit, the ducting etc. etc. A thermodynamics engineer could probably spend a lifetime doing the math and perfecting it (and then find out that the perfect augmenter can't be made to fit in the cowl).

I really don't know the relative value of an augmenter. Maybe it makes a 2% improvement. Maybe 10% - but I do think it's positive so using the "it can't hurt and it's easy" philosophy, you might as well do it.

I read Eric Westland's analysis of belly vortilons to help airflow into the Naca and various articles about augmentation, implemented them both and they've been there ever since. I suspect that the augmenter helps ground cooling more than it does airborne when you have plenty of airflow anyway. Anything that helps airflow through the system is going to help your cooling.

Anyway, one hacksaw cut will get you a augmenter. My exhaust ends about 2 inches from the average of the end of the outer pipe. 3 or 1 inches might be much better. No doubt scientific experimentation is the best way to find out what works best, but I think it would be difficult to get meaningful results with all the variables involved.

[J Berki]

Got a few things done. I elected to make the duct work from the rad and cooler side to the ejector out of glass at the rad then transition to furnace duct which looks like it will work and seems lighter than a glass part. The metal portion will permit me to route the 32" headers inside of the duct as they dump into the ejector pipe. This will shield the engine compartment. The headers are downstream from the rad and cooler so I hope there is not too much radiant heat as the air is going away from the rad and cooler.

Picked up a rad from Summit Racing which is shorter than the oil cooler and required widening the frame and the supporting structure 1". I will need to change the rad outlet to a hard 90 degree as it is under the engine. The oil pan forms a tunnel where the tube will emerge on the left side of the engine. The rad being shorter enables the oil inlet line to connect with the oil cooler .

Here are some pics

Joe berki
Limo EZ
13b

[J Berki]

I got the frame widened to accommodate the summit radiator. This also required cutting and adding foam and glass to the fuselage. Put the whole thing together to check clearances. I found the metal duct at Home Depot. From the bottom pic you can see the frame and two pieces of wood representing the radiator thickness. The diffuser, mocked up in scrap foam, can be one piece and sealed to the backside of the frame. The oil pan comes close but the rad is shorter than the oil cooler. The only way the metal duct could be lighter is if I made it out of carbon, but it would not take the header heat.

Joe Berki
Limo EZ