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You guys could improve the test. Just throwing out the concept.
I don't doubt your sincerity, Al, and the objective is admirable, but I think it would be VERY hard to achieve any real science comparing different installations, even on the same aircraft type at the same place on the same day. There are just too many variables. Inlet duct size & shape, outlet size, airflow through the cowl, position of the heat exchangers, augmentation system design, overall drag, engine model, accurate measurement of actual results... the list is endless. There would always be enough noise in the data to render it meaningless, especially with plans built airplanes like the Cozy. I believe that the ONLY way for each individual to approach the optimum is first to establish what it is and then for them, then approach it scientifically by changing things one at a time measuring airflow, cooling and drag effects accurately as they go. This will be a very tedious exercise involving lots time consuming redesign and rework, and its what many here have done over the years to get us newbies to the point we're at today. The reality of putting one of these installations together from scratch is an exercise is that you read and learn, look carefully at what other flyers have done, decide what you think is best of all you have seen and learned, then assemble your own approximation of a solution to meet your own particular goals. There's enough information around these days that, with a bit of luck, your first shot will work well enough to fly without overheating. Once you reach this point you can begin the exercise of improving the cooling / cooling drag equation by experiment. The holy grail is getting something that works (ie meets your own design criteria) first time. It's EZ to err to the side of cooling drag and get something that cools but wont go fast. Its a lot harder to hit the target of something that goes fast and still cools enough. Its all about experimentation and compromise, with a little luck thrown in.
John Slade
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