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#21
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In article , Barnyard BOb --
writes: The fellow of which you speak is Henry "Smokey" Yunick. He was my hero back in the 50's, when I was the average impressionable teeny bopper subject to spouting stuff like you. Oh my God! Here I thought that the only hero you ever had was that old coot that stares back at you from the mirror every morning. BFG Bob Reed www.kisbuild.r-a-reed-assoc.com (KIS Builders Site) KIS Cruiser in progress...Slow but steady progress.... "Ladies and Gentlemen, take my advice, pull down your pants and Slide on the Ice!" (M.A.S.H. Sidney Freedman) |
#22
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AND, patents are issued by the US Government AND they retain certain
rights in return for the protection they afford. Just like trying to sue the Government, it's their party. "Michael McNulty" wrote in message ... "Russell Kent" wrote in message ... Ernest Christley wrote: The military is exempt from patent restrictions, I doubt that statement is true, but I have no facts to either prove or disprove the statement. In any case, the U.S. military does not (as a rule) manufacture much of its own equipment. That is done by subcontractors who are very much bound by U.S. patent law. Russell Kent Actually, the normal U.S. military development contract has a clause called "authorization and consent" that specifically authorizes the contractor to infringe on any patents that it sees fit too, and whereby the U.S. government consents to accept any liability associated with this infringement (i.e. they agree to allow themselves to be sued by the patent holder). Believe it or not. |
#23
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Did you have a look at Smokey's drawings and facts on his working
engine in a car, before you posted this? Richard Isakson wrote: "Orval Fairbairn" wrote ... I believe that the thermodynamics involved don't fit the problem. Evaproating the fuel as it goes into the engin won't provide sufficient cooling to do the job. Snicker. You got that right! Gasoline has a specifc heat of 0.50 BTU/lb/deg F and a vaporization point of about 350 deg F. Heating the gas from 70 deg to 350 deg could absorb 140 BTU/lb from the exhaust out of a total of 18,000 BTU/lb that will be burned. Darn it, I missed another free lunch. Rich |
#24
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Gasoline has a specifc heat of 0.50
BTU/lb/deg F and a vaporization point of about 350 deg F Gasoline's endpoint is 350 F... half of it is vaporized by about 180F... and it starts vaporizing just under 100F... remember, it's a mixture of hydrocarbons. Of course, you get more bang for the buck than just the specific heat... you get the heat of vaporization as well, eh? Paul |
#25
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Sorry it took so long to get back but I'm in Hawaii right now so
access to the internet is limited (laptop+digital cell phone). The vast majority of GA engines don't use radiators so none of the large manufacturers are interested in pursuing a project with only a niche market (and budget concious one at that), so this may be another reason. And you bring up a good point, who can build one and the rest of an entire airplane. Most people are so busy doing all the other things the have to do (work) to be able to spend time/money doing experiments but thats part of the reason for bring it up here- so we can get lots of eyes and brains on the problem. Some people that have done work in this area can bring up points, and maybe somebody will say "I work in a brazing shop, we make something like that for XYZ application." I've seen some stuff real close done by the guys that do forced air cooled cabnets for avionics. No doubt, construction will have to be done by a specialist or someone that will become a specialist. I'm writing in this newgroup more for the expermintal part and less for the home made part. Mechanical stresses- I can definitly see this would be a problem if the radiator is a structural element or ridgedly attached to one at multiple points, but what I'd imagined was some part (or whole) of the lower cowl. That cowl region being critical because it has access to that nice cooling turbulent air right behind the propeller. 3 blades might do better than 2 for this style cooling. The only weight it has to support is itself. These things are often times fiberglass so they aren't all that strong. From what I've read of the radiator imperical studies from the "golden age", producing a turbulent flow was key cooling efficiency per unit area. For a low speed aircraft (100MPH) an auto radiator makes more sense than something custom like we're talking about here. Regards |
#27
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Surface Area? A standard auto styled radiator has a tremendous serface area packed into a very small and light package. The air is forced through that surface area with contact normally on two surfaces as it passes. To obtain the same surface area on a single sided flat plain would take much more area than is available on the underside of the cowling. You might be able to get enough area by using the whole underside of the fuselage but you still don't have the same type of contact. Bob Reed +++++++++++++++++++++++++++++++++++++++ Bravo Bob, but no matter how you say it... there are dreamers and wannabees that just can't let go no matter what. Evidently, living without the Easter Bunny, Santa Claus and the Surface Radiator Fairy is unthinkable. Barnyard BOb -- stranger than fiction |
#28
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Bob had mentioned the surface area thing as well, and this is a linear
relationship, but what I'm refering to is turbulence which has an exponential relationship to the effective heat transfer capability of that air mass. As you may know, in clean air, a film of heated air clings to the interface between the metal surface and the air mass as it passes by, this impedes heat transfer. A car radiator, while being small and available, is also exceedingly draggy, which is why its not an optimal choice choice for a fast airplane. The auto radiator is designed for different conditions mainly: 1) High disipation at low air flow speeds 2) Clean air entering front surface (Reynolds number less than 10,000) 2) Drag not an issue An aircraft/cowl-surface scenario doesn't have the condition of high power output and low airflow and thustly should not besigned for this condition. Even on the climb out, while the IAS may be low, the prop wash is turbulent and higher in velocity than the speed of the vehicle itself. Regards |
#29
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In article , Barnyard BOb --
writes: Surface Area? A standard auto styled radiator has a tremendous serface area packed into a very small and light package. The air is forced through that surface area with contact normally on two surfaces as it passes. To obtain the same surface area on a single sided flat plain would take much more area than is available on the underside of the cowling. You might be able to get enough area by using the whole underside of the fuselage but you still don't have the same type of contact. Bob Reed +++++++++++++++++++++++++++++++++++++++ Bravo Bob, but no matter how you say it... there are dreamers and wannabees that just can't let go no matter what. Evidently, living without the Easter Bunny, Santa Claus and the Surface Radiator Fairy is unthinkable. Barnyard BOb -- stranger than fiction I understand the dreamers and wannabees but don't understand wanting to reinvent the wheel. The idea of surface cooling is not a bad idea until you get to looking at the details of what has already been tried and why is was not a success. Many of the current advances in all areas is being achieved by using old ideas with some of the modern materials and methods. If there was some new materials available which could make this a plausable concept then more power to them, it might work. Bob Reed www.kisbuild.r-a-reed-assoc.com (KIS Builders Site) KIS Cruiser in progress...Slow but steady progress.... "Ladies and Gentlemen, take my advice, pull down your pants and Slide on the Ice!" (M.A.S.H. Sidney Freedman) |
#30
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The auto radiator is designed for different conditions mainly: 1) High disipation at low air flow speeds 2) Clean air entering front surface (Reynolds number less than 10,000) 2) Drag not an issue An aircraft/cowl-surface scenario doesn't have the condition of high power output and low airflow and thustly should not besigned for this condition. Even on the climb out, while the IAS may be low, the prop wash is turbulent and higher in velocity than the speed of the vehicle itself. Regards Well, since you already have it all figured out and know all the answers what are you waiting for, do it. We are obviously unknowing of the solutions which you have worked out and are waiting to be proved wrong. Bob Reed +++++++++++++++++++++++++++++++++++++++++++ This is the same class of dreamer and wannabee that was discussed earlier. This ilk will not only reinvent the wheel with Unobtainium, but is also famous for wasting perfectly good restaurant paper napkins at lunch time. Barnyard BOb -- Have sharp stick. Will travel. |
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