Guest Mike Posted November 28, 2006 Share Posted November 28, 2006 Mom... I hate to be considered the south end of anything. However I realize I'm often considered as such... not my fault, really. I'm just stupid. How many others here enjoy being the A$$ end of something? Perhaps us ignorant soles should back off and let you intellectuals speak on. We'll just back away quietly and watch in awe. EDIT: What flames are you talking about? Quote Link to comment Share on other sites More sharing options...
Administrators RTz Posted November 28, 2006 Administrators Share Posted November 28, 2006 I think everyone agrees... there is a high pressure zone at the windshield base/cowl. But, the question is, is there a *higher* pressure under the hood? In my limited experience, there is. As was mentioned, its relative. Quote Link to comment Share on other sites More sharing options...
Guest Mike Posted November 28, 2006 Share Posted November 28, 2006 RON... I think you're right. So how do we minimize said under hood high pressure zone? I say with strategically-placed hood and side vents. Quote Link to comment Share on other sites More sharing options...
Dtsnlvrs Posted November 28, 2006 Share Posted November 28, 2006 I think everyone agrees... there is a high pressure zone at the windshield base/cowl. But, the question is, is there a *higher* pressure under the hood? In my limited experience, there is. As was mentioned, its relative. Thankyou, however, I may have jumped the gun on some assumptions (and we ALL know what that is) and started to get upset. For this I am sorry. As far as the flow going back into the engine bay from the cowl, I suppose that at a given speed, the turb at the cowl area may grow to a point wher air is forced back into the engine compartment. There is alot going on in that area of the car. And I do not know, now will I ever profess to fully understand it. As far as temp effecting the boundry layer...do not quote me as this is vague understanding from Aero classes I took while a Flight Engineer....when the temp increases the boundry layer changes (cant remember if it grows or shrinks, sorry guys) but this effects the drag over the given surface. ON SOAP BOX--I hope this clears a few things up. I wont claim to know everthing, its just that having been a crewchief and a flightengineer on both Helos and Fixed wing, I have been subjected to a "Jack of All Trades" sorta Aerospace training. IMHO it can be dangerous 'cause we are taught just about enough in a certain subject to just fix the damn bird, but never enough to fully understand it.--OFF SOAP BOX Quote Link to comment Share on other sites More sharing options...
Administrators RTz Posted November 28, 2006 Administrators Share Posted November 28, 2006 Care to elaborate on that some more? I don't really see how the temperature of the bonnet would affect the boundary layer. Dave, I'll take a stab at this (thats all it will be). Generally, heat is transfered to air at the surface. For example, our weather comes from the sun heating the surface, the surface heating the air, the air becoming lighter and rising, etc, etc. The boundary layer is largely stagnant, yes? If you heated the surface enough, the boundary air would heat and rise, potentially upsetting the boundary layer. My guess, though, is that its 'no factor' in our automobile. Quote Link to comment Share on other sites More sharing options...
Administrators RTz Posted November 28, 2006 Administrators Share Posted November 28, 2006 do not quote me as this is vague understanding from Aero classes I took while a Flight Engineer....when the temp increases the boundry layer changes (cant remember if it grows or shrinks, sorry guys) but this effects the drag over the given surface. Dtsnlvrs, Very coincidentally, you beat me to the punch (regarding boundary layer)... Does what I wrote hold any water, in your experience? Quote Link to comment Share on other sites More sharing options...
Dtsnlvrs Posted November 28, 2006 Share Posted November 28, 2006 Dtsnlvrs, Very coincidentally, you beat me to the punch (regarding boundary layer)... Does what I wrote hold any water, in your experience? As I understand it yes, but I think the effect on are cars would be minimal. However I know that Gulfstream Engineers had to take Boundry Layer separation into account for single engine drift down tables on the G550 with Anti-Ice on. Seems the anti Ice would heat the leading edge up so much with the improved engines, that the old tables for the G-V were inaccurate. Something that they did not learn in the wind tunnel, but through trial and error. Quote Link to comment Share on other sites More sharing options...
Administrators RTz Posted November 28, 2006 Administrators Share Posted November 28, 2006 So how do we minimize said under hood high pressure zone? I say with strategically-placed hood and side vents. Limitless possibilities... how big is your imagination? Quote Link to comment Share on other sites More sharing options...
mom'sZ Posted November 28, 2006 Share Posted November 28, 2006 Mom... I hate to be considered the south end of anything. However I realize I'm often considered as such... not my fault, really. I'm just stupid. Mike... NO NO no, I didn't mean you or anybody else who's post count is above one hundred. Perhaps us ignorant soles should back off and let you intellectuals speak on. tenth grade drop out here. No intellectual... ignoramous is more like it. Sorry man, I just hated to see what looked like a good discussion get muddled by some blow hard know it all telling everybody they must have slept through high school physics. Even though he later came back and said he was joking, if he typed aerodynamics into the search and read for a few hours, he'd come to realize that there are some heavy hitters on this site. If I offended anyone, I appologize. I'll crawl back under my rock now. Quote Link to comment Share on other sites More sharing options...
Administrators RTz Posted November 28, 2006 Administrators Share Posted November 28, 2006 Sorry man, I just hated to see what looked like a good discussion get muddled by some blow hard know it all telling everybody they must have slept through high school physics. Even though he later came back and said he was joking, if he typed aerodynamics into the search and read for a few hours, he'd come to realize that there are some heavy hitters on this site. Easy there... every one has bad day's... even me Group hug? Quote Link to comment Share on other sites More sharing options...
Dtsnlvrs Posted November 28, 2006 Share Posted November 28, 2006 Mike... NO NO no, I didn't mean you or anybody else who's post count is above one hundred. tenth grade drop out here. No intellectual... ignoramous is more like it. Sorry man, I just hated to see what looked like a good discussion get muddled by some blow hard know it all telling everybody they must have slept through high school physics. Even though he later came back and said he was joking, if he typed aerodynamics into the search and read for a few hours, he'd come to realize that there are some heavy hitters on this site. If I offended anyone, I appologize. I'll crawl back under my rock now. No please do not crawl under your rock. We all learn from the discussion, I myself included...and you are right I could have done a search...but chose to get upset and not think things through. I think that for the most part this has been a civilized, and heated at times, discussion and I have learned something new from it...like I said recently, I was basing my assumptions on simple physics, however there is alot more going on in that area of the car than I profess to fully understand. Quote Link to comment Share on other sites More sharing options...
Challenger Posted November 28, 2006 Share Posted November 28, 2006 I think the largest issue of aerodynamics is the fact that the Z's have very large openings in the grill area. From what I know (havent been able to drive my Z on the streets at high speed yet) the Z will have lots of floating, Im guessing this comes from the air in this big opening going out below the engine instead of the hood which would cause lift. Out the hood would help down force and out the bottom would give lovely lift. Quote Link to comment Share on other sites More sharing options...
Dtsnlvrs Posted November 28, 2006 Share Posted November 28, 2006 Easy there... every one has bad day's... even me Group hug? Well put, Anybody want to ask me about Engine Pressure Ratios in Turbofan Engines?? :coollook: Quote Link to comment Share on other sites More sharing options...
mom'sZ Posted November 28, 2006 Share Posted November 28, 2006 No russel, I appologize to you sir. I kind of really kind of popped off. I'm sorry. Quote Link to comment Share on other sites More sharing options...
Dtsnlvrs Posted November 28, 2006 Share Posted November 28, 2006 No russel, I appologize to you sir. I kind of really kind of popped off. I'm sorry. Appology accepted, and now I would like to appologize for hijacking this thread...and now back to our regular programing Quote Link to comment Share on other sites More sharing options...
mom'sZ Posted November 28, 2006 Share Posted November 28, 2006 Is the thread veritech-z linked to the like ten page one where aerodynamics is discussed at length and the aerodynamic engineer gives like a three page discussion on the different 'stations' of the car and how each effects drag, lift, ect? really enlightening. I'll try to find it. Anyhow, mopar69, you are right, closing off a bunch of the grill opening should reap huge benifits. Edit: yeah that is the thread, long read but super informative,good on ya Max. Quote Link to comment Share on other sites More sharing options...
veritech-z Posted November 28, 2006 Share Posted November 28, 2006 I think the largest issue of aerodynamics is the fact that the Z's have very large openings in the grill area. From what I know (havent been able to drive my Z on the streets at high speed yet) the Z will have lots of floating, Im guessing this comes from the air in this big opening going out below the engine instead of the hood which would cause lift. Out the hood would help down force and out the bottom would give lovely lift. In regards to what Russell has going on with his missing cowl seal, I'm guessing that most of the underhood air is exiting the car through the bottom of the engine bay as well. The path of least resistance for that air to take would definitely not be the (at most) 1/4" gap of the hood, but the gaping hole at the bottom, and the trans tunnel. If you've got that airdam close enough to the ground to matter, shouldn't there be a low pressure zone forming behind it that would pull the underhood air down there anyway? I'd be curious to know what the radiator does to the speed of the air passing through it, and in turn how that affects the pressure of the underhood air. Quote Link to comment Share on other sites More sharing options...
Dtsnlvrs Posted November 28, 2006 Share Posted November 28, 2006 If you've got that airdam close enough to the ground to matter, shouldn't there be a low pressure zone forming behind it that would pull the underhood air down there anyway? I'd be curious to know what the radiator does to the speed of the air passing through it, and in turn how that affects the pressure of the underhood air. All good questions that I am not qualified to answer. I do know that I prefer the Fiberglass Air Dam over the Spook style (dont like the eurethane ones as they flex at high speed) and I would be very interested to see baro numbers taken in certain areas behind the radiator, like aft of the engine, in front of the carbs, and have those numbers taken from two identical cars but one with and one w/o AC Quote Link to comment Share on other sites More sharing options...
mom'sZ Posted November 28, 2006 Share Posted November 28, 2006 Easy there... every one has bad day's... even meGroup hug? uhh shucks ron...... Quote Link to comment Share on other sites More sharing options...
veritech-z Posted November 28, 2006 Share Posted November 28, 2006 BJ, when you say your "typical" car has 17X10" wheels and is lowered 2.5", do you mean your typical race car, or the typical car any given member of the forum might be driving? (seems a bit more extreme than mine, anyway I wish my wheels were 17X10" with 0 offset...) Quote Link to comment Share on other sites More sharing options...
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