ParDeus Posted February 2, 2014 Author Report Share Posted February 2, 2014 Lol. Anyhow, more data. When I flow a cylinder head, I roll up some playdo, and form it around the mouth of the port, to create a 180deg radius, about 9/16" in width. This is pretty standard practice, and it increases flow by at least 30% compared to the 90deg entrance. SO... When I flowed my test mdf ports, I used a roundover bit on the inside of the port entrance, and on the 4x2" test port, it increased flow by 24% at a 28" water column. I then glued shoe molding around the exterior circumference of the port entrance (to make the 180deg radius mentioned earlier) and total flow increased 28% over baseline. Also, the measured localized velocity at the mouth was far more uniform, and using flow visualization, the flow was far more linear. I'm sorry, but at the time I didn't think I would be sharing the results, so I didn't put the velocity and flow linearity into any sort of comparable standard. That is an easy test to replicate, and I will do so and add some relatable data. I would love to add video of the visualization, but there is a strict no camera/video rule in my shop, for obvious reasons. However, I will see about being very "discrete", lol. So, my opinion is that it is good to round over your port ends, and that adding more flare (think of a true bellmouth) to aeroports would net a worthwile gain in turbulence reduction and total mass flow. I cannot say with certainty, however, that that = more DBs. Pastry time, (I woke up late, the day is damn near wasted), but I will go to the shop today and start assembling the tline enclosure. I will try to use a plexiglass top piece to make everything to visually relevant. Link to comment Share on other sites More sharing options...
ParDeus Posted February 2, 2014 Author Report Share Posted February 2, 2014 Just to clarify, flared radius =! 45's. Any sharp turn over 14deg really pisses air off. Link to comment Share on other sites More sharing options...
timc31610 Posted February 2, 2014 Report Share Posted February 2, 2014 Im tuned in, and pretending I know what is going on! My Build Log 94 Civic http://www.stevemeadedesigns.com/board/topic/188644-94-civic-4-door-build-loq-suggestions-wanted-will-be-super-slow-mo/ Faceebook reluctantly Link to comment Share on other sites More sharing options...
Dwn4BassAlan Posted February 2, 2014 Report Share Posted February 2, 2014 lol^ And I wish all the new members could be like you in some way at least. I appreciate you getting all the data for those of us too lazy or too dumb to do it ourselves haha Biomedical/Behavioral Science Major, The (Self-Proclaimed) Undisputed-Homemade-Woofer-King Super-Neodymium-Woofer Build Log: The D4BA-V.2 http://www.stevemeadedesigns.com/board/topic/169236-diy-super-neodymium-woofer-build-log/?p=2475620 Fucking love Alan you goddamned fucking super nerd lol When Alan uses big words I don't understand It's warming up enough that the donut-punching cyclist douchenozzles are getting their two wheeled fagmobiles out. Everytime I see a guy driving a mini cooper I cant help but think he loves cock & (2/29/16)-My wife just bitched at me about throwing out things we don't really use. My response of well we don't really use your vagina so should we throw that out was evidently not the right response. I had to leave the room. I missed Alan. RIP 5/29/15 - I love you son. Link to comment Share on other sites More sharing options...
bassaholicsfl Posted February 2, 2014 Report Share Posted February 2, 2014 Well not everyone here has years on years experience engine building dealing with air flow. But hey all I do is bend sheetmetal, machine aluminum, and operate a punching machine. Lot of us normal people don't have access to all the tools he does. 2001 Dodge Ram Quad Cab. Link to comment Share on other sites More sharing options...
Krakin Posted February 2, 2014 Report Share Posted February 2, 2014 Well not everyone here has years on years experience engine building dealing with air flow. But hey all I do is bend sheetmetal, machine aluminum, and operate a punching machine. Lot of us normal people don't have access to all the tools he does. What is the point of getting upset? Not like Alan or I have the meters this man has, however it would be really cool to have an air velocity meter to do some testing and see how close that WinISD can get to predicting the port velocity. On another note, can someone explain how dimpling increases the maximum effective velocity? Krakin's Home Dipole Project http://www.stevemeadedesigns.com/board/topic/186153-krakins-dipole-project-new-reciever-in-rockford-science/#entry2772370 Krakin, are you some sort of mad scientist? I would have replied earlier, but I was measuring the output of my amp with a yardstick . . . What you hear is not the air pressure variation in itself but what has drawn your attention in the two streams of superimposed air pressure variations at your eardrums An acoustic event has dimensions of Time, Tone, Loudness and Space Everyone learns to render the 3-dimensional localization of sound based on the individual shape of their ears, thus no formula can achieve a definite effect for every listener. Link to comment Share on other sites More sharing options...
ParDeus Posted February 2, 2014 Author Report Share Posted February 2, 2014 Basically, texturing the surface of a port will create a turbulent boundry layer, which promotes adhesion of the airstream and overall more flow linearity. This will lower some localized velocities that were caused my turbulent mass flow, however it equates to a higher controlled velocity because energy is not lost due to chaotic tumbling. Also you get more net flow/energy transfer. Link to comment Share on other sites More sharing options...
ParDeus Posted February 2, 2014 Author Report Share Posted February 2, 2014 Btw, I love the implication that I am abnormal, lol.^^ Link to comment Share on other sites More sharing options...
bbeljefe Posted February 3, 2014 Report Share Posted February 3, 2014 Basically, texturing the surface of a port will create a turbulent boundry layer, which promotes adhesion of the airstream and overall more flow linearity. This will lower some localized velocities that were caused my turbulent mass flow, however it equates to a higher controlled velocity because energy is not lost due to chaotic tumbling. Also you get more net flow/energy transfer. Correct me if I'm wrong but isn't it simply stated that the turbulence created by dimpling creates something of a cushion of air for air to flow around... thereby decreasing friction. Not unlike a maglev? Facebook: facebook.com/audioanarchyllc Instagram: audioanarchyllc Youtube: youtube.com/bbeljefe Link to comment Share on other sites More sharing options...
boom50cal Posted February 3, 2014 Report Share Posted February 3, 2014 OP is too fucking cool. Likes going fast and getting loud. On 1/4/2013 at 9:31 PM, HatersGonnaHate said: Wow. 184 posts and I think you're a fucking asshole. Link to comment Share on other sites More sharing options...
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