barr5150 Posted January 29, 2014 Report Share Posted January 29, 2014 (edited) I'm looking for some opinions. I've searched the internet and haven't been able to come up with what I'm looking for. Anyway, take a look at the photo and let me know what you guys think. I have around 100 cranks to tune next week and being in Illinois going to the lake isn't an option. I'm not looking to test the lures just tune them. I'm looking to create a flow or a current in the tank. I already have the sump pump and the tank so aside from a few fittings and a little time I won't be out anything if it doesn't work. My main question is do you guys think the water will flow around the "triangle" ( tin or plywood) in the middle of the tank creating a circular type motion? I'm worried the water might just be very turbulent and not really flow which wouldn't work. Any thoughts or suggestions are greatly appreciated. Thanks. - Bryan Edited January 29, 2014 by barr5150 Quote Link to comment Share on other sites More sharing options...
barrybait Posted January 29, 2014 Report Share Posted January 29, 2014 Look up benchtop test tank in forums. Couple of designs there that members built. Quote Link to comment Share on other sites More sharing options...
barr5150 Posted January 29, 2014 Author Report Share Posted January 29, 2014 I saw that thread from around a year ago. Tons of good info there. I guess in my design I was trying to get the water to flow "over and under" as opposed to a circular motion around the sides. It seems with their designs you only get a couple inches between the sides of the tank and the tubes in the middle. I thought my way would give me more room where the lure is going to be. Quote Link to comment Share on other sites More sharing options...
mark poulson Posted January 29, 2014 Report Share Posted January 29, 2014 A neat concept, for sure. Only trying your design will tell you if it works, and what the problems might be. Unless you're a laminar flow engineer, and can model it on the computer. I would worry that the large triangular area where the lure is suspended would tend to have it's own circular water rotation, instead of the water going around the top of the tank, down the far side, and under the triangular block. One way to try and keep a vortex from forming in that area might be to extend the vertical side of that triangular block that's on the pump side up above the water line, and drill a hole for the pump pipe, to force the water for the pump to be drawn from below the triangular block, instead of some of it coming back over the top. That should promote a more circular flow pattern, especially if you keep your water source up near the surface. And a narrower tank might make the flow more consistent, and help to avoid side vortices. I don't know if this is possible with your sump pump, but rigging a valve in the outlet pipe, so you can control the amount of current flow, might be a good option, so you don't just wind up with a tsunami all the time. Let us know how it works out. Quote Link to comment Share on other sites More sharing options...
Vodkaman Posted January 29, 2014 Report Share Posted January 29, 2014 The flow will be very slow at the lure, but it is a question of how fast does the flow have to be to tune a lure. The design looks like the inverse of a tank that was successful that I remember seeing. If your design doesn't get the job done, you could possibly reverse the triangle and swim the lure in the shallow portion, which in your design is running along the bottom. I didn't explain that very well, but I am tired and it's time for sleep. Dave Quote Link to comment Share on other sites More sharing options...
SCAngler Posted February 1, 2014 Report Share Posted February 1, 2014 Really cool concept! But I agree with vodkaman, the flow will be slow at the lures current placement in the sketch. One thing I do remember from fluid dynamics, haha, is that cross sectional area will affect the velocity of the fluids. Smaller area will increase the velocity. I just recently tried to design one of these and my biggest hurdle was finding a reasonably priced pump to get the flow rate I needed for a cross sectional area of 12". To produce velocities of up to 4 ft/s(~2.75 mph), I needed a ~190 CFM pump! (F****** huge pump) so maybe start with 4 or 5 square inch area... Goodluck! Let us know how it turns out!! Quote Link to comment Share on other sites More sharing options...
A-Mac Posted February 1, 2014 Report Share Posted February 1, 2014 (edited) I tend to agree with Vodkaman. I'm not a fluid dynamics engineer, but I've seen several of these tanks at icast and other shows. I haven't seen a single concept that I thought made the lure run correctly. I would think the pump will throw out some inconsistent turbulence into the water. So consider this my ecological approach! In a stream, you will have riffles, pools, and runs. Riffles are shallow with boulders that cause disturbance and create inconsistent flow and turbulence throughout. Pools are much larger and deeper with slower more homogeneous flow. Runs are shallow, but the flow is consistent throughout with minimal turbulence. The substrate in a run is homogeneous and doesn't cause erratic turbulence. So what we need is to re-create a "run"! In my drawing, flow comes in at a reverse triangle set-up (like what I think Dave is suggesting). This area is open and allows the turbulence coming from the pipe to commingle and (hopefully) reduce. Then water is forced into a constricting point that isn't directly influenced by the turbulence from the pipe. This constriction gradually opens and further reduces the enthalpy of the flow. Then another constriction and the flow comes up into and open area again. Only this time gravity helps to restrict the flow and the flow will "hug" the gradual slope coming up. The red star is where the lure should be tested. To prevent eddying at the tail race, this slope should be gradual too allowing flow to continue to hug this surface to the pipe. It may be more beneficial to have a reducer going from the tank to the pipe on both ends too. Anyway, this idea will more than likely fail... but it's the approach I would take. I think the larger the set-up the better the results. Edited February 1, 2014 by A-Mac Quote Link to comment Share on other sites More sharing options...
A-Mac Posted February 1, 2014 Report Share Posted February 1, 2014 Quote Link to comment Share on other sites More sharing options...
A-Mac Posted February 1, 2014 Report Share Posted February 1, 2014 This one might work better. Quote Link to comment Share on other sites More sharing options...
Jdeee Posted February 1, 2014 Report Share Posted February 1, 2014 (edited) I just use my toilet! Great action on the lures. Every once in a while you even snag a Finless Brown. Sorry guys the long winter is getting to me Edited February 1, 2014 by Jdeee Quote Link to comment Share on other sites More sharing options...
Vodkaman Posted February 1, 2014 Report Share Posted February 1, 2014 A-Mac - I like your thinking. The only thing I would change, would be to remove all corners by rounding off with large a radius as possible. All sharp corners will create vortices, which we are trying to avoid. Using your drawing as a reference, I would still go straight across, from the top of the triangle (right) to the top of the hump (left), keeping the test position the same. Jdeee - The finless brown is called a Mersey trout where I come from Dave Quote Link to comment Share on other sites More sharing options...
Jdeee Posted February 1, 2014 Report Share Posted February 1, 2014 Vodkaman I had to look that up in urban dictionary Here is the definition LOL Mersey Trout A brown object floating in the River Mersey - Liverpool (a Poo) I saw a massive Mersey Trout today - with Sweetcorn eyes! 1 Quote Link to comment Share on other sites More sharing options...
barr5150 Posted February 1, 2014 Author Report Share Posted February 1, 2014 LOL! You guys are nuts! Thanks for all the ideas! I set tomorrow aside to work on the tank. I'll post what I find out. Thanks again! Quote Link to comment Share on other sites More sharing options...
mark poulson Posted February 2, 2014 Report Share Posted February 2, 2014 A-Mac brings up a good point. I use sump pumps all the time, but never noticed if they create their own turbulence, like a trolling motor. Maybe piping the water down so it passes under your central barrier, and has a chance to even out any pump induced turbulence, will give you a more even flow pattern. You could hang the lure right in front of the return water intake. That way the lure would be as far away from the pump turbulence as possible. It's like the air movement in front of the cold air return grill on a house's AC system. You don't feel the flow there like you do in front of the supply vents. I'm not sure how to help you with rounding off the corners. I know, from masonry chimney designs, that the corners of a vertical chimney flue aren't counted in the flow calculations because of resistance. That's why masonry flue liners are oval, to eliminate those "dead" corners. Maybe you could use a flexible material like a piece of Formica to bend around the bottom corners, and to help redirect the up flow back toward the intake at the top corner. Just a thought. Good luck, and let us know how your tank project works out. Quote Link to comment Share on other sites More sharing options...
Vodkaman Posted February 2, 2014 Report Share Posted February 2, 2014 Mark - corners cause turbulence because the flow cannot change direction so suddenly. This creates a dead zone on the lee side of the corner, think of it as a vacuum. This low pressure pulls the flow back towards it, creating vortices or turbulence. The bigger the radius, the less turbulence. The formica idea is good, that would do the trick. The flow probably doesn't have to be perfect anyway. We may be anticipating problems that simply aren't there. Dave Quote Link to comment Share on other sites More sharing options...
A-Mac Posted February 2, 2014 Report Share Posted February 2, 2014 I agree entirely with rounding the corners. I think the width of this set up will be just as important too. Since water is "sticky", it will be attracted to all surfaces, including the sides. I think having some width to this system will help to reduce impact on the area the lure is to be tested. Can we make this any more complicated???!!! Hell, I can barely get a crankbait lip straight, let alone predict invisible vortices. ...bar5150, your wife is going to wonder why you just didn't buy a pool... but on the plus side, you may be able to rear trout in this thing! Good luck! OOooooo, once it is built it would be neat to see a dye test too! Quote Link to comment Share on other sites More sharing options...
diemai Posted February 2, 2014 Report Share Posted February 2, 2014 Came across this ingenious design the other day , ........rather made to observe the action of tuned trolling spoons without having to toss each and every one behind a boat , but probably could provide some input , especially in terms of generating a steady current by means of an electric boat motor . Greetz , diemai Quote Link to comment Share on other sites More sharing options...
mark poulson Posted February 2, 2014 Report Share Posted February 2, 2014 (edited) Man, that is THE test tank. Thanks. Dieter, do you have the link to that video? Edited February 2, 2014 by mark poulson Quote Link to comment Share on other sites More sharing options...
diemai Posted February 2, 2014 Report Share Posted February 2, 2014 (edited) Somehow the linking won't work , Mark , ..........it's always the video appearing , not just a clickable link ! Click on the video title above the picture , this would open up the original YouTube video site , so you could paste and copy the link from there , shown on top of page , as the vid is playing . Sorry , don't know any other way , .......greetz , Dieter Edited February 2, 2014 by diemai Quote Link to comment Share on other sites More sharing options...
mark poulson Posted February 2, 2014 Report Share Posted February 2, 2014 Thanks Dieter. Quote Link to comment Share on other sites More sharing options...
barr5150 Posted February 3, 2014 Author Report Share Posted February 3, 2014 UPDATE - My idea sucked! I tried a hundred possible configurations and the best I could come up with is pictured below. Everything I tried just created a tsunami inside the tank. Definatly harder then I though. I think my original idea would work if the tank was about 3 times larger. The tank I have is just too small. The set up I have now isn't perfect but for what I have invested it works OK. Thanks for all the help and ideas http://i1000.photobucket.com/albums/af125/barr5150/FinalTestTank_zps09e7bc46.jpg <a href="http://s1000.photobucket.com/user/barr5150/media/FinalTestTank_zps09e7bc46.jpg.html" target="_blank"><img src="http://i1000.photobucket.com/albums/af125/barr5150/FinalTestTank_zps09e7bc46.jpg" border="0" alt=" photo FinalTestTank_zps09e7bc46.jpg"/></a> Quote Link to comment Share on other sites More sharing options...
mark poulson Posted February 3, 2014 Report Share Posted February 3, 2014 I'm sure you can work it out. You've done most of the hard work already. What kind of a tank are you using? Quote Link to comment Share on other sites More sharing options...
barr5150 Posted February 3, 2014 Author Report Share Posted February 3, 2014 Just a fish tank I had laying in the closet. It's pretty tall but only 2 1/2 foot long. I like summer a whole lot better! I can walk to the end of the street and test lures in a detention pond. Quote Link to comment Share on other sites More sharing options...
mark poulson Posted February 3, 2014 Report Share Posted February 3, 2014 I see that you incorporated a valve to control flow. My experience with sump pumps is they are strong, and it would be hard to cut down the flow too much without burning them out. Maybe a smaller pump, like for a big aquarium, would work. Quote Link to comment Share on other sites More sharing options...
barr5150 Posted February 3, 2014 Author Report Share Posted February 3, 2014 A friend of mine suggested the same thing. Being a cheap a$$ I was trying to use what I had. Believe it or not the sock over the outflow was the key to the whole thing. It's like it diffuses the water coming out of the pump so it's not so turbulent. Quote Link to comment Share on other sites More sharing options...
