....I am still intrigued by the double fin behind the wheels as you say....
The only advantage I'd see with two vertical stabilizers would be if there was a wing between them for your added downforce. Otherwise there is more aero penalty to be accrued with no real gain in center of pressure with two over one. A vertical stabilizer is going to have more effect on CP than a canted one. Then again you would need two along with their added drag. Saying that properly designed verticals and a wing for downforce don't necessarily need to add a lot of drag. They both can have Cd's down under .1 and very little frontal area.
On Hooley's Stude we have added no weight behind the axle and considerable weight ahead of it but then also more weight further ahead to keep the CG forward. So you end up with a lot of weight that is doing nothing for traction but still needed for safety.
I guess I missed it but are you converting the tank to a streamliner or is this a whole new car? Also you coming this way at all? We'd love to see you. Ruth said to say hi to you guys, me to 
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Sum
Hey Sum great to hear from you, its been a while.
The idea is simply a different body to the car so we can be in streamline class. We will still run both bodies and improve both as we go.
the issue for me is I am out of the game a bit, firstly living in the UK means I cannot do the weekend assists on the build and as it is mostly mechanical that is Dr G and the Colonel's forte not mine. So I want something new to design and play with! I expect it to take awhile to get right but if you keep chipping away and surround yourself with smart people and ask a lot of questions (hence here) we should see progress and one day hopefully have something on the car.
Your comments as always are spot on. You might be back on the scene but certainly not slow! I am very keen to use an under body ground effects system with a diffuser at the back to assist it in downforce for minimum drag. This is where two tailfins can help create the endplates to help pull air out of the tunnels under the car increasing the air speed and hence lowering its pressure (benouli effect). This is my favourite sort of design where everything is working holistically to create one great solution but I need to know the pros and cons of each element to see how best they go together to cancel each others cons and promote the pros.
Why use ground effects? Well the trend for streamliners has been to be narrower and more dart like. We don't have this option as we will be using the existing setup but that means we have both pros and cons. The cons are wider frontal area but one pro is that that gives us space to use ground effects tunnels either side of the car which can give us more downforce for cheap if designed correctly (and admittedly this is a big if). I have a design hunch that the simple solution of a dart is not necessarily the fastest solution for a wheel driven car. It's fine for a rocket, Bloodhound SSC, Aussie invader etc, but they want to be as neutral as possible. Wheel driven cars need to get that power to the ground and the options are weight or aero downforce. Weight is part of the solution but there is a limit, for example, you still need to be able to get up to speed in the 7 miles and if you are two heavy for your power that is simply not going to happen in that distance. Being lighter means you can accelerate quicker (if you can get the power to the ground) which means you should be able to go faster over a given distance given the right circumstances. What I am trying to figure out is what those circumstances are and design our car for that gap in the market!
Hopefully will be visiting this September Sum! Would you believe that Alice, our daughter who Amber was pregnant with when we visited you, is now in primary school???!!! It's been way too long. Please say hi to Ruth too, I still can taste in my mind her delicious dish she cooked for us.
Dik
Topic: Australian Belly Tank (Read 3516250 times)