WA
1 posts
I am involved in an art exhibition based at Townsville september 05, I will be entering a project called 'BoB' that consists of 15x 15m scatterd carbon fibre poles that are designed to amplify water current and wind movements on the inshore ( approx 400m to 700m off the shore line).
I need some feedback in the area of bouyancy durived from polystyrene in salt water conditions. I am finding it difficult to nail down what one cubic metre of display grade poly will carry ie to just above neutral bouyancy, taking into acount displacment. For this volume block would like approx 75% of the block submerged!
Once I have gained this ratio I can then get on with design.
Secondly, is there anyone who has expertyise in keel design - in particular - what lenght and weight rerquired below the turning point to counter react / offset the windlopading of a flexable ( rather like and oversized windyboard mast - designed to curve from half way up) pole upto 15m long, diameter at base 10cm tappering to .5 cm at tip, to say a force eight gale.
Any thoughts or possible contacts woulb be really appreciated!
Cheers
Adrian Davis
WA
877 posts
an art exhibition???? or science
WA
9106 posts
i reckon about 8.3345 rec should be about right.
But thats only if you consider the convex of the apex which is directly opposite to the exposure of the surface that could be potentiating the force beneath the air when submerged to 3 quarters.
I also believe that it depends on a rider, if its hardie its off the scale and all calculations are out the window.
1116 posts
P Rel
Obesity is a disorder and not to be made fun of on public forums, such as this one, OK so I eat one too many hamburgers an hour.....
Let's get back to the topic and help this poor fellow.......
Polystryrene foam has a greater bouyancy in salt water usually about 8%, over fresh water. Given that one cubic metre of display grade poly will carry probably above it's volume divided by it's density it will be still 8 % above neutral bouyancy, however when taking into acount displacment, you need to square the weight and divide by the square root of the volume. Given this volume block would like be approx 75% of the block submerged, then you need to subract 25 percent in your equations, then multiply by 75%, adding the 25% subtracted then squaring the diameter of the hypotenuse, of the cubic figure!
OH Phuck, I forgot its a cubic measurement we need. Don't square the sums, Cube them, then ensure the division is a cubed division. I'm all confused now.......... Was that cubic measurement adjusted for weight coz weight needs to be considered here as well, any calculation must have weight subtracted as well.
Hopefully once you've got the figures for this ratio you can then get on with the design.
Re: expertise in keel design - I did assist in the winged keel design for Australia 2 so might be of help!
BTW are you prepared to pay for any of this advice or are you expecting to get it for free?
Coz My dear friend you usually get what you pay for.........
WA
20 posts
I always thought the answer to everything was 42
coz if it was you need to contact NASA
