why are the..........

[celica man]

big oil tankers all round? is it because the center of gravity is all weird because it is liquid? because i would think that there is more mass in a square shape which means it could carry more product.....ie. milk, gas, oil etc



ROUND


http://www.agdepot.com/images/tanker.jpg



square



http://www.agdepot.com/images/truck2.jpg

[celica man]

b20civic should know

[stu]

It probably has to do with the way that the liquid moves around. With a curved wall, the oil or whatever can climb the wall if it's below the mid point, or slide up and then splash down on top of itself if it's pretty full. Where as if it was just flat, it'd just push against the side of the truck. Also, it might be a standard just so you know it's liquid just by looking at it. That, or the only other thing I could think of was that trucks are only allowed to carry a certain amount of fluid at a time for driveablity reasons, so they might as well not waste the material making a bigger, square tank. But that's just what I would guess.


EDIT: On thing that confuses me though, is that I know driving with liquid can make operating the truck difficult, but I remember learning in physics that nothing that goes on inside of something that is moving has any effect on the vehicle itself. IE, if everyone in a bus ran and jumpkicked the back wall while driving, the bus wouldn't slow down.

[Skaterkid]

Actually for the same amount of material a sphere has more volume. Just do the math.

[exciv2000]

I think trucks are stupid. And of course I'm just saying this cause I know B20civic is going throw an ape shit fit. ;)

Added to which I think stu did a pretty good job of explaining the reasons. From what I've heard I can pretty much vouch for his answers. Additionally, it's easier to seal a cylinder than it is a rectangle.

[celica man]

Actually for the same amount of material a sphere has more volume. Just do the math.


i dont think so.....i could be wrong though

http://www.deuxpoissons.com/Collections/Herman%20Hermsen/broches%20square%20circle%20B.gif

[tsitim]

I think due to the amount it holds and also the fact that liquid moves either back and forth or side to side. Some tankers have a metal plate across the center which keeps it from moving to much. Just think if you take a turn to wide in a trailer the liquid would not move as easily as it would in a tank. ;)

[stu]

Jose, I bet if you stretched that material out into a line, the square would be longer, with the same amount of material the sphere is bigger.

[HONDA GHANDI]

There are baffles in the tanker trucks to keep slosh to a minimum. I drove a ranch truck with a small (800 gallon) tank on the back of it full of water. Step ont eh brakes really hard and the truck would lurch forward when the fluid hit the front of the tank. Very hard to drive. Over the road trucks have weight restrictions so if the tank was the same size as freight haulers they would probably be grossly overweight.

[Skaterkid]

Do the math man, your eyes decieve you.

[tsitim]

There are baffles in the tanker trucks to keep slosh to a minimum. I drove a ranch truck with a small (800 gallon) tank on the back of it full of water. Step ont eh brakes really hard and the truck would lurch forward when the fluid hit the front of the tank. Very hard to drive. Over the road trucks have weight restrictions so if the tank was the same size as freight haulers they would probably be grossly overweight.
baffles! thats the word ;)

[DrJones]

Just to settle it... Volume in this case is simply the area of a cross section, multiplied times the length of the truck. Since the length is the same in both cases, we can ignore it and just compare the areas.

A square with side length r has an area of r*r, and a perimiter of 4r.

A circle with radius r, has an area of pi * r * r, and a perimiter of 2 * pi * r.

Compare the ratios.

In the square's case, the ratio of area to perimiter in terms of the legnth of one side r, is (r*r)/(4r), or simplifies to r/4.

For the circle, the ratio of area to perimiter in terms of the radius r, is (pi*r*r)/(2*pi*r). Simplified gives r/2.

The circle has a higher ratio, meaning that for a given change in size of the value r, your area increases more than it would than with the square.

Lets try an example, given a perimiter of 10 in both cases, the square (r=10/4) has area (10/4) * (10/4) or 6.25.

The circle (r=5/pi) has area pi * (5/pi) * (5/pi). This simplifies to 5 * 5/pi, or 7.95774....

As you can see, the circle gives you more area for a given perimiter. Thus the circular tank would have more volume, given the same area, than a square one would.

[saabracr]

The cylidrical tank is safer for it has fewer seams and they are at much larger angles to each other, as compared to 90deg corners. A seam at a corner like that will split more easily when the force of eleventy billion gallons hits it in a tight maneuver.

[stu]

Oh yeah, also, the cylinder is stronger, think of arches, keystones, and trying to break an egg in your hand.

[B20civic]

how did i miss this old ass post?

van trailers,a re used mainly for any goods.

tankers, there are many different varitys.

-gas tankers, are usually ovals tankers, and have seperate 'walls' in them (for different octanes/diesel)

-food products are a smooth bore inner, usually round, or oval. (smooth bore meaninig nothing inside)

-oil/other chemicals usually use a 'baffled' inner design, it has baffled walls, to cut down on the front to back movement of the liquid.


tankers are the hardest to pull. you have the gravity issues, and in a non baffled tanker, upon braking you have all that weight rushing forward making stopping difficult ;)
its actually an easy endorsment to acquire :o