How does siphoning petrol work

Now, siphoning gas through this small tube by gravity is slow and can take up to eight minutes for a gallon of gas. If you can find a small hose with a hand pump like this one , it can go much faster. You may want to carry a larger hose for vehicles that will accept it. Just remember that stealing gas is illegal and should be avoided.

Most every reader of One Second After is convinced that virtually every vehicle on the road will suddenly stall and be incapacitated forever.

Arthur T. The rest may experience a slight glitch and then resume running. With millions of vehicles stranded on every type of road, bridge, and tunnel imaginable, transportation would still be difficult. Nice article. I have some tubing from a refrigerator we bought a while back. Think I will try it.

Nice Disclaimer. My fuel pump went out right after I filled up my tank. In order for me to replace the pump, I have to drop the fuel tank, which meant I had to drain the tank first.

After trying a garden hose, I took your suggestion. The important part is cutting the end to a sharp point. Thanks for the info! Hmm, that was interesting. You could just walk away and come back later. Having a longer hose, and putting the gas can all the way on the ground, would help because it would give more gravity to the situation.

Oh, and the hardware store is full of cheap hoses of all different diameters. I just bought one for my aquarium protein skimmer. The old one got aged and stiff. Though the experience of having gas stolen from my gas tank while I had the vehicle in storage, I found out that there is a connection to the gas tank of a Odyssey that can be disconnected to drain the gas tank.

How did you drain it? Does it have a capless gas tank, thos have anti siphon filters. The pipe that connect to the fuel injector is easy to disconnect safely. You need to put the container close, which mean above the level in the gas tank. Now first off what is a siphon? Well a siphon is a tube that I stick into a pool of water or some other fluid and then pull up out of the top and then I have the other end of that tube lower down closer to the earth than the tube in the water.

And so what happens is, if I can initiate a flow, if I can get that fluid flowing up through there, so that it comes over the top and then falls down it's going to pull the rest of the fluid with it. And so people will use this to empty pools and sometimes to empty gas tanks but it is a very important physical process that uses Bernoulli's Principle.

Now what's Torricelli's law? Torricelli's law is named after the Italian physicist Evangelista Torricelli who derived it in and what he said was that if you take a container of liquid and you've got a hole in the bottom of it, then the liquid will flow out of that hole at the same speed that it would move at if would just take the liquid from the top and drop it. Now the direction is going to be different, if I take liquid from the top and I drop it, it's going to be going down.

But if I've got a tank and I poke a hole on the side of it the liquid is going to be going horizontally is going to be going over, but the speed is the same and that's Torricelli's law. Alright so let's go ahead and look at a problem involving a siphon and we'll see where these Torricelli stuff comes up and also where Bernoulli comes up it'll come up all the time. Alright so let's look at this siphon problem right here, I've got a pool of water, we'll just take it to be water, it could be any other fluid though and I've got my hose I've put it one end of the hose at point c down at the bottom of the tank of water which is 5 meters below the surface, then I pull it up and out.

It's got to go over the edge of the container and that's a point b which is 2 meters above the surface and then I bring down the other end to point d which is 8 meters below the surface. Now the reason that the siphon is going to work is because the fluid is going to come out here at a lower point in the gravitational field that the earth than here where it came in.

Alright and so that what's going to give me the energy that I need to get over this potential barrier. Now if I'm just going to leave that thing sitting here, it's not going to do anything. I got to initiate the flow first, alright and the way that I do that is I have to put a pump over here and pump out some of the air at point d or I'll just use my mouth and I suck on it real quick to pull the liquid up to point b so that it realizes that it can then fall down.

And then once I've initiated that flow I just stand back and the whole container will empty by itself. Alright now how are we going to determine the actual numbers associated with this problem? Well it turns out that Bernoulli's principle is exactly what we need. Bernoulli's principle let's, I've written it over here, now I've written it in the case of constant density which is fine with water because water is almost incompressible. Very, very difficult to change the density of water you need a lot of pressure to do that and that's something we're not going to have here.

So we've got pressure plus density times acceleration due to gravity times height plus one half density speed squared is a constant. Now we can interpret this in the exactly the same way as conservation of energy. Pressure represents a sort of potential energy associated with the fluid itself, rho gh represents gravitational potential energy just like mgh except I divided by the volume which is essentially what we always do with fluids.

One half rho d squared is just like one half mv squared that's kinetic energy. So this is just conservation of energy, now as with essentially all conservation of energy problems the way we're going to approach this is by finding 2 different points. And the other point which contains information that I want to know, and then I just say okay they got to be the same.

And then I'll solve the equation and get everything I want. Alright so the most complicated part of this problem essentially any part of it, is setting it up, trying to decide which parts we want to use and what we know about those parts. So what I want to do is just kind of show you how to set it up and I'll give you the answers but I'm going to go through a full detailed calculation. Alright, so let's go ahead to part a, part a asks us for the gauge pressure to initiate the flow.

Now remember gauge pressure is pressure minus atmospheric pressure. Now we said that in order to initiate flow we're going to have to suck on the end of this hose at point d. So that means that the pressure up here at point b is going to have to be less than atmospheric, so the gauge pressure will be negative.

Alright now when we've got flow initiated the water has got to come up to this point, just right at that point. It won't be moving yet but it's going to get right up to that point. And I want to know the pressure right here okay.

So I need 2 different points in this fluid flow to apply Bernoulli's principle to. When the air conditioner in your Toyota Sienna starts blowing hot air, you likely have a freon leak. Most refrigerants include a leak sealer that will seal small leaks in addition to filling the Ra refrigerant. These are pretty widely sold. How to add freon to your Toyota Sienna: hook up the can of refrigerant likely ra to the low pressure port.

When your compressor kicks on, add freon to the correct pressure. In addition to cooling, freon lubricates the compressor when it runs.