Hi there,
I think the camber line is theoretical rather than an actual structure (please correct me if I'm wrong though). for an aerofoil with no camber at 0 angle of incidence the pressures are equal and hence no lift. For a cambered aerofoil, the pressures and lift depend on the camber and...
Hi, I mean when they are flowing through pipework as a gas. One of them has to be overpressurized with nitrogen to help it flow whereas the other flows easily through pipework.
Hi,
A quick question, I'm looking at two fire suppressant gasses, HFC 125 and HFC 227ea. One of which flows much better than the other. I was wondering which is the main property that affects the flow of the gas ? I was thinking vapour pressure but am probably wrong ! if you want to look into...
Hi Again, sorry for not replying sooner. my only access to the internet is at work and hence I can't use it too often !
I think a belly pan will be a good idea, it will result in a significant reduction in drag. However, you can't avoid turbulence under the car due to the road surface and...
Hi,
I'm probably being a thicko here but what exactly is a boat tail ?!
Regarding a diffuser, yes it will increase drag because you're producing a wider wake. however you can significantly reduce drag by making the underside of the car smoother. having a venturi underneach the car speeds the...
A lip on the mirror could increase or decrease drag depending on how you position it, ether way it's probably quite insignificant and the side and front of the car may also effect the airflow in the area behind the mirror.
What type of racing are you looking at ?? if you are looking at less...
Done (I think) ! - it hasn't taken me this lomg to work it out by the way, I've only just started looking at it again !
I've worked out the pressure required in the gas side of the tank using F=PxA + pressure on other side of piston. it turned out to be a tiny increase on that of the other...
You're right, but I've already worked out the speed of the piston using the desired flow rate of water at a given pressure. The pressure is in the water side of the system so basically, I'm working out the required gas pressure.
I've posted another thread previously that explains what the...
The pressure is a constant 6 bar. Basically, it's gas on one side of the piston and water on the other. The gas is used to push the water out of the system.
Not a prob any more, I'm just going to have to assume an acceleration using the speed I require.
I guess it's just a simple F=ma +...
Thanks for that,
I've checked wiht the piston ring manufacturer and can discount the friction, so thats one less thing to think about.
Obviously the balancing force is now 6 bar, however, I'm not sure how to find the force needed to move it at a given speed. Is there a calculation I can use...
Hi Again, I thought I'd better start a new thread.
I need to find the force required to push a piston along a tank.
I know the force atcing on the opposite side (the other side is pressurised at around 6 bar) and will find out the friction coefficient of the piston rings on the tank surface...
Hi There,
A quick question, In the past I have used CFD to look at styling on cars, however I don't have CFD any more.
Do you think it would be possible to get a basic idea of how effective aerodynamic aids are at differing speeds without the use of CFD ?
Hi there,
You're right, I am over complicating things, I always do !!
It's not actually a pump that I require. I'm designing a piston, pushing a liquid out of a tank using an increase in gas pressure in a chamber behind the piston. I've just realised it is very easy to do !
The only thing...
Are you sure about this ? according to Bernnoulli's equation you get an increase in flow rate and a drop in pressure at a pipe contraction (off the top of my head !)
Baring mind that there is a large contraction at the entrance to the pipe and also another a bit further along the pipe, I thought...
Hi Again,
I worked out the head loss using Hazen-Williams for some branches of the system, and because the system is quite small it turns out the loss is negligible. So back to square one :(
What I am doing now is starting from the tank end. Basically there is a pipe in the tank which is...
or 2 hours for a recently graduated engineer, especially after a year out of the industry !!
Thanks for the advice everyone, I will have a look tonight and then let you know how it went.
Carla
Hi Quark,
The nozzles are ones that we already use, and vary (generally between 4 types of nozzle)depending upon the application. What I am going to do is begin by looking at several applications and specifying the nozzles before doing any calculations.
Basically, I don't want to make any...
Thanks for the advice.
Yes it is a pipe network (fairly basic) that branches out to various different nozzles. Luckily the branches will be more or less the same length and I have the info on pressure losses in the nozzles, and I think I even have info on the pipe and connectors.
Right, I'm...
Iha, I've just read your reply. Please ignore my previous post.
You're right, I do want to find a tank pressure that would be sufficient to supply the nozzles.
I'm not familiar with Hazen Williams so I will get reading over the weekend. Thanks for that
Hi, and thanks for the advice, I'm actually looking at a catalogue that is quite similar to the link.
For the nozzles I am using, the flow rate does increase as pressure increases. I'm looking at a table showing flow/pressure info at the mo.
Hang on a min, I think I'm being stupid here, so...
