Fluid Flow Questions

Can't tell what that is a picture of.

There seem to be three temperatures - T1 seems to be between some rectangles, T2 seems to be to one side (presumably there is a temperature gradient of some kind in there? There is an intermediate T3 which does not seem to appear anywhere.

There is a label "gas flow" apparently along a line.

You need a clearer diagram.

 

What are the four blocks - cutaway of a system of pipes?
Does the interior also have gas in it or is it evacuated?
Is the system in equilibrium before the new gas is injected?

Gas already in the system will want to move away from the center (T1), but there will be some flow inwards. New gas injected at the place specified would tend to move with the ambient flow.

It "up" on the diagram is actually upwards, then the gas at T1 will prefer to exit through the top. Cool air comes in the bottom and the sides.

 

Well then I cannot be precise.

If I imagine two plates with a hole in the middle, molten metal flows through the hole so no air can get in through the top or bottom, and the edges are open to the air - then some parts of the edge will have inflowing air and others outflowing with the exact places constantly changing unless the geometry is small enough for micro-cells to form.

What do you need to know for?

 

Nope - not at all clear.
You've just added a hopper - in the overhead view it looks not like there is a circular chamber around the hole the metal pours through - or maybe it's just a groove between two closely fitting plates. The angle that the gas is being injected suggests a vortex is added to whatever other motion their may be.

I have no idea. You'll just have to work it out from first principles... the hotter gas will be moving faster so it will tend to move away from the hot area ... cooler gas will try to move in to replace it.

What are you hoping will happen? What is injecting the gas close to a column of molten metal supposed to achieve?

Bottom line though is that I am only here to help you understand (and phrase) your problems better so that you will know how to solve them. I am prepared to do that for free you understand... up to a point. If you are unwilling to tell me about your problem then I cannot help you.

 

Not that simple.

In general - hot gas molecules move faster than cold ones so they tend to move away from the hot place. But that would reduce the pressure, sucking more gas in - which tends to be the cold gas. This van be chaotic (in the technical sense) but there are situations where you get circulation happening - which is called a cell.

Hot gas is less dense (because faster) so it tends to rise.

Think about how thunderheads form, or thermals, or how high explosive has a characteristic mushroom cloud.

All this is for some kind of open space - you can get gas to move in a narrow pipe fairly regularly - it does so by expanding from the hot end of the pipe though you'd usually pump it.

If the hot air escapes through a hole at the top of a chamber and you let cold air in through the bottom (it gets sucked in) you have a chimney effect.

A bunsen burner sucks air in through holes in the bottom of a pipe which has gas flowing through it under pressure. This is why I guessed that the injected gas will go with the ambient flow.

It is not easy.

lets see ... argon + molten metal going through holes: casting?

 

In investment casting or a sand mold I would think that air could flow thorough the mold. Like Simon I am having trouble interpreting your drawings.

I have done a fair amount of Aluminium investment casting.