Pics isa must if yer fitting shinny bits. :cool:

You’d have to look at the bits of the forum where the proper landies wot don’t leak and rust are… 😉

New subframe in yesterday…

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That IS it but it assumes constant temperature.
If you heat a gas in a constant volume, the pressure of the gas inside it will rise in direct proportion to the temparature.
Which is why a piston in a car engine flies down (i.e. volume increases) when the mixture explodes. The volume increases as the temperature and therefore the pressure increases.
I believe the equation with all three in it is
P1V1/T1 = P2V2/T2
But Boyles law considers constant temp :vb-confused2:
Check out your back up, Wiki or any other and you will see temp is always mentioned as "constant".

J
 
but its got three angles, must be a triangle? If not, the only triangle in the puzzle is the big one. And that's an easy sum to do - 1/2 base x height.
Yes and maybe that's the trick of the brain. It says Triangle and colours it Orange then colours a little bit that is in no way connected to the question.

The only triangle I see is the complete outline triangle ;).

This is all a nefarious @Hippo Plot, and why I asked him to post the answer the next day.

J
 
But Boyles law considers constant temp :vb-confused2:
Check out your back up, Wiki or any other and you will see temp is always mentioned as "constant".

J
I don't understand your comment, the first thing I said in the post was "That IS it (i.e. Boyle's Law) but it assumes constant temperature." So I was agreeing wiv you!

I then just went on to explain how the full gas PVT equations work and allow you to consider what happens when temperature changes. I agree the name of the equation, P1V1/T1 = P2V2/T2 isn't Boyle's law but nor is it it Charles' s law neeva. In fact I couldn't find a name for it beyond "Gas equations" :rolleyes:;):)
 
I am now waiting for Prof Wimblowdriver to explain to me, and any others interested, how he solved the surface area of the ickle sort of triangle.
For a start I'd love to know why the lengths two sides of the triangle were given in such a way.
I haven't given it a huge amount of thort. I'm like the lazy boy who gets to class a fraction early and copies the swot's HW!

I knew a very attractive (actually smoking hot) first year French degree student who used to panic the day of her grammar class and brought her HW for me to "help" her with just before she ran off to it. I was in my 4th year by then so did it pretty quickly, Well I felt I kind of owed it her as we had ... history.
(Oops, must remember this isn't AG!;););););))
 
I don't understand your comment, the first thing I said in the post was "That IS it (i.e. Boyle's Law) but it assumes constant temperature." So I was agreeing wiv you!

I then just went on to explain how the full gas PVT equations work and allow you to consider what happens when temperature changes. I agree the name of the equation, P1V1/T1 = P2V2/T2 isn't Boyle's law but nor is it it Charles' s law neeva. In fact I couldn't find a name for it beyond "Gas equations" :rolleyes:;):)

Then don't add a "T" in Boyles law.

Its thermal expansion, but is difficult to narrow down as the volumes changes , so pressure changes.

He should have just followed simple instruction's and pricked it :D.

We have mains supplied hot water tanks, they heat water but don't explode because they have calculated the length of the outlet to leave an air space to allow for expansion due to heat, they don't expand. Oh and they are stronger than a plastic bag ;).

J

J
 
Then don't add a "T" in Boyles law.

Its thermal expansion, but is difficult to narrow down as the volumes changes , so pressure changes.

He should have just followed simple instruction's and pricked it :D.

We have mains supplied hot water tanks, they heat water but don't explode because they have calculated the length of the outlet to leave an air space to allow for expansion due to heat, they don't expand. Oh and they are stronger than a plastic bag ;).

J

J
Do you not have one of those expansion chamber type things? We do, and ours is heated by solar, as I think you will remember.
Like the white thing in this pic.
1728311710302.png

We do also have mains that can heat it when there isn't enough sun.
 
Do you not have one of those expansion chamber type things? We do, and ours is heated by solar, as I think you will remember.
Like the white thing in this pic.
View attachment 327625
We do also have mains that can heat it when there isn't enough sun.

Nope.
We have an expansion "ball" on the solar (closed system). But the hot water tank outlet comes from the top, but not at the top so allows for expansion of the water due to heat. Just like the "ball" I.E has an air space closed system.

But your pic shows a closed system tank so that 250L(?) tank needs expansion into the "ball"
Our 500L buffer tank (heated by solar but separate water) is ATM (open vented to tank)

J
 
I spent some time making a jig for a mate. The requirement is to accurately locate and drill holes for bolt heads so that they can be used as "drive-dogs". Easiest way I could think of was to use an actual disc rotor to drill through and locate it on a central 6mm bolt/pin.

A simple job and I can weld the bits together tomorrow sometime.
It will go with the other bits I have made for the same job. That was a set of bearing housings and an alignment jig to make sure everything was coaxially aligned when they were mounted to the drive plate.

Boring to you all I am sure, but a bit of escape and "fun" for me. :D


1728313962369.png
 
Nope.
We have an expansion "ball" on the solar (closed system). But the hot water tank outlet comes from the top, but not at the top so allows for expansion of the water due to heat. Just like the "ball" I.E has an air space closed system.

But your pic shows a closed system tank so that 250L(?) tank needs expansion into the "ball"
Our 500L buffer tank (heated by solar but separate water) is ATM (open vented to tank)

J
Is it a goal to be largely "off-grid" and independent?
 
Is it a goal to be largely "off-grid" and independent?
Sort of, Not entirely off grid but hate to waste the sunshine available.

The 500L tank is a “night storage” from the wood burner for the underfloor heating +hot water (in the winter) the solar heats this in the summer, which then heats the hot water (in the summer).
We have electric backup for the hot water, but if we have a power cut in the winter we have no heating, cos the wood burner is water jacket so would boil because we couldn’t run the central heating pumps,So hence the solar electric and battery backup.
All based on winter worst case. Summer we are overflowing with electricity and hot water.

It’s great when you can start with a clean slate :).

J
 

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