On 17/06/2020 15:18, Andrew wrote:
On 17/06/2020 14:57, Jim GM4DHJ ... wrote:
On 14/06/2020 19:44, harry wrote:
On Sunday, 14 June 2020 18:48:04 UTC+1, Duncan DiSaudelliÂ* wrote:
Hello

Our house has some single and double radiators, probably 1980s vintage,
fed from a conventional gas fired boiler.

Except for the fact that they might be full of rust and sludge etc., is
there anything radically different about modern designs which would
make
them more efficient?

In other words, if they are still of sound construction, is there much
point in replacing them?

Might it be just as sensible to get the system (and thus the radiators)
power-flushed?

DDS

Radiators do not have an efficiency.
To find if they are full of sludge, run your hand over them and see
if there's any cold spots. (Invariably at the bottom.)
As long as they keep the place warm and aren't leaking leave them alone.

You might consider thermostatic valve.
If already fitted,make sure they're working.

that's a waste of time with a wummin in the house they just can't grab
the concept of turning a TVR down...all mine are screwed up due to her
so I retaliate by having the boiler thermostat at 17 dec C

That's a bit extreme for Scotland isn't it ?. Even in Sussex I would
feel cold at 17C.
tough.....serves her right for turning all the TVRs up......

On 17/06/2020 14:15, Dave Plowman (News) wrote:
In article ,
wrote:
If an engineer isn't able to design a silent fan they had better stay
out of that business.

Would that be 100% silent? ;-)

They must be mythical, since I have never heard a silent fan! :-)


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On Thu, 18 Jun 2020 00:25:47 +0100, John Rumm wrote:

On 17/06/2020 14:15, Dave Plowman (News) wrote:
In article ,
wrote:
If an engineer isn't able to design a silent fan they had better stay
out of that business.

Would that be 100% silent? ;-)

They must be mythical, since I have never heard a silent fan! :-)

A silent fan that can be heard would be noisesome.
--
Peter.
The gods will stay away
whilst religions hold sway

On 17/06/2020 12:37:23, wrote:
On Tuesday, 16 June 2020 22:49:26 UTC+1, Fredxx wrote:

You're very much on your own when it comes to your definition of
radiator efficiency. This should help give you an indication of your
losing argument:
https://lmgtfy.com/?q=efficiency+of+a+radiator&s=l

The application of efficiency to a radiator isn't just heat out / heat
in. Best get used to it or be forever stuck in the past and viewed as
senile.

come back when you've got a fact to offer us.

The fact is some of us have moved with the times and accept new or a
change of meaning to a word.

It's another fact others are in denial, suffering from senility.

On 17/06/2020 12:48:21, wrote:
On Wednesday, 17 June 2020 04:45:08 UTC+1, RJH wrote:
On 16 Jun 2020 at 22:10:25 BST, tabbypurr wrote:
On Tuesday, 16 June 2020 19:55:22 UTC+1, Dave Liquorice wrote:
On Tue, 16 Jun 2020 09:53:42 -0700 (PDT), tabbypurr wrote:

I suspect fanned rads will make a comeback some day once people realise
they can have a much smaller rad without all the fan noise of the old
ones.

s/fanned/finned/ ?

Not sure what that means, but they do tend to go together. A fan with a flat
panel works for a diy job but is not optimal design costwise for a new
product.

All you need for a fanned rad to work, take up way less space and be much
preferred is silence,

I can see how you get quiet for a reasonable amount

http://openecohomes.org/diy-fanned-radiator/

But silent?

and that's not a challenge.

For you, maybe :-)

If an engineer isn't able to design a silent fan they had better stay out of that business.

Moving any volume of air around inherently creates noise. An engineer
would know this, otherwise they best stay out of that business.

Fredxx wrote:
On 17/06/2020 12:48:21, wrote:
On Wednesday, 17 June 2020 04:45:08 UTC+1, RJH wrote:
On 16 Jun 2020 at 22:10:25 BST, tabbypurr wrote:
On Tuesday, 16 June 2020 19:55:22 UTC+1, Dave Liquorice wrote:
On Tue, 16 Jun 2020 09:53:42 -0700 (PDT), tabbypurr wrote:

I suspect fanned rads will make a comeback some day once people
realise
they can have a much smaller rad without all the fan noise of the old
ones.

s/fanned/finned/ ?

Not sure what that means, but they do tend to go together. A fan
with a flat
panel works for a diy job but is not optimal design costwise for a new
product.

All you need for a fanned rad to work, take up way less space and be
much
preferred is silence,

I can see how you get quiet for a reasonable amount

http://openecohomes.org/diy-fanned-radiator/

But silent?

and that's not a challenge.

For you, maybe :-)

If an engineer isn't able to design a silent fan they had better stay
out of that business.

Moving any volume of air around inherently creates noise. An engineer
would know this, otherwise they best stay out of that business.

In principle, the convection you're relying on now to distribute
the heat from the radiator, that's moving air, and it's pretty
quiet. Suggesting human hearing is not infinitely sensitive.

If you make the radiator large enough, you should be able to
match the fan-driven performance. With a large enough radiator,
the exhaust water temp will be the same as the room air temp.
That should be the limit.

Paul

On Tue, 16 Jun 2020 20:47:41 +0100 (BST), in uk.d-i-y "Dave Liquorice" wrote:

On Tue, 16 Jun 2020 16:02:12 +0100, Phil Addison wrote:

The system is highly complex ie not just a pair of pipes
that goes from one rad to the next. There are rads on long spurs,
with different lenghts/bends for the pipes, spurs with rads
connected
overlapping and rad acroos the main pair.

I don't see how that invalidates the procedure, ...

But note that in some cases this will be impossible due to bad design of
the pipework ...

Perzackerly.

Thermal imaging camera allows you to see how much flow is (or
isn't!)
going through a rad by the size of the rising hot water column
from
the inlet. This also responds very quickly to any changes.

I haven't had the chance to use an IR camera, and can see it would be
helpful to see the immediate effect of a small turn of the valve, but I
emphasise that you don't want full flow in all the rads.

Maybe not but it enables you to setup an even starting point
relatively quickly and painlessly.

A common misconception is that increasing flow-resistance will make a
radiator cooler. Not necessarily: for a rad already getting as much heat
as it can dissipate, closing its valve a bit just makes the pump
increase its pressure so that rads further away get more flow.

No the rads with a lower flow resistance get more flow, they may or
may not be further away.

Yes, "rads further away" wasn't a good choice of wording. In fact ALL the other rads get a bit more flow because the total system resistance increases when you restrict flow in any radiator, thus driving the pump a bit further up its pressure/flow curve. This in turn causes a bit more flow in all the other rads.

Phil

On 18/06/2020 22:12, Paul wrote:
Fredxx wrote:
On 17/06/2020 12:48:21, wrote:
On Wednesday, 17 June 2020 04:45:08 UTC+1, RJHÂ* wrote:
On 16 Jun 2020 at 22:10:25 BST, tabbypurr wrote:
On Tuesday, 16 June 2020 19:55:22 UTC+1, Dave LiquoriceÂ* wrote:
On Tue, 16 Jun 2020 09:53:42 -0700 (PDT), tabbypurr wrote:

I suspect fanned rads will make a comeback some day once people
realise
they can have a much smaller rad without all the fan noise of the
old
ones.

s/fanned/finned/Â*Â*Â* ?

Not sure what that means, but they do tend to go together. A fan
with a flat
panel works for a diy job but is not optimal design costwise for a new
product.

All you need for a fanned rad to work, take up way less space and
be much
preferred is silence,

I can see how you get quiet for a reasonable amount

http://openecohomes.org/diy-fanned-radiator/

But silent?

and that's not a challenge.

For you, maybe :-)

If an engineer isn't able to design a silent fan they had better stay
out of that business.

Moving any volume of air around inherently creates noise. An engineer
would know this, otherwise they best stay out of that business.

In principle, the convection you're relying on now to distribute
the heat from the radiator, that's moving air, and it's pretty
quiet. Suggesting human hearing is not infinitely sensitive.

If you make the radiator large enough, you should be able to
match the fan-driven performance. With a large enough radiator,
the exhaust water temp will be the same as the room air temp.
That should be the limit.

and also not necessarily ideal from the system point of view since the
boiler probably can't lift the water temperature from ambient room air
temperature to target flow temperature in a single pass.


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On 18/06/2020 22:12:30, Paul wrote:
Fredxx wrote:
On 17/06/2020 12:48:21, wrote:
On Wednesday, 17 June 2020 04:45:08 UTC+1, RJHÂ* wrote:
On 16 Jun 2020 at 22:10:25 BST, tabbypurr wrote:
On Tuesday, 16 June 2020 19:55:22 UTC+1, Dave LiquoriceÂ* wrote:
On Tue, 16 Jun 2020 09:53:42 -0700 (PDT), tabbypurr wrote:

I suspect fanned rads will make a comeback some day once people
realise
they can have a much smaller rad without all the fan noise of the
old
ones.

s/fanned/finned/Â*Â*Â* ?

Not sure what that means, but they do tend to go together. A fan
with a flat
panel works for a diy job but is not optimal design costwise for a new
product.

All you need for a fanned rad to work, take up way less space and
be much
preferred is silence,

I can see how you get quiet for a reasonable amount

http://openecohomes.org/diy-fanned-radiator/

But silent?

and that's not a challenge.

For you, maybe :-)

If an engineer isn't able to design a silent fan they had better stay
out of that business.

Moving any volume of air around inherently creates noise. An engineer
would know this, otherwise they best stay out of that business.

In principle, the convection you're relying on now to distribute
the heat from the radiator

snip

This subthread was discussing the use of a 'silent' fan. I'm quite aware
that you might expect air currents formed by convection from a domestic
radiator to be inaudible.

On 17/06/2020 12:38, wrote:
Feel free to tell us where the inefficiency is in an oil filled radiator. (I think we can assume it doesn't get so hot as to glow.)

Of course they glow. Pretty much everything glows.

Just not necessarily in the visible spectrum. (And IIRC glass reflects
most long-wave infrared to help keep it in the house.)

Andy

On Wednesday, 17 June 2020 14:15:48 UTC+1, Dave Plowman (News) wrote:
In article ,
tabbypurr wrote:

If an engineer isn't able to design a silent fan they had better stay
out of that business.

Would that be 100% silent? ;-)

First silent fan I made I could hear nothing at all with my ear as close as possible to the spinny bit in a silent room. I'd say that's good enough once inside a box. Naturally you'll have your own ideas.


NT

On Wednesday, 17 June 2020 14:15:48 UTC+1, Dave Plowman (News) wrote:
In article ,
tabbypurr wrote:
On Wednesday, 17 June 2020 00:16:18 UTC+1, Dave Plowman (News) wrote:
In article ,
tabbypurr wrote:
On Tuesday, 16 June 2020 18:47:11 UTC+1, Dave Plowman (News) wrote:
In article ,
tabbypurr wrote:
Nothing is ever 100% efficient.

incorrect. Another example is an electric convector heater.

Not so either. A standard convector heater element produces light,
although likely outside the visible spectrum.

Don't think I've ever seen an oil filled radiator style heater that
emits light. As for bare element ones, some do some don't.

If it isn't visible light, you won't see it.

But it's the case that simply nothing is 100% efficient. May come very
close, though.

Feel free to tell us where the inefficiency is in an oil filled
radiator. (I think we can assume it doesn't get so hot as to glow.)

Have it your own way. Some things are exactly 100% efficient. I take it
you work in advertising?

So you've no idea where any inefficiency occurs in that radiator, but still want to make silly comments. Mmkay.

On Wednesday, 17 June 2020 14:55:51 UTC+1, Andrew wrote:
On 14/06/2020 23:58, tabbypurr wrote:

All rads are 100% efficient. It's not as if some of the heat can be lost outdoors from the rad.


NT


If mounted on an external uninsulated wall, then there must be
additional conduction losses via the section of wall
immediately behind the rad.

Yup. But it's not the rad being inefficient.

Isn't that why putting insulated foil-stuff behind the rad
was one of the 'energy saving' tricks that people used to do
in the late 70's and 80's ?.

That blocks loss from heated air, but not from the steel mountings.


NT

On Thursday, 18 June 2020 21:31:49 UTC+1, Fredxx wrote:
On 17/06/2020 12:37:23, tabbypurr wrote:
On Tuesday, 16 June 2020 22:49:26 UTC+1, Fredxx wrote:

You're very much on your own when it comes to your definition of
radiator efficiency. This should help give you an indication of your
losing argument:
https://lmgtfy.com/?q=efficiency+of+a+radiator&s=l

The application of efficiency to a radiator isn't just heat out / heat
in. Best get used to it or be forever stuck in the past and viewed as
senile.

come back when you've got a fact to offer us.

The fact is some of us have moved with the times and accept new or a
change of meaning to a word.

It's another fact others are in denial, suffering from senility.

The definition of energy efficiency has not changed. Nor has the looser usage of the word efficiency in other contexts. Some people believe anything.


NT

On Thursday, 18 June 2020 21:32:00 UTC+1, Fredxx wrote:
On 17/06/2020 12:48:21, tabbypurr wrote:
On Wednesday, 17 June 2020 04:45:08 UTC+1, RJH wrote:
On 16 Jun 2020 at 22:10:25 BST, tabbypurr wrote:
On Tuesday, 16 June 2020 19:55:22 UTC+1, Dave Liquorice wrote:
On Tue, 16 Jun 2020 09:53:42 -0700 (PDT), tabbypurr wrote:

I suspect fanned rads will make a comeback some day once people realise
they can have a much smaller rad without all the fan noise of the old
ones.

s/fanned/finned/ ?

Not sure what that means, but they do tend to go together. A fan with a flat
panel works for a diy job but is not optimal design costwise for a new
product.

All you need for a fanned rad to work, take up way less space and be much
preferred is silence,

I can see how you get quiet for a reasonable amount

http://openecohomes.org/diy-fanned-radiator/

But silent?

and that's not a challenge.

For you, maybe :-)

If an engineer isn't able to design a silent fan they had better stay out of that business.

Moving any volume of air around inherently creates noise. An engineer
would know this, otherwise they best stay out of that business.

I take it you're not an engineer then. Or an ignorant one.

Hint: try turning a desktop fan round by finger & see how noisy it is. No wind noise.


NT

On Thursday, 18 June 2020 22:12:30 UTC+1, Paul wrote:
Fredxx wrote:
On 17/06/2020 12:48:21, tabbypurr wrote:
On Wednesday, 17 June 2020 04:45:08 UTC+1, RJH wrote:
On 16 Jun 2020 at 22:10:25 BST, tabbypurr wrote:
On Tuesday, 16 June 2020 19:55:22 UTC+1, Dave Liquorice wrote:
On Tue, 16 Jun 2020 09:53:42 -0700 (PDT), tabbypurr wrote:

I suspect fanned rads will make a comeback some day once people
realise
they can have a much smaller rad without all the fan noise of the old
ones.

s/fanned/finned/ ?

Not sure what that means, but they do tend to go together. A fan
with a flat
panel works for a diy job but is not optimal design costwise for a new
product.

All you need for a fanned rad to work, take up way less space and be
much
preferred is silence,

I can see how you get quiet for a reasonable amount

http://openecohomes.org/diy-fanned-radiator/

But silent?

and that's not a challenge.

For you, maybe :-)

If an engineer isn't able to design a silent fan they had better stay
out of that business.

Moving any volume of air around inherently creates noise. An engineer
would know this, otherwise they best stay out of that business.

In principle, the convection you're relying on now to distribute
the heat from the radiator, that's moving air, and it's pretty
quiet. Suggesting human hearing is not infinitely sensitive.

Of course. And any suitable engineer knows that fan noise output depends on speed among other things. It is odd that some 'engineers' do not realise that fans can be slowed enough to be inaudible.


If you make the radiator large enough, you should be able to
match the fan-driven performance. With a large enough radiator,
the exhaust water temp will be the same as the room air temp.
That should be the limit.

Paul

FWIW you could do a slight bit better by wetting the metalwork at the outflow end. Evaporation could cool the outlet to slightly below ambient. Fairly pointless though.


NT

On 22/06/2020 17:29:59, wrote:
On Thursday, 18 June 2020 21:32:00 UTC+1, Fredxx wrote:
On 17/06/2020 12:48:21, tabbypurr wrote:
On Wednesday, 17 June 2020 04:45:08 UTC+1, RJH wrote:
On 16 Jun 2020 at 22:10:25 BST, tabbypurr wrote:
On Tuesday, 16 June 2020 19:55:22 UTC+1, Dave Liquorice wrote:
On Tue, 16 Jun 2020 09:53:42 -0700 (PDT), tabbypurr wrote:

I suspect fanned rads will make a comeback some day once people realise
they can have a much smaller rad without all the fan noise of the old
ones.

s/fanned/finned/ ?

Not sure what that means, but they do tend to go together. A fan with a flat
panel works for a diy job but is not optimal design costwise for a new
product.

All you need for a fanned rad to work, take up way less space and be much
preferred is silence,

I can see how you get quiet for a reasonable amount

http://openecohomes.org/diy-fanned-radiator/

But silent?

and that's not a challenge.

For you, maybe :-)

If an engineer isn't able to design a silent fan they had better stay out of that business.

Moving any volume of air around inherently creates noise. An engineer
would know this, otherwise they best stay out of that business.

I take it you're not an engineer then. Or an ignorant one.

Hint: try turning a desktop fan round by finger & see how noisy it is. No wind noise.

And precious little movement of air. It won't be very efficient!

On Monday, 22 June 2020 23:41:09 UTC+1, Fredxx wrote:
On 22/06/2020 17:29:59, tabbypurr wrote:
On Thursday, 18 June 2020 21:32:00 UTC+1, Fredxx wrote:
On 17/06/2020 12:48:21, tabbypurr wrote:
On Wednesday, 17 June 2020 04:45:08 UTC+1, RJH wrote:
On 16 Jun 2020 at 22:10:25 BST, tabbypurr wrote:
On Tuesday, 16 June 2020 19:55:22 UTC+1, Dave Liquorice wrote:
On Tue, 16 Jun 2020 09:53:42 -0700 (PDT), tabbypurr wrote:

I suspect fanned rads will make a comeback some day once people realise
they can have a much smaller rad without all the fan noise of the old
ones.

s/fanned/finned/ ?

Not sure what that means, but they do tend to go together. A fan with a flat
panel works for a diy job but is not optimal design costwise for a new
product.

All you need for a fanned rad to work, take up way less space and be much
preferred is silence,

I can see how you get quiet for a reasonable amount

http://openecohomes.org/diy-fanned-radiator/

But silent?

and that's not a challenge.

For you, maybe :-)

If an engineer isn't able to design a silent fan they had better stay out of that business.

Moving any volume of air around inherently creates noise. An engineer
would know this, otherwise they best stay out of that business.

I take it you're not an engineer then. Or an ignorant one.

Hint: try turning a desktop fan round by finger & see how noisy it is. No wind noise.

And precious little movement of air. It won't be very efficient!

Oh boy.
Time to state the utterly obvious...
1. The fan turned by finger demonstrates that fans can be silent.
2. Yes you will need more speed to make it useful.
3. There are suitable fan designs and suitable motors that run at suitable speeds to get a useful silent end result.
Clear enough for you yet?

In article ,
wrote:
Feel free to tell us where the inefficiency is in an oil filled
radiator. (I think we can assume it doesn't get so hot as to glow.)

Have it your own way. Some things are exactly 100% efficient. I take it
you work in advertising?

So you've no idea where any inefficiency occurs in that radiator, but
still want to make silly comments. Mmkay.

You've already been told why it isn't 100% efficient but choose to ignore
it.

--
*When chemists die, they barium.*

Dave Plowman London SW
To e-mail, change noise into sound.

In article ,
wrote:
Moving any volume of air around inherently creates noise. An engineer
would know this, otherwise they best stay out of that business.

I take it you're not an engineer then. Or an ignorant one.

Hint: try turning a desktop fan round by finger & see how noisy it is.
No wind noise.

Now try measuring with a sensitive device. Not your ancient ears. ;-)

--
*The only difference between a rut and a grave is the depth.

Dave Plowman London SW
To e-mail, change noise into sound.

On Tuesday, 23 June 2020 11:35:50 UTC+1, Dave Plowman (News) wrote:
In article ,
tabbypurr wrote:

Moving any volume of air around inherently creates noise. An engineer
would know this, otherwise they best stay out of that business.

I take it you're not an engineer then. Or an ignorant one.

Hint: try turning a desktop fan round by finger & see how noisy it is.
No wind noise.

Now try measuring with a sensitive device. Not your ancient ears. ;-)

another fact-free reply

On Tuesday, 23 June 2020 11:35:50 UTC+1, Dave Plowman (News) wrote:
In article ,
tabbypurr wrote:

Feel free to tell us where the inefficiency is in an oil filled
radiator. (I think we can assume it doesn't get so hot as to glow.)

Have it your own way. Some things are exactly 100% efficient. I take it
you work in advertising?

So you've no idea where any inefficiency occurs in that radiator, but
still want to make silly comments. Mmkay.

You've already been told why it isn't 100% efficient but choose to ignore
it.

No you've not come up with any inefficiency in such a rad. That's cos there isn't one.

In article ,
wrote:
Of course. And any suitable engineer knows that fan noise output depends on speed among other things. It is odd that some 'engineers' do not realise that fans can be slowed enough to be inaudible.


Really?

I worked in broadcasting. All studios are air sealed against noise. So if
in use for more than a short time, require ventilation. And despite this
being an extremely expensive part of the structure, and done by experts in
that field, none is totally silent.

But I'd guess in your world, the laws of physics don't apply. Hence you
talking about 100% efficiency too.

--
*The sooner you fall behind, the more time you'll have to catch up *

Dave Plowman London SW
To e-mail, change noise into sound.

On 22 Jun 2020 at 17:29:59 BST, "
wrote:

On Thursday, 18 June 2020 21:32:00 UTC+1, Fredxx wrote:
On 17/06/2020 12:48:21, tabbypurr wrote:
On Wednesday, 17 June 2020 04:45:08 UTC+1, RJH wrote:
snip

On Tuesday, 16 June 2020 19:55:22 UTC+1, Dave Liquorice wrote:
On Tue, 16 Jun 2020 09:53:42 -0700 (PDT), tabbypurr wrote:

I suspect fanned rads will make a comeback some day once people realise
they can have a much smaller rad without all the fan noise of the old
ones.

s/fanned/finned/ ?

Not sure what that means, but they do tend to go together. A fan with a flat
panel works for a diy job but is not optimal design costwise for a new
product.

All you need for a fanned rad to work, take up way less space and be much
preferred is silence,

I can see how you get quiet for a reasonable amount

http://openecohomes.org/diy-fanned-radiator/

But silent?

and that's not a challenge.

For you, maybe :-)

If an engineer isn't able to design a silent fan they had better stay out
of that business.

Moving any volume of air around inherently creates noise. An engineer
would know this, otherwise they best stay out of that business.

I take it you're not an engineer then. Or an ignorant one.

Hint: try turning a desktop fan round by finger & see how noisy it is. No
wind noise.


Oh well yes, even I could do that. Doesn't make me (or you) an engineer. Or
the room meaningfully warmer.

--
Cheers, Rob

In article ,
wrote:
On Tuesday, 23 June 2020 11:35:50 UTC+1, Dave Plowman (News) wrote:
In article ,
tabbypurr wrote:

Feel free to tell us where the inefficiency is in an oil filled
radiator. (I think we can assume it doesn't get so hot as to
glow.)

Have it your own way. Some things are exactly 100% efficient. I
take it you work in advertising?

So you've no idea where any inefficiency occurs in that radiator,
but still want to make silly comments. Mmkay.

You've already been told why it isn't 100% efficient but choose to
ignore it.

No you've not come up with any inefficiency in such a rad. That's cos
there isn't one.

You are showing yourself to be a fool.

The oil in that rad will circulate. And expand. Where to you think the
energy needed for that comes from?

If you'd said near 100% efficient, no argument.

--
*Learn from your parents' mistakes - use birth control

Dave Plowman London SW
To e-mail, change noise into sound.

On Tuesday, 23 June 2020 13:36:38 UTC+1, Dave Plowman (News) wrote:
In article ,
tabbypurr wrote:

Of course. And any suitable engineer knows that fan noise output depends on speed among other things. It is odd that some 'engineers' do not realise that fans can be slowed enough to be inaudible.


Really?

I worked in broadcasting. All studios are air sealed against noise. So if
in use for more than a short time, require ventilation. And despite this
being an extremely expensive part of the structure, and done by experts in
that field, none is totally silent.

With respect it's not difficult to make silent fans. Obviously they don't move a lot of air per size, so a given flow requires large blades & if ducted, large ducts. That you've seen cheaper noisy ones tells us precisely nothing.


But I'd guess in your world, the laws of physics don't apply. Hence you
talking about 100% efficiency too.

I don't understand why some people are just stuck on stupid.

On Tuesday, 23 June 2020 14:24:11 UTC+1, RJH wrote:
On 22 Jun 2020 at 17:29:59 BST, "tabbypurr wrote:

If an engineer isn't able to design a silent fan they had better stay out
of that business.

Moving any volume of air around inherently creates noise. An engineer
would know this, otherwise they best stay out of that business.

I take it you're not an engineer then. Or an ignorant one.

Hint: try turning a desktop fan round by finger & see how noisy it is. No
wind noise.


Oh well yes, even I could do that. Doesn't make me (or you) an engineer. Or
the room meaningfully warmer.

It makes the point that fans can be silent. Sorry, I thought that was utterly & completely obvious.


NT

On Tuesday, 23 June 2020 14:29:43 UTC+1, Dave Plowman (News) wrote:
In article ,
tabbypurr wrote:
On Tuesday, 23 June 2020 11:35:50 UTC+1, Dave Plowman (News) wrote:
In article ,
tabbypurr wrote:

Feel free to tell us where the inefficiency is in an oil filled
radiator. (I think we can assume it doesn't get so hot as to
glow.)

Have it your own way. Some things are exactly 100% efficient. I
take it you work in advertising?

So you've no idea where any inefficiency occurs in that radiator,
but still want to make silly comments. Mmkay.

You've already been told why it isn't 100% efficient but choose to
ignore it.

No you've not come up with any inefficiency in such a rad. That's cos
there isn't one.

You are showing yourself to be a fool.

The oil in that rad will circulate. And expand. Where to you think the
energy needed for that comes from?

Heat. And as the rad cools, as it does at some point, you find that every single bit of electricity consumed has turned to heat.

If you'd said near 100% efficient, no argument.

If you said you were 100% stupid there's be no argument.

Come on, yet again, I invite you to tell us what else the lost energy turns into apart from heat. See if you can think of something.

wrote:

On Tuesday, 23 June 2020 14:29:43 UTC+1, Dave Plowman (News) wrote:
In article ,
tabbypurr wrote:
On Tuesday, 23 June 2020 11:35:50 UTC+1, Dave Plowman (News) wrote:
In article ,
tabbypurr wrote:

Feel free to tell us where the inefficiency is in an oil filled
radiator. (I think we can assume it doesn't get so hot as to
glow.)

Have it your own way. Some things are exactly 100% efficient. I
take it you work in advertising?

So you've no idea where any inefficiency occurs in that radiator,
but still want to make silly comments. Mmkay.

You've already been told why it isn't 100% efficient but choose to
ignore it.

No you've not come up with any inefficiency in such a rad. That's cos
there isn't one.

You are showing yourself to be a fool.

The oil in that rad will circulate. And expand. Where to you think the
energy needed for that comes from?

Heat. And as the rad cools, as it does at some point, you find that every
single bit of electricity consumed has turned to heat.

If you'd said near 100% efficient, no argument.

If you said you were 100% stupid there's be no argument.

Come on, yet again, I invite you to tell us what else the lost energy
turns into apart from heat. See if you can think of something.

Yes. Thermodynamic issues which generally prevent even theoretical
100% efficiency of energy conversion actually work in your favour if you
are trying to convert other forms of energy to heat - or even just
transfer heat from a hot place to a cooler place; you are simply doing
your bit towards converting the universe to a homogenous slightly warm
thing.



--

Roger Hayter

On 23/06/2020 20:41, wrote:
On Tuesday, 23 June 2020 14:24:11 UTC+1, RJH wrote:
On 22 Jun 2020 at 17:29:59 BST, "tabbypurr wrote:

If an engineer isn't able to design a silent fan they had better stay out
of that business.

Moving any volume of air around inherently creates noise. An engineer
would know this, otherwise they best stay out of that business.

I take it you're not an engineer then. Or an ignorant one.

Hint: try turning a desktop fan round by finger & see how noisy it is. No
wind noise.


Oh well yes, even I could do that. Doesn't make me (or you) an engineer. Or
the room meaningfully warmer.

It makes the point that fans can be silent.

Perhaps very quite and mostly useless would be closer to the truth.

Yes big slower fans are quieter than smaller faster ones for the same
air flow, but none are silent. If you are shifting a volume of air, you
will get noise from that even without the fan... Ever heard the wind blow?

Sorry, I thought that was utterly & completely obvious.

Yeah Nige, you would.



--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

"John Rumm" wrote in message
o.uk...
On 23/06/2020 20:41, wrote:
On Tuesday, 23 June 2020 14:24:11 UTC+1, RJH wrote:
On 22 Jun 2020 at 17:29:59 BST, "tabbypurr wrote:

If an engineer isn't able to design a silent fan they had better stay
out
of that business.

Moving any volume of air around inherently creates noise. An engineer
would know this, otherwise they best stay out of that business.

I take it you're not an engineer then. Or an ignorant one.

Hint: try turning a desktop fan round by finger & see how noisy it is.
No
wind noise.


Oh well yes, even I could do that. Doesn't make me (or you) an engineer.
Or
the room meaningfully warmer.

It makes the point that fans can be silent.

Perhaps very quite and mostly useless would be closer to the truth.

Nope, the fan in my heatbank is completely silent and nothing like useless.

Yes big slower fans are quieter than smaller faster ones for the same air
flow, but none are silent.

Mine is.

If you are shifting a volume of air, you will get noise from that even
without the fan...

Thats bull**** too with the volume of air from a radiator.

Ever heard the wind blow?

Thats the trees and houses and you cant hear the air in a
light breeze without any trees or bushed or buildings.

On Wed, 24 Jun 2020 14:05:13 +1000, cantankerous trolling geezer Rodent
Speed, the auto-contradicting senile sociopath, blabbered, again:

FLUSH the obnoxious senile asshole's latest troll**** unread

--
The Natural Philosopher about senile Rodent:
"Rod speed is not a Brexiteer. He is an Australian troll and arsehole."
Message-ID:

In article ,
wrote:
I worked in broadcasting. All studios are air sealed against noise. So
if in use for more than a short time, require ventilation. And despite
this being an extremely expensive part of the structure, and done by
experts in that field, none is totally silent.

With respect it's not difficult to make silent fans. Obviously they
don't move a lot of air per size, so a given flow requires large blades
& if ducted, large ducts. That you've seen cheaper noisy ones tells us
precisely nothing.

With 'respect' if you think broadcast companies etc go for cheap noisy
ventilation fans in a proper studio installation, you are even more stupid
than you first appear.


But I'd guess in your world, the laws of physics don't apply. Hence you
talking about 100% efficiency too.

I don't understand why some people are just stuck on stupid.

You don't understand yourself then? Only a fool talks about 100%
efficiency with anything.

--
*Always borrow money from pessimists - they don't expect it back *

Dave Plowman London SW
To e-mail, change noise into sound.

On 24/06/2020 05:05:13, Rod Speed wrote:


"John Rumm" wrote in message
o.uk...
On 23/06/2020 20:41, wrote:
On Tuesday, 23 June 2020 14:24:11 UTC+1, RJHÂ* wrote:
On 22 Jun 2020 at 17:29:59 BST, "tabbypurr wrote:

If an engineer isn't able to design a silent fan they had better
stay out
of that business.

Moving any volume of air around inherently creates noise. An engineer
would know this, otherwise they best stay out of that business.

I take it you're not an engineer then. Or an ignorant one.

Hint: try turning a desktop fan round by finger & see how noisy it
is. No
wind noise.


Oh well yes, even I could do that. Doesn't make me (or you) an
engineer. Or
the room meaningfully warmer.

It makes the point that fans can be silent.

Perhaps very quite and mostly useless would be closer to the truth.

Nope, the fan in my heatbank is completely silent and nothing like useless.

Yes big slower fans are quieter than smaller faster ones for the same
air flow, but none are silent.

Mine is.

That's because you're deaf.

If you are shifting a volume of air, you will get noise from that even
without the fan...

Thats bull**** too with the volume of air from a radiator.

That is because it is not mechanically 'moved'. This thread was making
more efficient radiators from some addition help to move the air. Do
keep up.

Ever heard the wind blow?

Thats the trees and houses and you cant hear the air in a
light breeze without any trees or bushed or buildings.

Moving air is going to impinge on something solid; eventually.

On Wednesday, 24 June 2020 01:25:52 UTC+1, John Rumm wrote:
On 23/06/2020 20:41, tabbypurr wrote:
On Tuesday, 23 June 2020 14:24:11 UTC+1, RJH wrote:
On 22 Jun 2020 at 17:29:59 BST, "tabbypurr wrote:

If an engineer isn't able to design a silent fan they had better stay out
of that business.

Moving any volume of air around inherently creates noise. An engineer
would know this, otherwise they best stay out of that business.

I take it you're not an engineer then. Or an ignorant one.

Hint: try turning a desktop fan round by finger & see how noisy it is. No
wind noise.


Oh well yes, even I could do that. Doesn't make me (or you) an engineer. Or
the room meaningfully warmer.

It makes the point that fans can be silent.

Perhaps very quite and mostly useless would be closer to the truth.

wrong again

Yes big slower fans are quieter than smaller faster ones for the same
air flow, but none are silent.

wrong again

If you are shifting a volume of air, you
will get noise from that even without the fan... Ever heard the wind blow?

noise ceases to occur when airspeed is low. And obviously most fans are not noise optimised. Even my first 1k rpm fan was completely silent.


Sorry, I thought that was utterly & completely obvious.

Yeah Nige, you would.

If someone can't follow an elementary point... shrug.

Why do you keep calling me Nige?


NT

On Wednesday, 24 June 2020 11:36:55 UTC+1, Dave Plowman (News) wrote:
In article ,
tabbypurr wrote:

I worked in broadcasting. All studios are air sealed against noise. So
if in use for more than a short time, require ventilation. And despite
this being an extremely expensive part of the structure, and done by
experts in that field, none is totally silent.

With respect it's not difficult to make silent fans. Obviously they
don't move a lot of air per size, so a given flow requires large blades
& if ducted, large ducts. That you've seen cheaper noisy ones tells us
precisely nothing.

With 'respect' if you think broadcast companies etc go for cheap noisy
ventilation fans in a proper studio installation, you are even more stupid
than you first appear.

In my experience of only 2, and observations of a few others, broadcast companies typically know very little about science or physics, and when other companies offer them products lavishly praised they pick from those. They make routinely not the best choices. Fan companies, like any other copmany, of course are not normally building for top quality, when they say they are they normally build for relatively good quality with various cost cutting measures. Add on a nice markup, praise it to the skies and there you have a commercial product. The same pattern occurs in business sector after business sector.


But I'd guess in your world, the laws of physics don't apply. Hence you
talking about 100% efficiency too.

I don't understand why some people are just stuck on stupid.

You don't understand yourself then? Only a fool talks about 100%
efficiency with anything.

I've invited you again and again to tell us what else the radiator produces than heat. You failed. And no, it still doesn't get hot enough to glow.

'Nothing is 100% efficient' is a good rule of thumb. Like any idiot you confuse oversimplified rules of thumb with actual reality.


NT

On Wednesday, 24 June 2020 12:52:39 UTC+1, Fredxx wrote:
On 24/06/2020 05:05:13, Rod Speed wrote:
"John Rumm" wrote in message
o.uk...
On 23/06/2020 20:41, tabbypurr wrote:
On Tuesday, 23 June 2020 14:24:11 UTC+1, RJHÂ* wrote:
On 22 Jun 2020 at 17:29:59 BST, "tabbypurr wrote:

If an engineer isn't able to design a silent fan they had better
stay out
of that business.

Moving any volume of air around inherently creates noise. An engineer
would know this, otherwise they best stay out of that business.

I take it you're not an engineer then. Or an ignorant one.

Hint: try turning a desktop fan round by finger & see how noisy it
is. No
wind noise.


Oh well yes, even I could do that. Doesn't make me (or you) an
engineer. Or
the room meaningfully warmer.

It makes the point that fans can be silent.

Perhaps very quite and mostly useless would be closer to the truth.

Nope, the fan in my heatbank is completely silent and nothing like useless.

Yes big slower fans are quieter than smaller faster ones for the same
air flow, but none are silent.

Mine is.

That's because you're deaf.

If you are shifting a volume of air, you will get noise from that even
without the fan...

Thats bull**** too with the volume of air from a radiator.

That is because it is not mechanically 'moved'. This thread was making
more efficient radiators from some addition help to move the air. Do
keep up.

Ever heard the wind blow?

Thats the trees and houses and you cant hear the air in a
light breeze without any trees or bushed or buildings.

Moving air is going to impinge on something solid; eventually.

Obviously there are plenty of daily scenarios in which air moves but people don't hear it.


NT

On 24/06/2020 22:45, wrote:
On Wednesday, 24 June 2020 01:25:52 UTC+1, John Rumm wrote:
On 23/06/2020 20:41, tabbypurr wrote:
On Tuesday, 23 June 2020 14:24:11 UTC+1, RJH wrote:
On 22 Jun 2020 at 17:29:59 BST, "tabbypurr wrote:

If an engineer isn't able to design a silent fan they had better stay out
of that business.

Moving any volume of air around inherently creates noise. An engineer
would know this, otherwise they best stay out of that business.

I take it you're not an engineer then. Or an ignorant one.

Hint: try turning a desktop fan round by finger & see how noisy it is. No
wind noise.


Oh well yes, even I could do that. Doesn't make me (or you) an engineer. Or
the room meaningfully warmer.

It makes the point that fans can be silent.

Perhaps very quite and mostly useless would be closer to the truth.

wrong again

Yes big slower fans are quieter than smaller faster ones for the same
air flow, but none are silent.

wrong again

If you are shifting a volume of air, you
will get noise from that even without the fan... Ever heard the wind blow?

noise ceases to occur when airspeed is low. And obviously most fans are not noise optimised. Even my first 1k rpm fan was completely silent.



You keep using "silent" without defining what you mean. So I suspect
you are through the looking glass and playing Humpty Dumpty. Meanwhile
the rest of us in the world where "completely silent" requires the
absence of any acoustic waves - whether or not you can hear them with
your particular ears at whatever distance you are listening. Good luck
achieving that with a fan. And even if you define "silent" by reference
to your ear at your distance, don't attach "completely" until you've
checked what happens if you run 1,000 of the fans in the room at the
same time.

--
Robin
reply-to address is (intended to be) valid

In article ,
wrote:
With 'respect' if you think broadcast companies etc go for cheap noisy
ventilation fans in a proper studio installation, you are even more
stupid than you first appear.

In my experience of only 2, and observations of a few others, broadcast
companies typically know very little about science or physics, and when
other companies offer them products lavishly praised they pick from
those. They make routinely not the best choices. Fan companies, like any
other copmany, of course are not normally building for top quality, when
they say they are they normally build for relatively good quality with
various cost cutting measures. Add on a nice markup, praise it to the
skies and there you have a commercial product. The same pattern occurs
in business sector after business sector.

There you have it then. A great business opportunity for you. Make silent
ventilation systems for studios. And indeed everywhere - as I doubt many
like the noise of air moving, or the bits needed to do this.

BTW, if you think broadcast companies know little about science or
physics. you could do some simple research on just how many such things
were invented and developed by the likes of the BBC and ITV. As well as
the parent companies of recording studios. But that would show just how
little you know about such things.






But I'd guess in your world, the laws of physics don't apply.
Hence you talking about 100% efficiency too.

I don't understand why some people are just stuck on stupid.

You don't understand yourself then? Only a fool talks about 100%
efficiency with anything.

I've invited you again and again to tell us what else the radiator
produces than heat. You failed. And no, it still doesn't get hot enough
to glow.

Are you really as thick as you appear? As a radiator heats, it expands.
Where do you thing the energy needed for that comes from? Etc etc.

'Nothing is 100% efficient' is a good rule of thumb. Like any idiot you
confuse oversimplified rules of thumb with actual reality.

How long are you going to continue digging this hole for yourself?

--
*When the chips are down, the buffalo is empty*

Dave Plowman London SW
To e-mail, change noise into sound.

In article ,
wrote:
Moving air is going to impinge on something solid; eventually.

Obviously there are plenty of daily scenarios in which air moves but
people don't hear it.

Would that depend on your hearing? Or do you work to an average with
everything? Like 100% ;-)

--
*OK, so what's the speed of dark? *

Dave Plowman London SW
To e-mail, change noise into sound.