Miks15
|
| posted on 6/1/09 at 09:42 PM |
|
|
radiator angle
Whats the max angle you can tilt the rad at?
Ive found a good place for it to sit but it has to sit at about 45 degrees. Is this to much? Im planning an enclosure around it to duct the air
through it, will it be enough?
Thanks
Mikkel
|
|
|
|
|
blakep82
|
| posted on 6/1/09 at 09:50 PM |
|
|
a very good question... don't know the answer, but i'd be interested.
I probably wouldn't want to go much more that 45 degrees. i guess at 45 degrees, you're effectively halfing its surface area (if that
makes sense)
and air may tend to flow over the top of it, rather than through it. but if you're ducting it it shold help.
are you using the BMW radiator?
[Edited on 6/1/09 by blakep82]
________________________
IVA manual link http://www.businesslink.gov.uk/bdotg/action/detail?type=RESOURCES&itemId=1081997083
don't write OT on a new thread title, you're creating the topic, everything you write is very much ON topic!
|
|
|
tomgregory2000
|
| posted on 6/1/09 at 10:02 PM |
|
|
i believe that a rad should be angled buy a small amount as the air is forced onto the cooling fins, not just straight past.
but i could be completly wrong and it could be something i have made up in my head
|
|
|
Dangle_kt
|
| posted on 6/1/09 at 10:04 PM |
|
|
Look at the rad fins, you will get the most efficiency from keeping the angle of the air flow (and rad) 90 degrees to the angle of the fins - which is
usually vertical. If the angle is too great then no air will flow through it, so you may have issues in traffic or have to run the fan constantly to
keep air moving through it.
Mine has a slight angle, but not enough to stop air flow.
|
|
|
Dangle_kt
|
| posted on 6/1/09 at 10:05 PM |
|
|
Look at the rad fins, you will get the most efficiency from keeping the angle of the air flow (and rad) 90 degrees to the angle of the fins - which is
usually vertical. If the angle is too great then no air will flow through it, so you may have issues in traffic or have to run the fan constantly to
keep air moving through it.
Mine has a slight angle, but not enough to stop air flow.
|
|
|
BenB
|
| posted on 6/1/09 at 10:08 PM |
|
|
I heard 10 degrees backwards as optimum though it might be urban myth....
|
|
|
MikeRJ
|
| posted on 6/1/09 at 10:14 PM |
|
|
quote:
Originally posted by blakep82
I probably wouldn't want to go much more that 45 degrees. i guess at 45 degrees, you're effectively halfing its surface area (if that
makes sense)
Tut, tut, someone didn't pay attention in geometry  The effective height will be 0.707 at 45 degrees and 0.5 at 60 degrees (from
vertical).
I suspect effective area probably drops off more quickly than that suggests though, since the air can't flow straight through the core when
it's tilted.
[Edited on 6/1/09 by MikeRJ]
|
|
|
blakep82
|
| posted on 6/1/09 at 10:20 PM |
|
|
quote:
Originally posted by MikeRJ
quote:
Originally posted by blakep82
I probably wouldn't want to go much more that 45 degrees. i guess at 45 degrees, you're effectively halfing its surface area (if that
makes sense)
Tut, tut, someone didn't pay attention in geometry The effective height will be 0.707 at 45 degrees and 0.5 at 60 degrees (from
vertical).
I suspect effective area probably drops off more quickly than that suggests though, since the air can't flow straight through the core when
it's tilted.
[Edited on 6/1/09 by MikeRJ]
damn right i didn't pay attention
funny story though, scottish highers work different from english A levels, instead of a 2year course and 1 exam (like a levels), here its 1 year and
then a final exam in 5th year, then you can do it again in 6th year if you fail, or do others if you pass. each year, 1 exam paper in the morning, and
a 2nd one in the afternoon.
i failed maths miserably in 5th year, no worries, i'll do it again in 6th year. look up the scottish highers nonsense in 2000. we were all given
a exam paper with questions on subjects we hadn't been taught. as a result, most of scotland didn't bother going back for the 2nd one in
the afternoon, i did, and wrote a few things on the paper, didn't actually answer a full question i think.
as a result, the pass mark was dropped, and i barely scraped a C pass only got about 40% or something lol
it was a pass, good enough for me!
________________________
IVA manual link http://www.businesslink.gov.uk/bdotg/action/detail?type=RESOURCES&itemId=1081997083
don't write OT on a new thread title, you're creating the topic, everything you write is very much ON topic!
|
|
|
rachaeljf
|
| posted on 6/1/09 at 10:21 PM |
|
|
As long as you have a suitable cowling or ducting to the rad it doesn't matter what angle it is set at. You can have the rad end on to the
general direction of travel if you get your ducting right!
The important thing is to provide sufficient frontal area for your duct/cowl, say around 1000 sq mm (about a foot square) for up to 120 bhp. Make sure
the cowl extends out in front of the rad so it will "trap" the incoming air and form a high pressure area in front of the rad. Then make
sure the air you "trap" all goes through the rad and cannot spill around the sides. Also make sure there is at least as much cross section
area behind the rad for the heated air to escape. This also means your fan must not block the airway too much.
Hope that helps. Cheers R
|
|
|
Liam
|
| posted on 7/1/09 at 12:07 AM |
|
|
As above. I've seen completely horizontal radiators (or heat exchangers for various purposes, generally). No problem if the air is flowing
through them in the right direction.
Liam
[Edited on 7/1/09 by Liam]
|
|
|
DIY Si
|
| posted on 7/1/09 at 01:05 AM |
|
|
The Elise has a near horizontal rad, and they seem to do alright. As said though, you may need to run the fan more often, but once moving any ducting
will sort that out.
“Let your plans be dark and as impenetratable as night, and when you move, fall like a thunderbolt.”
Sun Tzu, The Art of War
My new blog: http://spritecave.blogspot.co.uk/
|
|
|
Avoneer
|
| posted on 7/1/09 at 07:58 AM |
|
|
If it's leaning forward and enclosed in ducting, don't you have the danger of creating lift?
Pat...
No trees were killed in the sending of this message.
However a large number of electrons were terribly inconvenienced.
|
|
|
JAG
|
| posted on 7/1/09 at 08:19 AM |
|
|
If the radiator leans forward (top further forward than the bottom) you will create lift but it should be quite small. You can also create downforce
of a similar magnitude by leaning the radiator backwords - both systems will need suitable ducting.
It will depend upon the pressure drop across the radiator, usually very small, and the area of the radiator.
[Edited on 7/1/09 by JAG]
Justin
Who is this super hero? Sarge? ...No.
Rosemary, the telephone operator? ...No.
Penry, the mild-mannered janitor? ...Could be!
|
|
|
Miks15
|
| posted on 7/1/09 at 09:07 AM |
|
|
thank you all for your comments, i think im going to try laving it as it is at the minute and then making a ducting and posting pisture to get your
comments then.
Also i am using a polo rad not the BMW rad(was too wide)
|
|
|
Mr Whippy
|
| posted on 7/1/09 at 09:13 AM |
|
|
these cars must be very very light if the lift generated by a radiator is being discussed 
Fame is when your old car is plastered all over the internet
|
|
|
nick205
|
| posted on 7/1/09 at 09:24 AM |
|
|
quote:
Originally posted by Mr Whippy
these cars must be very very light if the lift generated by a radiator is being discussed
BMW motor so can't be that light 
You're not letting your mind wander off the down the BEC path again are you Whip?
|
|
|
Mr Whippy
|
| posted on 7/1/09 at 10:09 AM |
|
|
quote:
Originally posted by nick205
quote:
Originally posted by Mr Whippy
these cars must be very very light if the lift generated by a radiator is being discussed
You're not letting your mind wander off the down the BEC path again are you Whip?
Sorry haven't seen any flying pigs recently...
Fame is when your old car is plastered all over the internet
|
|
|
02GF74
|
| posted on 7/1/09 at 12:10 PM |
|
|
I am no expert here but I would say the important thing is the angle of the radiator fins to the direction of air flow.
As mentioned, you can mount a radiator horizontally but that is f.a. use if the air flow is horizontal too!!! (top diagram) - in these instances
there has to be cowling to direct the air so it is perpendicular to the radiator. (lower diagram)
Now the question as I understand it is or maybe sold be, what angle can the radiator fins be to the air flow?
Obvisously the larger this is, the harder it is for air to flow through the radiator.
Unfortunately I do not know the answer and it may also depends on the speed of the air too as any object with mass does not like to change
direction.
A lot of motorcycles have radiators off-vertical but I think that angle is quite small, less than 30 degrees I'd say.
 
Rescued attachment rad flow.JPG
|
|
|
DavidM
|
| posted on 7/1/09 at 01:24 PM |
|
|
According to an article in PPC about a year ago the optimum angle is 20 degrees from perpedicular. So on a Locost the top would lean back 20
degrees.
It was something to do with being more efficient if the airflow is interrupted.
Proportion is Everything
|
|
|
02GF74
|
| posted on 7/1/09 at 02:12 PM |
|
|
20 degrees?
interesting. are you able to scan the article? or at least say haow they worked this out?
I have never seen a car radiator fitted at anything other than vertical - one would have though that if mounting it at an angle made it more
efficient, this would mean a smaller = cheaper radiator would be used by car manufacturers.
|
|
|
bimbleuk
|
| posted on 7/1/09 at 03:51 PM |
|
|
quote:
Originally posted by 02GF74
I have never seen a car radiator fitted at anything other than vertical
As above go look at an Elise the radiator its basically horizontal. Duct collects air at the front and exhausts out the top of the front cover. Only
issue is that new owners think they have a radiator leak when they get clouds of steam in the morning as any condensation/rain vaporises from the top
of the radiator!
As a guide you only actually need about 1/4 of the frontal area of the radiator to feed sufficient air and so long as theres a pressure drop across
the radiator then the air should flow freely. So ducting air away from the back of the radiator is just as important!
|
|
|
nick205
|
| posted on 7/1/09 at 03:52 PM |
|
|
quote:
Originally posted by 02GF74
20 degrees?
interesting. are you able to scan the article? or at least say haow they worked this out?
I have never seen a car radiator fitted at anything other than vertical - one would have though that if mounting it at an angle made it more
efficient, this would mean a smaller = cheaper radiator would be used by car manufacturers.
For OEMs it may be more down to packaging, assembly and common parts than outright efficiency of the rad itself.
|
|
|
02GF74
|
| posted on 7/1/09 at 04:11 PM |
|
|
quote:
Originally posted by bimbleuk
quote:
Originally posted by 02GF74
I have never seen a car radiator fitted at anything other than vertical
As above go look at an Elise the radiator its basically horizontal. Duct collects air at the front and exhausts out the top of the front cover. Only
issue is that new owners think they have a radiator leak when they get clouds of steam in the morning as any condensation/rain vaporises from the top
of the radiator!
As a guide you only actually need about 1/4 of the frontal area of the radiator to feed sufficient air and so long as theres a pressure drop across
the radiator then the air should flow freely. So ducting air away from the back of the radiator is just as important!
Wo't an elise then? I was referring to mass produced tin tops!
I find it hard to believe that if I cover up 3/4 of the radiator in my volvo I will not get problems  not going to try that even in this weather.
|
|
|
Liam
|
| posted on 7/1/09 at 05:25 PM |
|
|
Er he don't mean cover up 3/4 of the rad! Just that the size of the upstream opening doesn't have to be as big as the whole rad itself.
|
|
|
%20(WinCE).JPG)
