K
kony
Nope, we already know that lower airflow through a fan means
less turbulence out of the fan, and lower flow over a hot
surface means less turbulence ON that surface.
But, you'll never understand if you don't test, will you
Tim?
Test.
You are using an out of date browser. It may not display this or other websites correctly.
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You should upgrade or use an alternative browser.
Nope, we already know that lower airflow through a fan means
less turbulence out of the fan, and lower flow over a hot
surface means less turbulence ON that surface.
But, you'll never understand if you don't test, will you
Tim?
Test.
K
kony
Isn't it interesting, then, that when air intake through the fan was
restricted, the cooling increased.
Nope, it's interesting that you dismiss the abilities of the
author in a prior post then try to claim the assessment of
the change is somehow different, and then totally ignore the
invalidity of the "cooling increased" concept from single
point measurements, as well as ignoring that reducing fan
intake rate will reduce turbulence.
K
kony
In the absence of a
dedicated fan, those parts can benefit from increased cooling
by increased turbulence.
IF all else were equal, which is not the case. You can have
turbulence, at expense of airflow (which will raise temps
and even potentially, completely offset the turbulence on
the parts being cooled, be more turbulence on them from the
higher flow rate), or at expense of noise. If you don't
mind that noise, you could have had even more airflow unless
you have a very space constrained chassis such as some 1U
racks.
T
Timothy Daniels
T
Timothy Daniels
kornball said:BS again Tim.
http://www.thermaflo.com/crosscut.shtml
"Turbulent air breaks the stagnant air boundary layers
around the pins and, as a result, enhances the heat sink's
thermal performance."
http://www.frostytech.com/articleview.cfm?articleID=2001
"To induce turbulence within the fins and improve thermal
transmission between the air and metal, Thermalright have
modified the aluminum fins by adding 'proprietary bent winglets'."
http://sound.westhost.com/heatsinks.htm
"Simple convection is not as effective (even for the same rate
of flow of air), because of the "laminar" flow of air (where the
air at the surface of the heatsink moves slower than that further
away). This effect can be easily seen on a windy day. If you stay
close to a wall or other large area (lying on the ground works too),
it will be noticed that it is less windy than out in the open. Exactly
the same thing happens with heatsinks (but on a somewhat
reduced scale). Creating turbulence is an excellent way to defeat
this process, but this requires fans, and fans are noisy."
http://www.fischerelektronik.de/fischer2002/fischer/Fachb-Act_Rep/kuehlkonzepte/KKoneng_e.htm
"The heat transfer towards the flowing air that can be achieved
with plain fins is relatively restricted. The laminar air flow that
emerges is not sufficient to carry off the heat. Therefore, attempts
are being made to improve heat transfer (fins to air) by producing
more turbulent flow using an appropriate fin geometry."
http://www.hilltech.com/products/uv_components/UV_irradiators.html
"Optimizing cooling efficiency in an LIA is achieved by using
a heatsink-based aluminum reflector, where the material has
a high thermal conductivity and the design maximizes the effects
of surface area and turbulence. Within reason, the more surface
area the better the lamp cooling. Also important is turbulence,
because of the skin effect in cooling. A thin layer of air surrounding
a cooling surface acts as a thermal insulator impeding the effect
of forced air-cooling. This layer needs to be disrupted by turbulent
airflow, which can be created by providing irregular fins and fin
geometries."
http://www.freepatentsonline.com/6729383.html
"at least some said protrusions affect said streaming of said
fluid so as to enhance the turbulence of said streaming of said
fluid, thereby enhancing convective heat transfer from said
object to said fluid."
http://www.overclockers.com/tips90/ -
"Turbulent air cools better. Say, for sake of argument,
you have a simple tube with a fan in the middle. The fan pulls
air from one side of the tube, and blows into the other. If you
have a hot component on the exhaust side of the fan, it will
be more efficiently cooled than on the intake side.
"This is because the air on the exhaust side of the fan
is more turbulent. For lack of a better explanation, the loops
and whorls of turbulent air moving across the surface pick
up more heat. The effective surface area of the object is
increased. (Actually, it was explained to me by saying the
effective surface area of the air is increased.) The total
volume of airflow remains the same, but turbulent air just
cools better."
http://www.begellhouse.com/books/497d60632054f587,6ddfe1a32b58c789.html -
"Turbulent flow is the most common form of motion of liquids
and gases playing the role of the heat-transfer medium in thermal
systems. The complexity of turbulent flow and the importance of
hydrodynamics and heat transfer in practice inspired continuing
research for methods of efficient heat augmentation by the
Lithuanian Energy Institute. The solution of this problem was directly
linked with the determination of the reaction of flow in the boundary
layer to the effect of various factors and heat transfer rate under
given conditions. The investigated factors included elevated degree
of turbulence of the external flow as well as strong acceleration and
turbulization of flow near the wall by surface roughness. The material
in this volume shows that it is possible to control the efficiency of
turbulent transfer when the vortical structure of the turbulent flow is
known."
http://www.cougarlabs.com/cool2.html -
"For convective heat transfer to work well, we need to get the
heat energy out into the flowing coolant. Turbulence will do this
for us."
http://www.ceere.org/beep/docs/FY2002/Turbulent_Flow_in_Enclosure.pdf -
"Comparatively speaking, turbulent flows often lead to higher
transport rate of momentum, energy and mass than laminar flows.
These features are widely made use of in energy systems in industry.
For example, turbulence enhancers such as ribs are added to
cooling systems of turbine blades and microelectronic devices
to create more turbulent motions so that the overall heat transfer
efficiency can be improved."
*TimDaniels*
".
T
Timothy Daniels
"kornball" knows all:
Not when the air entering the fan must make a right angle turn,
AND when the increased air flow from the edges must ALSO
make a right angle turn. Right angle turns ALWAYS increase
turbulence. The result of both these occurrences had to have
been increased turbulence inside the case.
What is funny in all your rantings is that YOU have never
tested for turbulence versus laminar flow. You just
assumed sometime in the dim past that laminar flow
was best, and you've never tested that theory despite
all the information availabel to you that says the contrary:
http://www.thermaflo.com/crosscut.shtml
"Turbulent air breaks the stagnant air boundary layers
around the pins and, as a result, enhances the heat sink's
thermal performance."
http://www.frostytech.com/articleview.cfm?articleID=2001
"To induce turbulence within the fins and improve thermal
transmission between the air and metal, Thermalright have
modified the aluminum fins by adding 'proprietary bent winglets'."
http://sound.westhost.com/heatsinks.htm
"Simple convection is not as effective (even for the same rate
of flow of air), because of the "laminar" flow of air (where the
air at the surface of the heatsink moves slower than that further
away). This effect can be easily seen on a windy day. If you stay
close to a wall or other large area (lying on the ground works too),
it will be noticed that it is less windy than out in the open. Exactly
the same thing happens with heatsinks (but on a somewhat
reduced scale). Creating turbulence is an excellent way to defeat
this process, but this requires fans, and fans are noisy."
http://www.fischerelektronik.de/fischer2002/fischer/Fachb-Act_Rep/kuehlkonzepte/KKoneng_e.htm
"The heat transfer towards the flowing air that can be achieved
with plain fins is relatively restricted. The laminar air flow that
emerges is not sufficient to carry off the heat. Therefore, attempts
are being made to improve heat transfer (fins to air) by producing
more turbulent flow using an appropriate fin geometry."
http://www.hilltech.com/products/uv_components/UV_irradiators.html
"Optimizing cooling efficiency in an LIA is achieved by using
a heatsink-based aluminum reflector, where the material has
a high thermal conductivity and the design maximizes the effects
of surface area and turbulence. Within reason, the more surface
area the better the lamp cooling. Also important is turbulence,
because of the skin effect in cooling. A thin layer of air surrounding
a cooling surface acts as a thermal insulator impeding the effect
of forced air-cooling. This layer needs to be disrupted by turbulent
airflow, which can be created by providing irregular fins and fin
geometries."
http://www.freepatentsonline.com/6729383.html
"at least some said protrusions affect said streaming of said
fluid so as to enhance the turbulence of said streaming of said
fluid, thereby enhancing convective heat transfer from said
object to said fluid."
http://www.overclockers.com/tips90/ -
"Turbulent air cools better. Say, for sake of argument,
you have a simple tube with a fan in the middle. The fan pulls
air from one side of the tube, and blows into the other. If you
have a hot component on the exhaust side of the fan, it will
be more efficiently cooled than on the intake side.
"This is because the air on the exhaust side of the fan
is more turbulent. For lack of a better explanation, the loops
and whorls of turbulent air moving across the surface pick
up more heat. The effective surface area of the object is
increased. (Actually, it was explained to me by saying the
effective surface area of the air is increased.) The total
volume of airflow remains the same, but turbulent air just
cools better."
http://www.begellhouse.com/books/497d60632054f587,6ddfe1a32b58c789.html -
"Turbulent flow is the most common form of motion of liquids
and gases playing the role of the heat-transfer medium in thermal
systems. The complexity of turbulent flow and the importance of
hydrodynamics and heat transfer in practice inspired continuing
research for methods of efficient heat augmentation by the
Lithuanian Energy Institute. The solution of this problem was directly
linked with the determination of the reaction of flow in the boundary
layer to the effect of various factors and heat transfer rate under
given conditions. The investigated factors included elevated degree
of turbulence of the external flow as well as strong acceleration and
turbulization of flow near the wall by surface roughness. The material
in this volume shows that it is possible to control the efficiency of
turbulent transfer when the vortical structure of the turbulent flow is
known."
http://www.cougarlabs.com/cool2.html -
"For convective heat transfer to work well, we need to get the
heat energy out into the flowing coolant. Turbulence will do this
for us."
http://www.ceere.org/beep/docs/FY2002/Turbulent_Flow_in_Enclosure.pdf -
"Comparatively speaking, turbulent flows often lead to higher
transport rate of momentum, energy and mass than laminar flows.
These features are widely made use of in energy systems in industry.
For example, turbulence enhancers such as ribs are added to
cooling systems of turbine blades and microelectronic devices
to create more turbulent motions so that the overall heat transfer
efficiency can be improved."
*TimDaniels*
Nope, we already know that lower airflow through a fan means
less turbulence out of the fan, and lower flow over a hot
surface means less turbulence ON that surface.
Not when the air entering the fan must make a right angle turn,
AND when the increased air flow from the edges must ALSO
make a right angle turn. Right angle turns ALWAYS increase
turbulence. The result of both these occurrences had to have
been increased turbulence inside the case.
But, you'll never understand if you don't test, will you
Tim?
What is funny in all your rantings is that YOU have never
tested for turbulence versus laminar flow. You just
assumed sometime in the dim past that laminar flow
was best, and you've never tested that theory despite
all the information availabel to you that says the contrary:
http://www.thermaflo.com/crosscut.shtml
"Turbulent air breaks the stagnant air boundary layers
around the pins and, as a result, enhances the heat sink's
thermal performance."
http://www.frostytech.com/articleview.cfm?articleID=2001
"To induce turbulence within the fins and improve thermal
transmission between the air and metal, Thermalright have
modified the aluminum fins by adding 'proprietary bent winglets'."
http://sound.westhost.com/heatsinks.htm
"Simple convection is not as effective (even for the same rate
of flow of air), because of the "laminar" flow of air (where the
air at the surface of the heatsink moves slower than that further
away). This effect can be easily seen on a windy day. If you stay
close to a wall or other large area (lying on the ground works too),
it will be noticed that it is less windy than out in the open. Exactly
the same thing happens with heatsinks (but on a somewhat
reduced scale). Creating turbulence is an excellent way to defeat
this process, but this requires fans, and fans are noisy."
http://www.fischerelektronik.de/fischer2002/fischer/Fachb-Act_Rep/kuehlkonzepte/KKoneng_e.htm
"The heat transfer towards the flowing air that can be achieved
with plain fins is relatively restricted. The laminar air flow that
emerges is not sufficient to carry off the heat. Therefore, attempts
are being made to improve heat transfer (fins to air) by producing
more turbulent flow using an appropriate fin geometry."
http://www.hilltech.com/products/uv_components/UV_irradiators.html
"Optimizing cooling efficiency in an LIA is achieved by using
a heatsink-based aluminum reflector, where the material has
a high thermal conductivity and the design maximizes the effects
of surface area and turbulence. Within reason, the more surface
area the better the lamp cooling. Also important is turbulence,
because of the skin effect in cooling. A thin layer of air surrounding
a cooling surface acts as a thermal insulator impeding the effect
of forced air-cooling. This layer needs to be disrupted by turbulent
airflow, which can be created by providing irregular fins and fin
geometries."
http://www.freepatentsonline.com/6729383.html
"at least some said protrusions affect said streaming of said
fluid so as to enhance the turbulence of said streaming of said
fluid, thereby enhancing convective heat transfer from said
object to said fluid."
http://www.overclockers.com/tips90/ -
"Turbulent air cools better. Say, for sake of argument,
you have a simple tube with a fan in the middle. The fan pulls
air from one side of the tube, and blows into the other. If you
have a hot component on the exhaust side of the fan, it will
be more efficiently cooled than on the intake side.
"This is because the air on the exhaust side of the fan
is more turbulent. For lack of a better explanation, the loops
and whorls of turbulent air moving across the surface pick
up more heat. The effective surface area of the object is
increased. (Actually, it was explained to me by saying the
effective surface area of the air is increased.) The total
volume of airflow remains the same, but turbulent air just
cools better."
http://www.begellhouse.com/books/497d60632054f587,6ddfe1a32b58c789.html -
"Turbulent flow is the most common form of motion of liquids
and gases playing the role of the heat-transfer medium in thermal
systems. The complexity of turbulent flow and the importance of
hydrodynamics and heat transfer in practice inspired continuing
research for methods of efficient heat augmentation by the
Lithuanian Energy Institute. The solution of this problem was directly
linked with the determination of the reaction of flow in the boundary
layer to the effect of various factors and heat transfer rate under
given conditions. The investigated factors included elevated degree
of turbulence of the external flow as well as strong acceleration and
turbulization of flow near the wall by surface roughness. The material
in this volume shows that it is possible to control the efficiency of
turbulent transfer when the vortical structure of the turbulent flow is
known."
http://www.cougarlabs.com/cool2.html -
"For convective heat transfer to work well, we need to get the
heat energy out into the flowing coolant. Turbulence will do this
for us."
http://www.ceere.org/beep/docs/FY2002/Turbulent_Flow_in_Enclosure.pdf -
"Comparatively speaking, turbulent flows often lead to higher
transport rate of momentum, energy and mass than laminar flows.
These features are widely made use of in energy systems in industry.
For example, turbulence enhancers such as ribs are added to
cooling systems of turbine blades and microelectronic devices
to create more turbulent motions so that the overall heat transfer
efficiency can be improved."
*TimDaniels*
T
Timothy Daniels
"kornball" jibbered:
The author's conclusion doesn't matter. What matters is that he set
up the experiment and describes the results. And what he described
was a situation wherein increased cooling resulted from increased
turbulence. That he didn't realize that the turbulence increased
is immaterial.
*TimDaniels*
Nope, it's interesting that you dismiss the abilities of the
author in a prior post then try to claim the assessment of
the change is somehow different, and then totally ignore the
invalidity of the "cooling increased" concept from single
point measurements, as well as ignoring that reducing fan
intake rate will reduce turbulence.
The author's conclusion doesn't matter. What matters is that he set
up the experiment and describes the results. And what he described
was a situation wherein increased cooling resulted from increased
turbulence. That he didn't realize that the turbulence increased
is immaterial.
*TimDaniels*
T
Timothy Daniels
kornball said:IF all else were equal, which is not the case.
WTF does *that* mean, "If all else were equal"?
Cooling ALWAYS aids the transfer of heat between
an object and a moving fluid in which the object is
immersed. That applies to both cooling and heating
of the object, depending only on whether the object
is hotter or colder than the fluid.
You can have turbulence, at expense of airflow (which
will raise temps
You assume that any decrease in bulk air flow will
reduce the cooling effect of the passing air. That
depends on the turbulence - which will aid the heat
transfer.
... or at expense of noise. If you don't mind that noise,
Always dodging and weaving. We're talking about
turbulence and cooling. YOU'RE now arguing about noise
to change the subject. Obviously, you realize you can't
squirm out of admitting that turbulence aids cooling.
*TimDaniels*
K
kony
http://www.thermaflo.com/crosscut.shtml
"Turbulent air breaks the stagnant air boundary layers
around the pins and, as a result, enhances the heat sink's
thermal performance."
You seem to have crashed in an infinite loop again.
K
kony
WTF does *that* mean, "If all else were equal"?
It means that for you to understand why all else isn't
equal, you will have to either listen to what you're telling
you and believe there are other variables besides only an
introduction of more turbulence, OR do the tests you'd have
to anyway to prove this idea you have and learn from the
accumulated data.
T
Timothy Daniels
"kornball" wailed:
You can't take the truth repeated for you.
And you still haven't addressed this bulk of evidence:
http://www.thermaflo.com/crosscut.shtml
"Turbulent air breaks the stagnant air boundary layers
around the pins and, as a result, enhances the heat sink's
thermal performance."
http://www.frostytech.com/articleview.cfm?articleID=2001
"To induce turbulence within the fins and improve thermal
transmission between the air and metal, Thermalright have
modified the aluminum fins by adding 'proprietary bent winglets'."
http://sound.westhost.com/heatsinks.htm
"Simple convection is not as effective (even for the same rate
of flow of air), because of the "laminar" flow of air (where the
air at the surface of the heatsink moves slower than that further
away). This effect can be easily seen on a windy day. If you stay
close to a wall or other large area (lying on the ground works too),
it will be noticed that it is less windy than out in the open. Exactly
the same thing happens with heatsinks (but on a somewhat
reduced scale). Creating turbulence is an excellent way to defeat
this process, but this requires fans, and fans are noisy."
http://www.fischerelektronik.de/fischer2002/fischer/Fachb-Act_Rep/kuehlkonzepte/KKoneng_e.htm
"The heat transfer towards the flowing air that can be achieved
with plain fins is relatively restricted. The laminar air flow that
emerges is not sufficient to carry off the heat. Therefore, attempts
are being made to improve heat transfer (fins to air) by producing
more turbulent flow using an appropriate fin geometry."
http://www.hilltech.com/products/uv_components/UV_irradiators.html
"Optimizing cooling efficiency in an LIA is achieved by using
a heatsink-based aluminum reflector, where the material has
a high thermal conductivity and the design maximizes the effects
of surface area and turbulence. Within reason, the more surface
area the better the lamp cooling. Also important is turbulence,
because of the skin effect in cooling. A thin layer of air surrounding
a cooling surface acts as a thermal insulator impeding the effect
of forced air-cooling. This layer needs to be disrupted by turbulent
airflow, which can be created by providing irregular fins and fin
geometries."
http://www.freepatentsonline.com/6729383.html
"at least some said protrusions affect said streaming of said
fluid so as to enhance the turbulence of said streaming of said
fluid, thereby enhancing convective heat transfer from said
object to said fluid."
http://www.overclockers.com/tips90/ -
"Turbulent air cools better. Say, for sake of argument,
you have a simple tube with a fan in the middle. The fan pulls
air from one side of the tube, and blows into the other. If you
have a hot component on the exhaust side of the fan, it will
be more efficiently cooled than on the intake side.
"This is because the air on the exhaust side of the fan
is more turbulent. For lack of a better explanation, the loops
and whorls of turbulent air moving across the surface pick
up more heat. The effective surface area of the object is
increased. (Actually, it was explained to me by saying the
effective surface area of the air is increased.) The total
volume of airflow remains the same, but turbulent air just
cools better."
http://www.begellhouse.com/books/497d60632054f587,6ddfe1a32b58c789.html -
"Turbulent flow is the most common form of motion of liquids
and gases playing the role of the heat-transfer medium in thermal
systems. The complexity of turbulent flow and the importance of
hydrodynamics and heat transfer in practice inspired continuing
research for methods of efficient heat augmentation by the
Lithuanian Energy Institute. The solution of this problem was directly
linked with the determination of the reaction of flow in the boundary
layer to the effect of various factors and heat transfer rate under
given conditions. The investigated factors included elevated degree
of turbulence of the external flow as well as strong acceleration and
turbulization of flow near the wall by surface roughness. The material
in this volume shows that it is possible to control the efficiency of
turbulent transfer when the vortical structure of the turbulent flow is
known."
http://www.cougarlabs.com/cool2.html -
"For convective heat transfer to work well, we need to get the
heat energy out into the flowing coolant. Turbulence will do this
for us."
http://www.ceere.org/beep/docs/FY2002/Turbulent_Flow_in_Enclosure.pdf -
"Comparatively speaking, turbulent flows often lead to higher
transport rate of momentum, energy and mass than laminar flows.
These features are widely made use of in energy systems in industry.
For example, turbulence enhancers such as ribs are added to
cooling systems of turbine blades and microelectronic devices
to create more turbulent motions so that the overall heat transfer
efficiency can be improved."
*TimDaniels*
*TimDaniels*
You seem to have crashed in an infinite loop again.
You can't take the truth repeated for you.
And you still haven't addressed this bulk of evidence:
http://www.thermaflo.com/crosscut.shtml
"Turbulent air breaks the stagnant air boundary layers
around the pins and, as a result, enhances the heat sink's
thermal performance."
http://www.frostytech.com/articleview.cfm?articleID=2001
"To induce turbulence within the fins and improve thermal
transmission between the air and metal, Thermalright have
modified the aluminum fins by adding 'proprietary bent winglets'."
http://sound.westhost.com/heatsinks.htm
"Simple convection is not as effective (even for the same rate
of flow of air), because of the "laminar" flow of air (where the
air at the surface of the heatsink moves slower than that further
away). This effect can be easily seen on a windy day. If you stay
close to a wall or other large area (lying on the ground works too),
it will be noticed that it is less windy than out in the open. Exactly
the same thing happens with heatsinks (but on a somewhat
reduced scale). Creating turbulence is an excellent way to defeat
this process, but this requires fans, and fans are noisy."
http://www.fischerelektronik.de/fischer2002/fischer/Fachb-Act_Rep/kuehlkonzepte/KKoneng_e.htm
"The heat transfer towards the flowing air that can be achieved
with plain fins is relatively restricted. The laminar air flow that
emerges is not sufficient to carry off the heat. Therefore, attempts
are being made to improve heat transfer (fins to air) by producing
more turbulent flow using an appropriate fin geometry."
http://www.hilltech.com/products/uv_components/UV_irradiators.html
"Optimizing cooling efficiency in an LIA is achieved by using
a heatsink-based aluminum reflector, where the material has
a high thermal conductivity and the design maximizes the effects
of surface area and turbulence. Within reason, the more surface
area the better the lamp cooling. Also important is turbulence,
because of the skin effect in cooling. A thin layer of air surrounding
a cooling surface acts as a thermal insulator impeding the effect
of forced air-cooling. This layer needs to be disrupted by turbulent
airflow, which can be created by providing irregular fins and fin
geometries."
http://www.freepatentsonline.com/6729383.html
"at least some said protrusions affect said streaming of said
fluid so as to enhance the turbulence of said streaming of said
fluid, thereby enhancing convective heat transfer from said
object to said fluid."
http://www.overclockers.com/tips90/ -
"Turbulent air cools better. Say, for sake of argument,
you have a simple tube with a fan in the middle. The fan pulls
air from one side of the tube, and blows into the other. If you
have a hot component on the exhaust side of the fan, it will
be more efficiently cooled than on the intake side.
"This is because the air on the exhaust side of the fan
is more turbulent. For lack of a better explanation, the loops
and whorls of turbulent air moving across the surface pick
up more heat. The effective surface area of the object is
increased. (Actually, it was explained to me by saying the
effective surface area of the air is increased.) The total
volume of airflow remains the same, but turbulent air just
cools better."
http://www.begellhouse.com/books/497d60632054f587,6ddfe1a32b58c789.html -
"Turbulent flow is the most common form of motion of liquids
and gases playing the role of the heat-transfer medium in thermal
systems. The complexity of turbulent flow and the importance of
hydrodynamics and heat transfer in practice inspired continuing
research for methods of efficient heat augmentation by the
Lithuanian Energy Institute. The solution of this problem was directly
linked with the determination of the reaction of flow in the boundary
layer to the effect of various factors and heat transfer rate under
given conditions. The investigated factors included elevated degree
of turbulence of the external flow as well as strong acceleration and
turbulization of flow near the wall by surface roughness. The material
in this volume shows that it is possible to control the efficiency of
turbulent transfer when the vortical structure of the turbulent flow is
known."
http://www.cougarlabs.com/cool2.html -
"For convective heat transfer to work well, we need to get the
heat energy out into the flowing coolant. Turbulence will do this
for us."
http://www.ceere.org/beep/docs/FY2002/Turbulent_Flow_in_Enclosure.pdf -
"Comparatively speaking, turbulent flows often lead to higher
transport rate of momentum, energy and mass than laminar flows.
These features are widely made use of in energy systems in industry.
For example, turbulence enhancers such as ribs are added to
cooling systems of turbine blades and microelectronic devices
to create more turbulent motions so that the overall heat transfer
efficiency can be improved."
*TimDaniels*
*TimDaniels*
T
Timothy Daniels
kornball said:"Timothy Daniels" asked:
It means that for you to understand why all else isn't
equal, you will have to either listen to what you're telling
you and believe there are other variables besides only an
introduction of more turbulence, OR do the tests you'd have
to anyway to prove this idea you have and learn from the
accumulated data.
The experiment has been adequately described in
BenchTest.com . The results have been described
in BenchTest.com . As expected, though, you denigrate
the experiment because it doesn't prove what you must
believe. No water will satisfy a horse which refuses to
drink.
*TimDaniels*
K
kony
You can't take the truth repeated for you.
So essentially you've decided to waste news server bandwidth
by reposting the same text over and over again. How truely
productive of you!
K
kony
The experiment has been adequately described in
BenchTest.com . The results have been described
in BenchTest.com . As expected, though, you denigrate
the experiment because it doesn't prove what you must
believe. No water will satisfy a horse which refuses to
drink.
We already know why that test doesn't support your claim.
M
meow2222
Isn't it interesting, then, that when air intake through the fan was
restricted, the cooling increased.
Whats interesting is that you believe that the cooling was increased.
NT
T
Timothy Daniels
kornball said:So essentially you've decided to waste news server bandwidth
by reposting the same text over and over again. How truely
productive of you!
I'm just waiting for the laugh that will come when you
eventually try to address the plethora of evidence
that says turbulence should be generated to improve
the cooling effect of air flow, not suppressed as you
would have it.
Tell us again how all this is wrong:
http://www.thermaflo.com/crosscut.shtml
"Turbulent air breaks the stagnant air boundary layers
around the pins and, as a result, enhances the heat sink's
thermal performance."
http://www.frostytech.com/articleview.cfm?articleID=2001
"To induce turbulence within the fins and improve thermal
transmission between the air and metal, Thermalright have
modified the aluminum fins by adding 'proprietary bent winglets'."
http://sound.westhost.com/heatsinks.htm
"Simple convection is not as effective (even for the same rate
of flow of air), because of the "laminar" flow of air (where the
air at the surface of the heatsink moves slower than that further
away). This effect can be easily seen on a windy day. If you stay
close to a wall or other large area (lying on the ground works too),
it will be noticed that it is less windy than out in the open. Exactly
the same thing happens with heatsinks (but on a somewhat
reduced scale). Creating turbulence is an excellent way to defeat
this process, but this requires fans, and fans are noisy."
http://www.fischerelektronik.de/fischer2002/fischer/Fachb-Act_Rep/kuehlkonzepte/KKoneng_e.htm
"The heat transfer towards the flowing air that can be achieved
with plain fins is relatively restricted. The laminar air flow that
emerges is not sufficient to carry off the heat. Therefore, attempts
are being made to improve heat transfer (fins to air) by producing
more turbulent flow using an appropriate fin geometry."
http://www.hilltech.com/products/uv_components/UV_irradiators.html
"Optimizing cooling efficiency in an LIA is achieved by using
a heatsink-based aluminum reflector, where the material has
a high thermal conductivity and the design maximizes the effects
of surface area and turbulence. Within reason, the more surface
area the better the lamp cooling. Also important is turbulence,
because of the skin effect in cooling. A thin layer of air surrounding
a cooling surface acts as a thermal insulator impeding the effect
of forced air-cooling. This layer needs to be disrupted by turbulent
airflow, which can be created by providing irregular fins and fin
geometries."
http://www.freepatentsonline.com/6729383.html
"at least some said protrusions affect said streaming of said
fluid so as to enhance the turbulence of said streaming of said
fluid, thereby enhancing convective heat transfer from said
object to said fluid."
http://www.overclockers.com/tips90/ -
"Turbulent air cools better. Say, for sake of argument,
you have a simple tube with a fan in the middle. The fan pulls
air from one side of the tube, and blows into the other. If you
have a hot component on the exhaust side of the fan, it will
be more efficiently cooled than on the intake side.
"This is because the air on the exhaust side of the fan
is more turbulent. For lack of a better explanation, the loops
and whorls of turbulent air moving across the surface pick
up more heat. The effective surface area of the object is
increased. (Actually, it was explained to me by saying the
effective surface area of the air is increased.) The total
volume of airflow remains the same, but turbulent air just
cools better."
http://www.begellhouse.com/books/497d60632054f587,6ddfe1a32b58c789.html -
"Turbulent flow is the most common form of motion of liquids
and gases playing the role of the heat-transfer medium in thermal
systems. The complexity of turbulent flow and the importance of
hydrodynamics and heat transfer in practice inspired continuing
research for methods of efficient heat augmentation by the
Lithuanian Energy Institute. The solution of this problem was directly
linked with the determination of the reaction of flow in the boundary
layer to the effect of various factors and heat transfer rate under
given conditions. The investigated factors included elevated degree
of turbulence of the external flow as well as strong acceleration and
turbulization of flow near the wall by surface roughness. The material
in this volume shows that it is possible to control the efficiency of
turbulent transfer when the vortical structure of the turbulent flow is
known."
http://www.cougarlabs.com/cool2.html -
"For convective heat transfer to work well, we need to get the
heat energy out into the flowing coolant. Turbulence will do this
for us."
http://www.ceere.org/beep/docs/FY2002/Turbulent_Flow_in_Enclosure.pdf -
"Comparatively speaking, turbulent flows often lead to higher
transport rate of momentum, energy and mass than laminar flows.
These features are widely made use of in energy systems in industry.
For example, turbulence enhancers such as ribs are added to
cooling systems of turbine blades and microelectronic devices
to create more turbulent motions so that the overall heat transfer
efficiency can be improved."
*TimDaniels*
T
Timothy Daniels
Whats interesting is that you believe that the cooling was increased.
The experimenter observed that the temperature in the case
went down. That means the cooling increased.
*TimDaniels*
K
kony
I'm just waiting for the laugh that will come ...
Well hell Tim, why didn't you just say so in the first
place!
LOL
.... and with that, I think this thread is done. Have fun
with it Tim.
T
Timothy Daniels
kony said:We already know why that test doesn't support your claim.
"We already know why" is an unsubstantiated statement.
*TimDaniels*
T
Timothy Daniels
"kornball" coughed and sputtered:
Have fun answering these:
http://www.thermaflo.com/crosscut.shtml
"Turbulent air breaks the stagnant air boundary layers
around the pins and, as a result, enhances the heat sink's
thermal performance."
http://www.frostytech.com/articleview.cfm?articleID=2001
"To induce turbulence within the fins and improve thermal
transmission between the air and metal, Thermalright have
modified the aluminum fins by adding 'proprietary bent winglets'."
http://sound.westhost.com/heatsinks.htm
"Simple convection is not as effective (even for the same rate
of flow of air), because of the "laminar" flow of air (where the
air at the surface of the heatsink moves slower than that further
away). This effect can be easily seen on a windy day. If you stay
close to a wall or other large area (lying on the ground works too),
it will be noticed that it is less windy than out in the open. Exactly
the same thing happens with heatsinks (but on a somewhat
reduced scale). Creating turbulence is an excellent way to defeat
this process, but this requires fans, and fans are noisy."
http://www.fischerelektronik.de/fischer2002/fischer/Fachb-Act_Rep/kuehlkonzepte/KKoneng_e.htm
"The heat transfer towards the flowing air that can be achieved
with plain fins is relatively restricted. The laminar air flow that
emerges is not sufficient to carry off the heat. Therefore, attempts
are being made to improve heat transfer (fins to air) by producing
more turbulent flow using an appropriate fin geometry."
http://www.hilltech.com/products/uv_components/UV_irradiators.html
"Optimizing cooling efficiency in an LIA is achieved by using
a heatsink-based aluminum reflector, where the material has
a high thermal conductivity and the design maximizes the effects
of surface area and turbulence. Within reason, the more surface
area the better the lamp cooling. Also important is turbulence,
because of the skin effect in cooling. A thin layer of air surrounding
a cooling surface acts as a thermal insulator impeding the effect
of forced air-cooling. This layer needs to be disrupted by turbulent
airflow, which can be created by providing irregular fins and fin
geometries."
http://www.freepatentsonline.com/6729383.html
"at least some said protrusions affect said streaming of said
fluid so as to enhance the turbulence of said streaming of said
fluid, thereby enhancing convective heat transfer from said
object to said fluid."
http://www.overclockers.com/tips90/ -
"Turbulent air cools better. Say, for sake of argument,
you have a simple tube with a fan in the middle. The fan pulls
air from one side of the tube, and blows into the other. If you
have a hot component on the exhaust side of the fan, it will
be more efficiently cooled than on the intake side.
"This is because the air on the exhaust side of the fan
is more turbulent. For lack of a better explanation, the loops
and whorls of turbulent air moving across the surface pick
up more heat. The effective surface area of the object is
increased. (Actually, it was explained to me by saying the
effective surface area of the air is increased.) The total
volume of airflow remains the same, but turbulent air just
cools better."
http://www.begellhouse.com/books/497d60632054f587,6ddfe1a32b58c789.html -
"Turbulent flow is the most common form of motion of liquids
and gases playing the role of the heat-transfer medium in thermal
systems. The complexity of turbulent flow and the importance of
hydrodynamics and heat transfer in practice inspired continuing
research for methods of efficient heat augmentation by the
Lithuanian Energy Institute. The solution of this problem was directly
linked with the determination of the reaction of flow in the boundary
layer to the effect of various factors and heat transfer rate under
given conditions. The investigated factors included elevated degree
of turbulence of the external flow as well as strong acceleration and
turbulization of flow near the wall by surface roughness. The material
in this volume shows that it is possible to control the efficiency of
turbulent transfer when the vortical structure of the turbulent flow is
known."
http://www.cougarlabs.com/cool2.html -
"For convective heat transfer to work well, we need to get the
heat energy out into the flowing coolant. Turbulence will do this
for us."
http://www.ceere.org/beep/docs/FY2002/Turbulent_Flow_in_Enclosure.pdf -
"Comparatively speaking, turbulent flows often lead to higher
transport rate of momentum, energy and mass than laminar flows.
These features are widely made use of in energy systems in industry.
For example, turbulence enhancers such as ribs are added to
cooling systems of turbine blades and microelectronic devices
to create more turbulent motions so that the overall heat transfer
efficiency can be improved."
*TimDaniels*
... and with that, I think this thread is done. Have fun
with it Tim.
Have fun answering these:
http://www.thermaflo.com/crosscut.shtml
"Turbulent air breaks the stagnant air boundary layers
around the pins and, as a result, enhances the heat sink's
thermal performance."
http://www.frostytech.com/articleview.cfm?articleID=2001
"To induce turbulence within the fins and improve thermal
transmission between the air and metal, Thermalright have
modified the aluminum fins by adding 'proprietary bent winglets'."
http://sound.westhost.com/heatsinks.htm
"Simple convection is not as effective (even for the same rate
of flow of air), because of the "laminar" flow of air (where the
air at the surface of the heatsink moves slower than that further
away). This effect can be easily seen on a windy day. If you stay
close to a wall or other large area (lying on the ground works too),
it will be noticed that it is less windy than out in the open. Exactly
the same thing happens with heatsinks (but on a somewhat
reduced scale). Creating turbulence is an excellent way to defeat
this process, but this requires fans, and fans are noisy."
http://www.fischerelektronik.de/fischer2002/fischer/Fachb-Act_Rep/kuehlkonzepte/KKoneng_e.htm
"The heat transfer towards the flowing air that can be achieved
with plain fins is relatively restricted. The laminar air flow that
emerges is not sufficient to carry off the heat. Therefore, attempts
are being made to improve heat transfer (fins to air) by producing
more turbulent flow using an appropriate fin geometry."
http://www.hilltech.com/products/uv_components/UV_irradiators.html
"Optimizing cooling efficiency in an LIA is achieved by using
a heatsink-based aluminum reflector, where the material has
a high thermal conductivity and the design maximizes the effects
of surface area and turbulence. Within reason, the more surface
area the better the lamp cooling. Also important is turbulence,
because of the skin effect in cooling. A thin layer of air surrounding
a cooling surface acts as a thermal insulator impeding the effect
of forced air-cooling. This layer needs to be disrupted by turbulent
airflow, which can be created by providing irregular fins and fin
geometries."
http://www.freepatentsonline.com/6729383.html
"at least some said protrusions affect said streaming of said
fluid so as to enhance the turbulence of said streaming of said
fluid, thereby enhancing convective heat transfer from said
object to said fluid."
http://www.overclockers.com/tips90/ -
"Turbulent air cools better. Say, for sake of argument,
you have a simple tube with a fan in the middle. The fan pulls
air from one side of the tube, and blows into the other. If you
have a hot component on the exhaust side of the fan, it will
be more efficiently cooled than on the intake side.
"This is because the air on the exhaust side of the fan
is more turbulent. For lack of a better explanation, the loops
and whorls of turbulent air moving across the surface pick
up more heat. The effective surface area of the object is
increased. (Actually, it was explained to me by saying the
effective surface area of the air is increased.) The total
volume of airflow remains the same, but turbulent air just
cools better."
http://www.begellhouse.com/books/497d60632054f587,6ddfe1a32b58c789.html -
"Turbulent flow is the most common form of motion of liquids
and gases playing the role of the heat-transfer medium in thermal
systems. The complexity of turbulent flow and the importance of
hydrodynamics and heat transfer in practice inspired continuing
research for methods of efficient heat augmentation by the
Lithuanian Energy Institute. The solution of this problem was directly
linked with the determination of the reaction of flow in the boundary
layer to the effect of various factors and heat transfer rate under
given conditions. The investigated factors included elevated degree
of turbulence of the external flow as well as strong acceleration and
turbulization of flow near the wall by surface roughness. The material
in this volume shows that it is possible to control the efficiency of
turbulent transfer when the vortical structure of the turbulent flow is
known."
http://www.cougarlabs.com/cool2.html -
"For convective heat transfer to work well, we need to get the
heat energy out into the flowing coolant. Turbulence will do this
for us."
http://www.ceere.org/beep/docs/FY2002/Turbulent_Flow_in_Enclosure.pdf -
"Comparatively speaking, turbulent flows often lead to higher
transport rate of momentum, energy and mass than laminar flows.
These features are widely made use of in energy systems in industry.
For example, turbulence enhancers such as ribs are added to
cooling systems of turbine blades and microelectronic devices
to create more turbulent motions so that the overall heat transfer
efficiency can be improved."
*TimDaniels*
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