Talk:Thermal conductance and resistance

message: Here it says
    RθJC = 1.5 K/W (for a typical TO-220 package)
    RθB = 0.1 K/W (a typical value for an elastomer heat-transfer pad for a TO-220 package)
I think the values ar more like 100K/W - 10K/W. Here is an example http://www.ortodoxism.ro/datasheets/philips/BD139-16.pdf I'm trying to find one that has those properties.
--(unsigned edit was by ) Zuperman  2007-05-30T09:44:01 
No, 1.5K/W is OK:
http://www.st.com/stonline/products/literature/ds/10073/stb200nf04.pdf
I've seen a TO-220 regulator one with 3K/W also. The one in BS129-16.pdf has a lower power case style.
Kallog 13:24, 24 June 2007 (UTC)
thread_title: Thermal resistance

message: There's been lots of cleanup since 2006 - is it time to remove the cleanup tag?
It looks pretty good to me. --Lexein (talk) 22:22, 19 March 2010 (UTC)
replies: text: I think the example calculation section is still over complicated. But yea apart from that. Kallog (talk) 01:49, 20 March 2010 (UTC)
replies: text: Agreed. That cleanup tag was a hit & run - the user didn't make any edits. --Lexein (talk) 02:23, 20 March 2010 (UTC)
thread_title: Cleanup tag status

message: The formula in the example does not match the formula with numbers substituted. The latter doesn't have deltaThs but has Rha. Also the concept of deltaThs is not clear. Hoemaco (talk) 07:27, 5 April 2011 (UTC)
replies: text: Agreed. DeltaThs from the formula is not in the example.  More importantly, Deltahs shouldn't be in the equations anyway, as this is accounted for by Q*Rha (i.e. = the temperature drop across the heatsink). Comment that "THS appears to be undefined." in earlier paragraph may be eluding to this.  — Preceding unsigned comment added by ASearcher (talk • contribs) 19:14, 20 March 2013 (UTC)
thread_title:  example confused 

message: Can anyone tell me why meters squared are included?
Keeping them would make calculations & understanding
 so much easier.
But nobody else does that
 except the thermal resistance page & the thermal conduction page.
The thermal conductivity page does not have meters squared
 for thermal resistance or thermal conductance.
77.2.97.53 (talk) 02:00, 4 July 2014 (UTC)
thread_title:  Units are not consistent 

message: 'Thermal insulance ... is the thermal resistance of unit area of a material.' appears to imply 'per unit area' which is untrue: it is the inverse of that.  Would this be better as 'the area of material for one unit of power to flow for each unit of temperature difference'? SciberDoc (talk) 09:49, 19 January 2023 (UTC)
thread_title:  Insulance, R-value 

message: :The following is a closed discussion of a requested move. Please do not modify it. Subsequent comments should be made in a new section on the talk page. Editors desiring to contest the closing decision should consider a move review after discussing it on the closer's talk page. No further edits should be made to this discussion.
The result of the move request was: moved. (closed by non-admin page mover) — MaterialWorks 14:34, 9 October 2023 (UTC)
thread_title:  Requested move 2 October 2023 

message: ====Thermal Resistance vs Thermal Resistivity====
*Thermal Resistance (R) is a measure of how a material or an object opposes the flow of heat. It is expressed in units like Kelvin per Watt (K/W) and indicates how much temperature difference (in Kelvin) is required to transfer a unit of heat energy (in Watts) through the material or object. Lower thermal resistance means better heat conduction.
*Thermal Resistivity (ρ) is a property of a material that quantifies its inherent resistance to heat flow. It is expressed in units like Kelvin meter per Watt (K·m/W). Thermal resistivity is an intrinsic property of a material, whereas thermal resistance depends on the geometry and thickness of the material. Higher thermal resistivity means poorer heat conduction.
====Thermal Conductivity vs Thermal Conductance====
*Thermal Conductivity (κ) is a material property that measures how well a material conducts heat. It is expressed in units like Watts per meter-Kelvin (W/(m·K)). It is a characteristic of the material itself and does not depend on the size or shape of the object. Materials with higher thermal conductivity transfer heat more efficiently.
*Thermal Conductance (C) is a measure of how well a specific object or assembly of materials conducts heat. It is expressed in units like Watts per Kelvin (W/K). Thermal conductance takes into account both the material's thermal conductivity and the object's dimensions. It quantifies the ability of an object to conduct heat under given conditions.
In summary, thermal conductivity and thermal conductance are related but represent different aspects of heat transfer – one is a material property, and the other is a property of an object or assembly of materials. Jeaucques Quœure (talk) 15:52, 4 October 2023 (UTC)
thread_title: Explanation

message: *Thermal Conductivity (κ) is a material property that measures how well a material conducts heat. It is expressed in units like Watts per meter-Kelvin (W/(m·K)). It is a characteristic of the material itself and does not depend on the size or shape of the object. Materials with higher thermal conductivity transfer heat more efficiently.
*Thermal Conductance (C) is a measure of how well a specific object or assembly of materials conducts heat. It is expressed in units like Watts per Kelvin (W/K). Thermal conductance takes into account both the material's thermal conductivity and the object's dimensions. It quantifies the ability of an object to conduct heat under given conditions.
In summary, thermal conductivity and thermal conductance are related but represent different aspects of heat transfer – one is a material property, and the other is a property of an object or assembly of materials. Jeaucques Quœure (talk) 15:52, 4 October 2023 (UTC)
thread_title: Thermal Conductivity vs Thermal Conductance

message: Why are the dimensions given for Thermal Resistance and Conductance shown to be the same?  One should be the invert of the other. I believe this is the correct analysis: C = L2 M T-3 Θ-1 109.158.34.144 (talk) 11:53, 9 January 2024 (UTC)
replies: text: The dimensions were generated automatically from wikidata. I think now should be correct.--ReyHahn (talk) 13:14, 9 January 2024 (UTC)
thread_title:  Dimensional Analysis