CFD Online Logo CFD Online URL
www.cfd-online.com
[Sponsors]
Home > Forums > General Forums > Main CFD Forum

What is specific heat really means

Register Blogs Community New Posts Updated Threads Search

Like Tree5Likes
  • 1 Post By mouli1991
  • 1 Post By immortality
  • 1 Post By RodriguezFatz
  • 2 Post By immortality

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
Old   April 19, 2013, 00:27
Post What is specific heat really means
  #1
New Member
 
Sayee chandrasekara mouli
Join Date: Mar 2012
Posts: 21
Rep Power: 14
mouli1991 is on a distinguished road
Send a message via Yahoo to mouli1991
I have confusion from my school days that why there is specific for everything..like specific heat,temp etc..pls help me with really meaning
immortality likes this.
mouli1991 is offline   Reply With Quote

Old   April 19, 2013, 02:48
Default
  #2
Senior Member
 
immortality's Avatar
 
Ehsan
Join Date: Oct 2012
Location: Iran
Posts: 2,208
Rep Power: 26
immortality is on a distinguished road
a wisely question.
Well,i think maybe several reasons be in existence each different in different cases.
I have not heard specific temperature(in real gas theory?)
But in some cases we want only dimensionless numbers so that probably simplifies our work during calculation or make it easier when do experiments or compare related cases,like specific length that can be the ratio of two lengths.
Or a quantity in a period of time or divided by a quantity of mass,like specific heat(J/kg.K).
In some cases maybe we only want a name for a concept.as an example specific volume is only reciprocal of density.
Want anyone contribute in this argument or my speech is complete?
mouli1991 likes this.
immortality is offline   Reply With Quote

Old   April 19, 2013, 05:09
Thumbs up Oh yeah..yes
  #3
New Member
 
Sayee chandrasekara mouli
Join Date: Mar 2012
Posts: 21
Rep Power: 14
mouli1991 is on a distinguished road
Send a message via Yahoo to mouli1991
However I still cant understand...You said some used for concept sake..your example is j/kg k..and why do we need to do that...like specific volume.
mouli1991 is offline   Reply With Quote

Old   April 19, 2013, 06:22
Default
  #4
Senior Member
 
RodriguezFatz's Avatar
 
Philipp
Join Date: Jun 2011
Location: Germany
Posts: 1,297
Rep Power: 26
RodriguezFatz will become famous soon enough
You can have an amount of heat Q stored inside a block of 2.3kg metal. Now, proportional to this heat Q is the heat capacity of the 2.3kg block C~Q. But this is just the heat capacity of a 2.3kg block. If you want to know the ability of that metal to store heat, you divide C by the mass of the block. Than you get the specific heat capacity. This is a material's property an not any longer the property of any special sized block. So if you are interested in material properties you need these "specific" values.
I guess you can use this explanation for most of the "specific ..." cases.
mouli1991 likes this.
__________________
The skeleton ran out of shampoo in the shower.
RodriguezFatz is offline   Reply With Quote

Old   April 19, 2013, 07:42
Post
  #5
New Member
 
Sayee chandrasekara mouli
Join Date: Mar 2012
Posts: 21
Rep Power: 14
mouli1991 is on a distinguished road
Send a message via Yahoo to mouli1991
Yes now explain specific volume.is the sa
me concept as specific heat
..specific volume also material properties
mouli1991 is offline   Reply With Quote

Old   April 19, 2013, 07:49
Default
  #6
Senior Member
 
RodriguezFatz's Avatar
 
Philipp
Join Date: Jun 2011
Location: Germany
Posts: 1,297
Rep Power: 26
RodriguezFatz will become famous soon enough
Sure... volume of a 0.1m cube of water is 1e-3m^3 or just 1 liter. The mass is about 1 kg. The materials property is volume per mass = specific volume. It's always the same value for water, whether you take any cube, sphere or whatever.
__________________
The skeleton ran out of shampoo in the shower.
RodriguezFatz is offline   Reply With Quote

Old   April 19, 2013, 09:21
Post
  #7
New Member
 
Sayee chandrasekara mouli
Join Date: Mar 2012
Posts: 21
Rep Power: 14
mouli1991 is on a distinguished road
Send a message via Yahoo to mouli1991
So to find the capacity of 1 cubic volume of liquid to store is specific volume...like ah ...heat storing capacity of a metal..volume/mass
Am I got it correctly..
mouli1991 is offline   Reply With Quote

Old   April 19, 2013, 10:08
Default
  #8
Senior Member
 
immortality's Avatar
 
Ehsan
Join Date: Oct 2012
Location: Iran
Posts: 2,208
Rep Power: 26
immortality is on a distinguished road
well always its not related to property of a material.
like specific enthalpy is enthalpy per mass flow rate of fluid(1kg/s for example) or specific work(specific work=work/m_dot)that is related to flow of fluid(enthalpy that 1kg of a fluid transfers in 1 second or work 1kg of a fluid does or is done on it in 1s) not the material.but in overall it is correct.
totally can say when we want to know how much a quantity we have per length,mass or mass flow rate we use the expression of specific xxx.
RodriguezFatz and mouli1991 like this.

Last edited by immortality; April 19, 2013 at 11:48.
immortality is offline   Reply With Quote

Old   April 19, 2013, 10:39
Smile
  #9
New Member
 
Sayee chandrasekara mouli
Join Date: Mar 2012
Posts: 21
Rep Power: 14
mouli1991 is on a distinguished road
Send a message via Yahoo to mouli1991
Yep I got that...thank you..specific always to measure quantity and capability of what we take..that's so specific explanation
mouli1991 is offline   Reply With Quote

Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
mass flow in is not equal to mass flow out saii CFX 12 March 19, 2018 05:21
Water subcooled boiling Attesz CFX 7 January 5, 2013 03:32
Constant velocity of the material Sas CFX 15 July 13, 2010 08:56
The effective specific heat and effective density azbr Siemens 0 March 20, 2008 09:28
Integral specific heat Steve Amphlett Main CFD Forum 0 August 25, 2000 09:51


All times are GMT -4. The time now is 23:12.