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Heat Energy transfer falls under the Law of Thermodynamics. This is defined as the internal energy (E) which is equal to the change of heat transfer (Q) ''into'' a system and work (W) ''done by'' the system.  When heat is removed from a system it results with a negative answer, and when heat is added to a system allows for a positive transfer of heat and thus a positive answer. Heat can not be stored like Potential energy, due to the process that is needed; thus resulting in Kinetic energy.  Due to this many different arrangements of the system are able to exist.
Heat Energy transfer falls under the Law of Thermodynamics. This is defined as the internal energy (E) which is equal to the change of heat transfer (Q) ''into'' a system and work (W) ''done by'' the system.  When heat is removed from a system it results with a negative answer, and when heat is added to a system allows for a positive transfer of heat and thus a positive answer. Heat can not be stored like Potential energy, due to the process that is needed; thus resulting in Kinetic energy.  Due to this many different arrangements of the system are able to exist.


==Second Law==
==Specific Heat==


The second law states that there is another useful variable of heat, entropy (S).  Entropy can be described as the disorder or chaos of a system, but in physics, we will just refer to it as another variable like enthalpy or temperature. For any given physical process, the combined entropy of a system and the environment remains a constant if the process can be reversed.  The second law also states that if the physical process is irreversible, the combined entropy of the system and the environment must increase.  Therefore, the final entropy must be greater than the initial entropy.
With liquids and solids that are changing temperature, there is a specific heat associated with a temperature change. This means that the specific heat is variable upon the mass of an object, the change in time as well as the material that is absorbing or expelling heat.  


===Mathematical Models===


delta S = delta Q/T
===Specific Heat Formulas===
Sf = Si (reversible process)
Sf > Si (irreversible process)


===Examples===
Q= m*c *(change in time)


'''Reversible process''': Ideally forcing a flow through a constricted pipe, where there are no boundary layers. As the flow moves through the constriction, the pressure, volume and temperature change, but they return to their normal values once they hit the downstream.  This return to the variables' original values allows there to be no change in entropy.  It is often known as an isentropic process. 
Within this equation heat is found by mass* "C" which is a constant multiplied by the change in time.
 
'''Irreversible process''': When a hot object and cold object are put in contact with each other, eventually the heat from the hot object will transfer to the cold object and the two will reach the same temperature and stay constant at that temperature, reaching equilibrium.  However, once those objects are separated, they will remain at that equilibrium temperature until something else acts upon it.  The objects do not go back to their original temperatures so there is a change in entropy.


==Connectedness==
==Connectedness==
#How is this topic connected to something that you are interested in?
#How is this topic connected to something that you are interested in?
            This topic is interesting to me because thermal heat was the most enjoyed topic that was studied all semester.
#How is it connected to your major?
#How is it connected to your major?
            My major is Building Construction and this is related because we calculate the change in heat within expansion joints for concrete.
#Is there an interesting industrial application?
#Is there an interesting industrial application?
            The application applied relates to all materials used in construction with expansion and contraction.


==History==
==History==


Thermodynamics was brought up as a science in the 18th and 19th centuries. However, it was first brought up by Galilei, who introduced the concept of temperature and invented the first thermometer.  G. Black first introduced the word 'thermodynamics'.  Later, G. Wilke introduced another unit of measurement known as the calorie that measures heat.  The idea of thermodynamics was brought up by Nicolas Leonard Sadi Carnot. He is often known as "the father of thermodynamics".  It all began with the development of the steam engine during the Industrial Revolution. He devised an ideal cycle of operation.  During his observations and experimentations, he had the incorrect notion that heat is conserved, however he was able to lay down theorems that led to the development of thermodynamics.  In the 20th century, the science of thermodynamics became a conventional term and a basic division of physics.  Thermodynamics dealt with the study of general properties of physical systems under equilibrium and the conditions necessary to obtain equilibrium.
The idea of thermodynamics was idealized during the late 17th century, but was truly recognized during the 18th and 19th centuries. Jean Baptiste Biot (1774-1862) worked on the analysis of heat conduction, however unsuccessful. Then Baron Jean Baptiste Joseph Fourier (1768-1830) continued the work of Boit and completed his(Fourier's) masterpiece which was known as the mathematical theory of heat conduction which was stated within  Theorie Analytique de la Chaleur (1822). "Around 1850 Rudolf Clausius and William Thomson (Kelvin) stated both the First Law - that total energy is conserved - and the Second Law of Thermodynamics. The Second Law was originally formulated in terms of the fact that heat does not spontaneously flow from a colder body to a hotter." The terminology, "thermodynamics", was not created until the year 1854, during this time a British mathematician and physicist, William Thomson (Lord Kelvin) created the terminology thermo-dynamics when he wrote a paper upon On the Dynamical Theory of Heat.


== See also ==
== See also ==
Are there related topics or categories in this wiki resource for the curious reader to explore?  How does this topic fit into that context?
===Further reading===
Books, Articles or other print media on this topic


===External links===
===External links===


Internet resources on this topic
http://www.seas.ucla.edu/jht/pioneers/pioneers.html
http://teacher.pas.rochester.edu/phy121/lecturenotes/Chapter17/Chapter17.html


==References==
==References==
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https://en.wikipedia.org/wiki/Heat_transfer
https://en.wikipedia.org/wiki/Heat_transfer
http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/heatra.html
http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/heatra.html
https://s-media-cache-ak0.pinimg.com/736x/2a/5e/d6/2a5ed64011dd8c93ecf6bdccca3ba537.jpg
https://www.youtube.com/watch?v=pnVVJfUMkAo


[[Category:Thermal Energy]]
[[Category:Thermal Energy]]

Latest revision as of 21:38, 5 December 2015

Thermal Energy

This topics focuses on the energy and work of a system. Energy transfer is one of the fundamental principals of Physics, thermal energy falls under this category. This type of energy falls under the abbreviation of Q which stands for the heat that is expelled from an object once a reaction or kinetic energy is transferred; as well as the movement of tiny particles within the object. There are three forms of Thermal Energy: Conduction, Convection and Radiation. Conduction is the transfer of heat energy though collisions between adjacent molecules. Convection is the transfer of heat through motion of a fluid such as air or water; when the fluid is heated it is caused to move away from the source of heat, therefore carrying the heat energy with it. Radiation is the transfer of heat through waves or particles through a material or space.

Definitions

E(total) = delta K + delta U + Rest Energy [1]

Units

All types of energy are expressed in Joules. Thermal Energy(Heat) is no different from the other forms of energy with the expression of units; therefore Thermal Energy(Heat) is also expressed in Joules as well.

A Computational Model

You are able to view the transfer of heat through the link provided.[2] This link gives credit to the author, Andi Lucas; it is a video I found interesting and entertaining, however I did not create the video.

First Law

Heat Energy transfer falls under the Law of Thermodynamics. This is defined as the internal energy (E) which is equal to the change of heat transfer (Q) into a system and work (W) done by the system. When heat is removed from a system it results with a negative answer, and when heat is added to a system allows for a positive transfer of heat and thus a positive answer. Heat can not be stored like Potential energy, due to the process that is needed; thus resulting in Kinetic energy. Due to this many different arrangements of the system are able to exist.

Specific Heat

With liquids and solids that are changing temperature, there is a specific heat associated with a temperature change. This means that the specific heat is variable upon the mass of an object, the change in time as well as the material that is absorbing or expelling heat.


Specific Heat Formulas

Q= m*c *(change in time)

Within this equation heat is found by mass* "C" which is a constant multiplied by the change in time.

Connectedness

  1. How is this topic connected to something that you are interested in?
           This topic is interesting to me because thermal heat was the most enjoyed topic that was studied all semester.
  1. How is it connected to your major?
            My major is Building Construction and this is related because we calculate the change in heat within expansion joints for concrete.
  1. Is there an interesting industrial application?
            The application applied relates to all materials used in construction with expansion and contraction.

History

The idea of thermodynamics was idealized during the late 17th century, but was truly recognized during the 18th and 19th centuries. Jean Baptiste Biot (1774-1862) worked on the analysis of heat conduction, however unsuccessful. Then Baron Jean Baptiste Joseph Fourier (1768-1830) continued the work of Boit and completed his(Fourier's) masterpiece which was known as the mathematical theory of heat conduction which was stated within Theorie Analytique de la Chaleur (1822). "Around 1850 Rudolf Clausius and William Thomson (Kelvin) stated both the First Law - that total energy is conserved - and the Second Law of Thermodynamics. The Second Law was originally formulated in terms of the fact that heat does not spontaneously flow from a colder body to a hotter." The terminology, "thermodynamics", was not created until the year 1854, during this time a British mathematician and physicist, William Thomson (Lord Kelvin) created the terminology thermo-dynamics when he wrote a paper upon On the Dynamical Theory of Heat.

See also

External links

http://www.seas.ucla.edu/jht/pioneers/pioneers.html http://teacher.pas.rochester.edu/phy121/lecturenotes/Chapter17/Chapter17.html

References

Georgia Tech Physics Department Example Page http://physics.bu.edu/~duffy/py105/notes/Heattransfer.html https://en.wikipedia.org/wiki/Heat_transfer http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/heatra.html https://s-media-cache-ak0.pinimg.com/736x/2a/5e/d6/2a5ed64011dd8c93ecf6bdccca3ba537.jpg https://www.youtube.com/watch?v=pnVVJfUMkAo

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