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Specific Heat Capacity. Chu Wei Xiang (3S311) Kenneth Tan (3S209) Tan Yu Yang (3S323). Specific Heat Capacity. The amount of heat energy required to raise the temperature of a unit mass (of the body) by one degree, without going through a change in state. Specific Heat Capacity.
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Specific Heat Capacity Chu Wei Xiang (3S311) Kenneth Tan (3S209) Tan Yu Yang (3S323)
Specific Heat Capacity • The amount of heat energy required to raise the temperature of a unit mass (of the body) by one degree, without going through a change in state
Specific Heat Capacity Heat or thermal energy absorbed or released (in J) Q c = m × ∆T Change in temperature (final temperature – initial temperature) [in K or °C] Specific heat capacity (in Jkg-1K-1 or Jkg-1 °C -1 ) Mass of the substance (in kg)
Specific heat capacity • Larger amount of heat energy is required to raise the temperature of a substance with high specific heat capacity than one with low specific heat capacity. • The specific heat of almost any substance can be measured, these includes chemical elements, compounds, alloys, solutions etc.
Factor affecting specific heat capacity • Impurities: • For alloys, small impurity concentrations can greatly affect the specific heat. • Alloys may display difference in behavior even when small amounts of impurities are present on one element of the alloy.
Specific heat capacity and heat capacity • Temperature of an object is a measure of its random molecular motions. • Temperature increases as the average speed of the atoms or molecules increases. • Different materials have different specific heat capacity because different types of molecules and atoms need different amounts of energy to raise their speed.
Specific heat capacity and heat capacity • For the similar material, a larger object will have a larger heat capacity • More molecules that must move faster to increase the temperature. • Therefore they need more thermal energy to raise the temperature.
Specific Heat Capacity and Heat exchanger If the fluid passing through the pipes is to be warmed: • Fluid to be warmed: low SHC • Fluid used to warm: low SHC • Pipes (fluid to be warmed passes through): low SHC
References: • http://www.lifetime-reliability.com/Training/TGT001%20Heat%20exchanger%20basics.pdf • http://hyperphysics.phy-astr.gsu.edu/HBASE/thermo/spht.html#c2 • http://www.economicexpert.com/a/Joule:per:kilogram:kelvin.htm • http://dic.academic.ru/dic.nsf/enwiki/17444 • http://physics.suite101.com/article.cfm/specific_heat_capacity • http://www.absoluteastronomy.com/topics/Specific_heat_capacity • http://books.google.com.sg/books?id=SE-s6b6W3N4C&pg=PA195&lpg=PA195&dq=specific+heat+capacity+in+heat+exchanger&source=bl&ots=R5lnhqoqbh&sig=SW568rWgY3pLDaEpRY-VsDInh2Y&hl=en&ei=Q7oCSvfoNsyGkQXoorzOBA&sa=X&oi=book_result&ct=result&resnum=7