🌘
Week 5 Warmte & Gasdynamica
Thermische processen
H19 Heat and the first Law of Thermodynamics
The first law of thermodynamics
Heat is defined as a transfer of energy due to a difference in temperature, whereas work is a transfer
of energy that is not due to a temperature difference. Work is done when energy is transferred from 1
object to another by mechanical means.
FIRST LAW OF THERMODYNAMICS : the change in internal energy of a closed system , dEint, will be
equal to the energy added to the system by heating minus the work done by the system in the
surroundings (gesloten systeem)
Bij open systemen alle toe en afnemen van massa meenemen!
Quantities which describe the state of a system, such as internal energy Eint, pressure P, volume V,
temperature T and mass m or number of moles n, are called state variables.
Een system met kinetische energie K (0.5*m*v^2), potentiële energie U (mgh) geeft voor de 1e
hoofdwet :
Week 5 Warmte & Gasdynamica 1
, The first law of thermodynamics applied; Calculating the Work
Er zijn 4 verschillende soorten processen
Isotherm dT = 0, geen verandering in temperatuur. If the system is an ideal gas, then PV = nRT.
The work done by the gas in an isothermal process equals the heat added to the gas.
Adiabatisch Q = 0, geen warmte uitwisseling met omgeving. The internal energy decreases if the
gas expansds, the temperature decreases as well. dEint = -W
Isobaar dP = 0, geen verandering in druk
Isovolumetrisch dV= 0, geen verandering in volume
Een verandering van de verrichte arbeid is afhankelijk van de volume verandering.
De verrichte arbeid is dan ook gelijk aan het oppervlak onder het PV - diagram.
Week 5 Warmte & Gasdynamica 2
Week 5 Warmte & Gasdynamica
Thermische processen
H19 Heat and the first Law of Thermodynamics
The first law of thermodynamics
Heat is defined as a transfer of energy due to a difference in temperature, whereas work is a transfer
of energy that is not due to a temperature difference. Work is done when energy is transferred from 1
object to another by mechanical means.
FIRST LAW OF THERMODYNAMICS : the change in internal energy of a closed system , dEint, will be
equal to the energy added to the system by heating minus the work done by the system in the
surroundings (gesloten systeem)
Bij open systemen alle toe en afnemen van massa meenemen!
Quantities which describe the state of a system, such as internal energy Eint, pressure P, volume V,
temperature T and mass m or number of moles n, are called state variables.
Een system met kinetische energie K (0.5*m*v^2), potentiële energie U (mgh) geeft voor de 1e
hoofdwet :
Week 5 Warmte & Gasdynamica 1
, The first law of thermodynamics applied; Calculating the Work
Er zijn 4 verschillende soorten processen
Isotherm dT = 0, geen verandering in temperatuur. If the system is an ideal gas, then PV = nRT.
The work done by the gas in an isothermal process equals the heat added to the gas.
Adiabatisch Q = 0, geen warmte uitwisseling met omgeving. The internal energy decreases if the
gas expansds, the temperature decreases as well. dEint = -W
Isobaar dP = 0, geen verandering in druk
Isovolumetrisch dV= 0, geen verandering in volume
Een verandering van de verrichte arbeid is afhankelijk van de volume verandering.
De verrichte arbeid is dan ook gelijk aan het oppervlak onder het PV - diagram.
Week 5 Warmte & Gasdynamica 2