HT Chapter 2 Flashcards
What is Conduction
Conduction is the transport of energy in a medium due to temperature gradient and by the random atomic or molecular activity.
Isothermal
same temperature
adiabatic
the temperature of a surface which cannot absorb or lose heat to the environment
Isotropic
the properties of a material which is independent of the direction
L
Thickness
Lambda mfp
Electron mean free path, average distance traveled by an electron before it collides with either an imperfection in the material or with a phonon.
specific heat
the amount of heat that must be added to one unit of mass of the substance in order to cause an increase of one unit in temperature.
thermal diffusivity
ratio of thermal conductivity to heat capacity
meaning of incompressible
constant density
cp
Specific heat at constant pressure
cv
specific heat at constant volume
q dot
rate at which energy is generated per unit volume (W/m^3)
watt units
j/s
alpha- meaning, formula, definition
thermal diffusivity, k/cp*row,thermal conductivity divided by density and specific heat capacity at constant pressure.
What does heat equation allow?
Heat equation allows us to calculate distribution of temperature vs time and x y and z
Thermal Conductivity
A measure of a materials ability to transfer thermal energy by conduction, symbol is K, and units is W/m^2
Thermal Diffusivity definition.
A measure of a material’s ability to respond to changes in its thermal environment.
What are the two components of thermal conductivity of metallic solids?
thermal conductivity of electrons and thermal conductivity of the lattice
What are the two components of thermal conductivity of non metallic solids?
thermal conductivity of the lattice
Why is thermal conductivity of pure metals higher then that of allows?
because pure metals have more free electrons
