h&f lecture 1&2

Question 1

what is heat transfer?

Answer 1

heat transfer is thermal energy in transit- as a result of temperature differences

Question 2

what is momentum transfer?

Answer 2

acceleration or deceleration of fluid particles as a result of motive or retardive forces

Question 3

what is mass transfer?

Answer 3

mass transfer is mass in transit as a result of concentration differences

Question 4

phase change example?

Answer 4

water evaporating, energy is taken from the water droplet (cooling) allowing it to break liquid bond, this energy turns into laten heat as the liquid turns into a gas, this energy is released as the gas is condensed back into a liquid

Question 5

is the model Eulerian or Lagrangian

Answer 5

model fixed in space = Eulerian

model allowd to flow with fluid = Lagrangian

Question 6

examples of 2D flow

Answer 6

Finite control volume fixed in space (eulerian) with fluid flowing through it OR Finite control volume moving with the fluid such that the same fluid particles are always in the same control volume

Question 7

examples of 3D Flow

Answer 7

Infinitesimal fluid element fixed in space with fluid flowing through it OR Infinitesimal fluid element flowing along the streamline with velocity equal to the local flow velocity at each point.

Question 8

delta phi = ?

Answer 8

Net convection + net diffusion + sources/sink + effects on cv surface (shear/normal stresses)

Question 9

what are the four physical fundamental principles?

Answer 9

mass, energy, species consentration and momentum