Lecture 4 macro Flashcards
1
Q
Conservation of mass principle
A
Rate of mass accumulation in the system = Rate of production of mass in the system + Net rate of mass entering the system
2
Q
Mass flowrate
A
w (kg/s)
Rate at which mass enters/exits a system
w = ρ* Qv = ρ*average v
3
Q
Volumetric flow
A
For uniform density over inlet/outlet:
Qv (m^3/s) = average velocity * x-sec Area
4
Q
What does well-mixed mean
A
When a fluid enters the system, the density becomes uniform instantly within the system
ρ sys = ρ out
5
Q
What does steady state flow mean for mass conservation
A
no mass accumulation
dm/dt = 0
6
Q
What does incompressible mean
A
Given fluid has constant density -> conservation of volume
Can be mixed fluid, therefore system fluid has varying density, but for pure fluid, no ρ change
