1. Introductions

2. Design Considerations
Conservation of mass
It has got to go somewhere
Conservation of energy
Energy is transferred
Forms of energy and energy transfer LATER
How much is energy is where?

3. Conservation of Mass/Energy
In – out + generation – consumption = accumulation
Energy/mass can’t be generated or consumed
First law of thermodynamics

4. How much energy does something have?
Can we measure energy?
What CAN we measure?
Pressure
Temperature
Mass
Volume
So what?

5. State Postulate
If you know two INDEPENDENT, intensive properties of a system, you can know the complete state of the system
State – all of a system’s intensive properties

6. Intensive v. Extensive Extensive property Intensive property
Size dependent
“extent of system”
Intensive property
Size independent
Specific properties
Extensive properties normalized by mass/moles
Extensive / extensive = intensive

7. Intensive v. Extensive (Examples?)
Extensive property
Intensive property
Specific properties

8. Temperature It is NOT heat It is NOT energy
It is RELATED to energy
Kinetic energy = ½mv2 = 3/2 k*T
It is a measure of molecular velocity
Hotter  faster
Colder  slower
CW?

9. Pressure Tensor property (learn more in CBE 218)
Exertion of force on a boundary
How hard are the molecules hitting a boundary
Related to velocity through momentum (mv)

10. Others Volume – amount of space available to molecules
Mass – amount of matter
Moles – “count” of atoms/molecules
Density – mass in a set volume
Energy/similar – discuss later

11. Equilibrium Thermal – temperatures are the same
Zeroth law of thermodynamics:
“Body A is in thermal equilibrium with body B and body B is in thermal equilibrium with body C, body A and body C are in thermal equilibrium”
Mechanical – pressures are the same
Chemical – topic for CBE 321 but has to do with phases

12. Phase Equilibrium All equilibrium is satisfied Phases
Temperature and pressure are not independent
Phases
Solid
Liquid
Vapor
“gradual” transitions

13. P-T Phase Diagram P T

14. P-T Diagram

15. Triple/Critical Point
Liquid and vapor indistinguishable
Triple point
All three phases exist

16. P-v Phase Diagram
FIRST let’s do a
Concept Warehouse Question P v

17. P-v Phase Diagram

18. Saturation Saturated liquid Subcooled liquid Saturated vapor
All liquid, but with one bubble of vapor
Vapor has minute number of molecules
Subcooled liquid
Saturated vapor
Similar but opposite
Superheated vapor
Quality
“percent” of vapor in saturated mixture

19. Property Tables For common fluids (i.e. water)
If only we had a code to read the table for us

20. Concepts/Practice/Relevance
Concept warehouse
Track progress of pathways
Cooling of a gas in a rigid tank
Isobarically increase volume
Calculate quality of saturated mixture
Calculate specific volume