The, Fluid, CRE Flashcards
0th Law of Thermodynamics
(Proponent, Definition)
Ralph Howard Fowler
If TA=TB and TB=TC, then TA=TC
1st Law of Thermodynamics
(Proponent, Definition)
Rudolf Julius Emanuel Clausius
-Law of Conservation of Energy
-Energy can’t be created/destroyed, only transformed
-Energy of universe is constant
-The total energy of any system and its surroundings is conserved.
2nd Law of Thermo (Clausius Statement)
(Proponent, Definition)
A device that solely transfers heat from low to high temperature is impossible. Work is required.
2nd Law of Thermo (Kelvin-Planck Statement)
A) Impossible for device to completely convert heat to work (n < 1, and n < n,Carnot), effect to surroundings always exist.
B) Impossible for any device operating on a cycle to receive heat from a SINGLE RESERVOIR ONLY and produce a net amount of work. A hot and cold reservoir are required.
Device violating 1st Law of Thermo
PMM1 - Perpetual motion machine of first kind
Device violating 2nd Law of Thermo
PMM2 - Perpetual motion machine of second kind
How to calculate non reversible entropy?
Entropy is state function. S,rev = S,irrev
3rd Law of Thermodynamics
Walther Hermann Nernst
- S=0 at absolute zero (especially perfect crystals), then S>0 for everything else
Carnot Theorem
Nicolas Sadi Carnot
-n,Carnot = n,max (No engine is more efficient than Carnot engine)
- Any reversible engine between two heat reservoirs is a Carnot Engine
For Carnot engines:
Its efficiency depends only on _____ and not the working substance of the engine.
temperature levels (Tc and Th)
The equation, PV = nRT is best obeyed by gases at
low pressure and high temperature
Compressibility factor of a gas is
a. not a function of pressure
b. not a function of its nature
c. not a function of its temperature
d. unity, if it follows PV = nRT
d. unity, if it follows PV = nRT
Gibbs Free Energy
(Proponent, Equation, Definition)
Josiah Willard Gibbs
G=H-TS
Maximum work by system at P&T=k
Helmholtz Free Energy
(Proponent, Equation, Definition)
Hermann Ludwig Ferdinand von Helmholtz
A=U-TS
Maximum work by system at T=k
Otto Cycle
(Describe, by who, steps)
Ideal Spark Ignition Engine
Nikolaus August Otto
1-2: S=k, +W
2-3: V=k, QH <—- diff from Diesel
3-4: S=k, -W
4-1: V=k, QC
Diesel Cycle
(Describe, by who, steps)
Ideal Compression-Ignition Engine
Rudolf Christian Karl Diesel
1-2: S=k, +W
2-3: P=k, QH <—- diff from Otto
3-4: S=k, -W
4-1: V=k, QC
Rankine Cycle
(Describe, by who, steps)
Ideal Vapor Power Cycle
William John Macquorn Rankine
Steps: PaBaTaC
1-2: S=k, +W (PUMP)
2-3: P=k, QH (BOILER)
3-4: S=k, -W (TURBINE)
4-1: P=k, QC (CONDENSER) <— diff from Gas Power Cycles
A gas turbine cycle consisting of two adiabatic steps and two isobaric steps.
Brayton cycle
A device substantially without moving parts, in which a fuel, such as hydrogen, natural gas, methanol, propane, can be converted directly into twice the quantity of electrical energy that would result from the usual boiler-turbine-generator combination.
fuel cell
Describes the temperature change of a fluid when it is throttled
Joule-Thomson Effect
Explain Joule Thomson Effect
The Joule–Thomson effect is the change in temperature of a gas when it undergoes isenthalpic expansion.
Joule-Thomson experiment is ____
a. isobaric
b. adiabatic
c. isenthalpic
d. both(b) & (c)
d. Adiabatic and Isenthalpic
Process that can be reversed without leaving any trace on the surroundings
Reversible process
Temperature scales with ratios that depend on ratios of heat transfer between a reversible heat engine and the reservoirs.
Absolute temperature scales