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click here 👉 for or other PPTs like unit1 which covers Lecture 1, Lacture2, Lacture3 and Lecture 4 similarly unit 2 covers ideal Gas and Second law of thermodynamics unit3 covers Entropy and availability unit4 covers properties of pure substance , thermodynamics of vapour cycle unit 5 covers Fuel and combustion and unit 6 steam generator and boiler draft.
FUNDAMENTALS OF THERMODYNAMICS
ZEROTH LAW OF THERMODYNAMICS
By replacing the Third Body with a Thermometer; the Zeroth Law can be stated as :
Two bodies are in Thermal Equilibrium, if both have same TEMPERATURE, regarding even if they are not in contact with each other.
This statement seems to be very simple.
However, this can not be directly concluded from the other Laws of Thermodynamics.
It serves as the basis of validity of TEMPERATURE measurement.
Definition: It comprises study of molecular behavior of system and it is predicted by statistical approach.
Example : Temperature measurement, pressure measurement, total volume measurement, specific volume measurement. Thus, microscopic point of view will be used only to explain some phenomena that can’t be understood by macroscopic means.
Application: The macroscopic analysis is used in study of engineering applications like compressors, heat engines, turbines, pumps etc.
MICROSCOPIC AROACH TO THERMODYNAMICS
It is an approach in which the thermodynamic system is analyzed with deeper understanding of molecular level of the system and looking at the individual behavior of the molecules.
Application:
The microscopic analysis is used in kinetic theory of gases, system having high vacuum etc.
THERMODYNAMIC PROPERTIES:
Measurable Characteristics of system which would describe or identify the system.
Eg. Mass, Volume, Temperature, Pressure, Surface area, Density, Velocity, Enthalpy, Entropy
Intensive properties
Extensive properties
INTENSIVE PROPERTIES:
Independent of the mass
Examples: pressure, temperature,
EXTENSIVE PROPERTIES:
Depends on the size or extent of system
There is an increase in the value of extensive property whenever there is an increase in mass.
Example: Mass, Volume, Total Energy
The state may be identified or described by certain observable macroscopic properties; some familiar one are temperature, pressure and density.
The state is specified or described by the properties. The state point can be indicated on a thermodynamic coordinate system.
Assume a System NOT undergoing any change.
Set of properties to completely describe the condition of the system is known as its STATE
POINT AND PATH FUNCTIONS
Point functions are those for which the change depends on only the end states and not on the path followed
Point functions are exact differentials
dP = P2 - P1
dV = V2 - V1
Path functions are those for which the change depends not only on the end states but also on the path followed
Path functions are inexact differentials
dW ≠ W2 - W1
dQ ≠ Q2 - Q1
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