THERMODYNAMICS
• Thermo = Heat, Dynamics = motion
∴ Thermodynamics means "heat in motion".
Thermodynamics is the branch of engineering science which answer the following question:
i) whether a process is feasible or not?
ii) to quantify the energy required for a process.
iii) extent to which a reaction/process takes place
Terminology:-
i) SYSTEM:- It is a prescribed region in space where our focus attention is to study their properties.
There are 3 type of system, i.e.
(a) open system
(b) closed system
(c) isolated system
(a) OPEN SYSTEM:- The system is said to be an open system if both mass and energy interaction takes place.
It is also called a control volume.
Example:- Pressure cooker without a valve, all flow (steady flow) system, centrifugal pump etc.
(b) CLOSED SYSTEM:- The system is said to be a closed system if only energy interaction takes place.
It is also called as control mass.
Example:- Pressure cooker with valve, a piston-cylinder arrangement without valve
(C) ISOLATED SYSTEM:- The system is said to be an isolated system if neither mass nor energy interaction takes place.
Example:- Universe,thermoflask(partially isolated system)
ii) BOUNDARY:- Everything external to the system is called boundary. The boundary can be fixed or movable.
Example:- In piston cylinder arrangement, the piston (boundary) is movable.