Criteria S.I. Engine (Petrol or Spark Ignition Engine) C.I. Engine (Diesel or Compression Ignition Engine) Working Cycle Works on Otto Cycle or Constant Volume Cycle. Works on Diesel Cycle. Mixture During Suction Stroke Takes a mixture of air and petrol during the suction stroke. Takes only air during the suction stroke. Fuel Used Uses petrol as fuel. Uses diesel as fuel. Compression Ratio Has a compression ratio that varies from 6 to 10. Has a compression ratio that varies from 16 to 20. Engine Weight and Cost S.I. engines are lighter and cheaper. C.I. engines are heavier and costlier. Initial Cost Initial cost is lower compared to C.I. engines. Initial cost is high due to high compression ratio. Starting Starting is easy. Starting is difficult, especially in cold conditions. ...
Thermodynamics -
Thermo means heat, dynamic means motion.
Thermodynamics is the field of science which deals with the study about relation between heat , work and energy and their conversation into each other.
#) IMPORTANT thermodynamics definitions:-
1.) System - it is defined as the quantity of matter in a space upon which attention is focused for study.
2.) Surroundings - Everything is external to the system is called surroundings.
3.) Boundary - it is kind of envelope which separates the system from surroundings.
4.) Universe - A system and it's surrounding together form a universe.
5.) State - The condition of a system at any instant of time described by its physical properties is known as State.
#.) TYPES OF THERMODYNAMICS SYSTEM:-
a.) Closed system
b.) Open system
c.) Isolated system
a.) Closed system - when no mass transfer across the system boundry.
examples:-
1.Piston cylinder arrangements containing gas
2.) If we boil the water in closed container then no mass is transferred but heat is transferred surroundings environment.
b.) Open system - when there is mass and energy pass through across the system boundry.
examples:-
1. Air compressor
2. If we boil the water in an open container like a pot without cover then water convert in steam and transferred to the surrounding environment with heat. So that means mass and heat is both is transferred across the system.
c.) Isolated system:- there is no transfer of mass and energy to and from the system.
example:- Thermal bottle
#) Homogeneous and Heterogeneous system:-
Pahse - A quantity of Matter that is uniform throughout in chemical composition.
Phase of water ( solid, liquid, vapour)
Solid ( ice)
Liquid ( water )
Vapour ( steam )
Homogeneous system - it is a system which consists only single phase.
example:- (gas+ air+ nitrogen) all gases are different but having same phase.
HETEROGENEOUS SYSTEM - it consists of more than one phase.
Example:- ( water + vapour+ ice) all phases are different like solid , liquid, gas.
THERMODYNAMICS PROPERTY - Are 2
1.) Intensive or intrinsic property - The properties which do not depend upon mass of system.
example:- Temp, pressure, Density and viscosity.
2.) Extensive or Extrinsic property - The property which do not depend upon mass.
EXAMPLE:- • Energy
• HEAT
• ENTROPY
• ENTHALPY
THERMODYNAMICS EQUILIBRIUM:- The
Word equilibrium is originate by two word Equal + Libra.
a.) Mechanical equilibrium:- in the absence of any unbalanced force within the system and also between the system and surrounding.
Simply when two forces are equal
F1 = F2
b.) Thermal equilibrium:- when the temp of system is uniform.
T1 = T2
c.) chemical equilibrium:- when there is no chemical reaction whitin the system or between the system.
L.H.S = R.H.S