Fundamentals
Mechanics
IC Engines
Gyroscope
Vibration
Distance and Displacement
Starting from origin, O a person walks 90-m east, then turns
around and walks 40-m west.
Q: What is the total walked distance?
Distance and Displacement
Starting from origin, O a person walks 90-m east, then turns
around and walks 40-m west.
Q: What is the total walked distance? A: 130-m
Distance and Displacement
Starting from origin, O a person walks 90-m east, then turns
around and walks 40-m west.
Q: What is the total walked distance? A: 130-m
Q: What is the displacement?
Distance and Displacement
Starting from origin, O a person walks 90-m east, then turns
around and walks 40-m west.
Q: What is the total walked distance? A: 130-m
Q: What is the displacement? A: 50-m, due east.
Displacement


x  final position
xo  initial position
  
x  x  xo  displaceme nt
The displacement Δx is a vector that points from the initial position
to the final position. SI Unit of Displacement: meter (m)
2.2 Speed and Velocity
•Average Speed
•Average Velocity
•Instantaneous Velocity
•Instantaneous Speed
Average Speed
Units for speed: m/s, MPH, kmPH.
Average Velocity
Average velocity 
Displaceme nt
Elapsed time
 

 x  x o x
v

t  to
t
Units for velocity: m/s, MPH, kmPH.
Instantaneous Velocity and Speed
The instantaneous velocity v indicates how fast an object
moves and the direction of the motion at each instant of time.


x
v  lim
t  0 t
The magnitude of the instantaneous velocity is called the
instantaneous speed, and it is the number (with units) indicated
by the speedometer.
Acceleration
Acceleration
Units: m/s2, cm/s2
Instantaneous acceleration
Acceleration at a particular instant is called instantaneous
acceleration.
Pressure Vs Velocity
Statics
Kinematics
Kinetics
Internal Combustion Engines
Steady
Gas Turbine
Uses compressor and turbine,
not piston-cylinder
Non-steady
Premixed-charge
Fuel and air are mixed before/during compression
Usually ignited with spark after compression
Turboshaft
All shaft work to drive propeller,
generator, rotor (helicopter)
Two-stroke
One complete thermodynamic cycle
per revolution of engine
Turbofan
Part shaft, part jet "ducted propeller"
Four-stroke
One complete thermodynamic cycle
per two revolutions of engine
Turbojet
All jet except for work needed to
drive compressor
Ramjet
No compressor or turbine
Use high Mach no. ram effect for compression
Rocket
Carries both fuel and oxidant
Jet power only, no shaft work
Solid fuel
Fuel and oxidant are premixed
and put inside combustion chamber
Liquid fuel
Fuel and oxidant are initially separated
and pumped into combustion chamber
Non-premixed charge
Only air is compressed,
fuel is injected into cylinder after compression
Two-stroke
One complete thermodynamic cycle
per revolution of engine
Four-stroke
One complete thermodynamic cycle
per two revolutions of engine
Steady
non-steady
Turbo shaft
Turbo prop
Turbo jet
Ram jet
Rocket