Third year, Department of Mechanical Sandwich
Engineering
First and second Units Questions.
Answer ALL questions
PART A – (10×2=20 marks)
1. Define Density
and Specific weight.
2. Define
atmospheric pressure and gauge pressure.
3. Classification
of thermodynamic system.
4. Define surrounding
?
5. Define cycle ?
6. Explain Zeroth
law of thermodynamics
7. Explain
First law of thermodynamics
8. When a system is
said to be in Thermodynamics Equilibrium.
9. Explain Free Expansion
process.
10. Define Kinetic
energy.
PART B – (5x16=80 marks)
11)
Derive an expression for the value of polytropic process.
12)
5 kg of air at 400C and 1 bar is heated in a reversible non-flow
constant pressure until the this volume is double. Find (1) change in volume
(2) work done (3) change in internal energy (4)change in enthalpy.
13)
0.25 Kg of a air pressure of 1 bar
occupy the volume of 0.3 m3.If
this a expand Ios thermally. To a volume of 0.9m3. Find the (i) The
initial temperature (ii) Final temperature
(iii) external work (iv) heat
observer by the air (v) change in internal energy. Assume R=0.29
KJ/Kg.K
14)
A gas of mass 0.35Kg pressure 1535 KN/m2 and temperature of 3350C
is expand adiabatically to a pressure of 126 KN/m2. The gas is then
heat at a constant volume. Until its reach 3350 c, when it pressure
isfound to be 275kn/m2, finaly the gas is compressed isothermally,
until the original pressure 1535kn/m2 obtained. Draw the p,v diagram and find out the following
(i)
The valve of adiabetic index
(ii)
Change in internal energy during adiabetic process
(iii)
Heat transfer , During constant valume process
Take cp=1.005KJ/Kg.k
15)
A steam turbine operates under steady flow condition. If received steam
7200Kg/hr from the boiler. The steam enter the turbine at enthalpy of 2800KJ/Kg
a velocity of 400m/min and an evalvation 4m. The steam leaves the turbine at
the enthalpy of 200KJ/Kg . A velocity of 8000m/min and an evalvation 1m. Due to
radiation the amount of heat loss from the turbine to the surrounding is
1500KJ/hr. Calculate the power output of the turbine.
0 Comments