D

B3D087S Pages: 2

Reg. No. Name:

APJ ABDUL KALAM TECHNOLOGICAL UNIVERSITY
THIRD SEMESTER B.TECH DEGREE EXAMINATION, JULY 2017

ME205: THERMODYNAMICS (AN, MA, MP, ME)

Max. Marks: 100 Duration: 3 Hours

PARTA
Answer any THREE questions.

. a) Define thermometric property. Why is a gas chosen as standard thermometric

substance (3)

b) Explain temperature scale. How can the ideal gas temperature for the steam point
be measured? (4) c) Show

that work is a path function and not a property (3)

. a) State first law for closed system undergoing a change of state and show that energy

a property of system (3)

b) Define enthalpy. Why the enthalpy of an ideal gas does depend only on
temperature? (3)

c) A gas of 4 kg is contained within the piston cylinder machine. The gas undergoes a
process for which ‏۷۱۵م‎ = Constant. The initial pressure is 3 bar and the initial
volume 15 0.107, and the final volume is 0.2൩. The specific internal energy of the
gas decreases by 4.6kJ/kg. There is no significant change in KE and PE. Determine
net

heat transfer for the process. (4)

. a) Define specific heat and derive it for constant pressure and constant volume?

(4)

b) A turbo compressor delivers 2.33 മ്‌ /ട at 0.276 MPa, 43°C which is heated at this
pressure to 430°C and finally expanded in a turbine which delivers 1860 kW. During
the expansion, there is a heat transfer of 0.09 MJ/s to the surroundings. Calculate
the turbine exhaust temperature if changes in kinetic and potential energy are
negligible?

(6)

. a) Write steady flow energy equation for a single stream entering and single stream

leaving a control volume and explain the various terms init. (4)

b) A pump steadily delivers water at a volumetric flow rate of 0.05m*/s through a pipe
of diameter 18 cm located 100 m above the inlet pipe which has a diameter of 15
cm. The pressure is nearly equal to 1 bar at both the inlet and the exit, and the
temperature is nearly constant at 20°C throughout. Determine the power required by
the pump.

Take 85 9.81 m/s” (6)

PART ந
Answer any THREE questions.

. a) Establish the equivalence of Kelvin-Plank and Clausius statements. (4)

b) A heat pump working on the Carnot cycle takes in heat from a reservoir at 5°C and
delivers heat to a reservoir at 60°C. The heat pump is driven by a reversible heat engine
which takes in heat from a reservoir at 840°C and rejects heat to a reservoir at 60°C.
The reversible heat engine also drives a machine that absorbs 30kW. If the heat