This document contains the complete B.Tech Semester III – Theory Examination 2017–18 question paper for Thermodynamics (RME-302). The paper spans three pages, carries 70 marks, and evaluates a student’s understanding of fundamental laws of thermodynamics, energy transfer, entropy, steady-flow devices, heat engines, refrigeration cycles, and real-gas behavior.
Section A – Short Conceptual Questions (14 Marks)
Section A includes seven 2-mark questions that test essential thermodynamic definitions and principles:
Meaning and discussion of a quasi-static process
Carnot theorem and ideal heat engine limitations
Concept of entropy
Definition of second-law efficiency
Joule–Thomson coefficient and its significance
Triple point and critical point of a substance
Definition of refrigeration effect
These questions ensure a strong foundation in classical thermodynamics.
Section B – Numerical & Analytical Problems (21 Marks)
Students must attempt any three out of five detailed questions involving derivations and numerical calculations:
Derivation of the Steady Flow Energy Equation (SFEE) and its application to heat exchangers, nozzles, turbines, pumps & boilers
A complex p–v process involving internal energy calculation, quasi-static work, heat transfer, and comparison between reversible and irreversible work
Two reversible heat engines in series → determining intermediate temperature, efficiencies, and heat rejection
Entropy change during cooling/heating of an iron cube dropped in water, and determining whether the process is reversible or irreversible
Coefficient of volume expansion, adiabatic & isothermal compressibility, and loss in available energy for gas receiving heat from a high-temperature reservoir
These questions test the student's depth in applying first-law and second-law concepts to real engineering systems.
Section C – Long, Advanced Thermodynamics Questions (35 Marks)
Each question contains two advanced subparts, and the student must attempt one from each group.
Q3 – Nozzles / Polytropic Processes
Exit velocity & mass flow rate of a nozzle using enthalpy drop
Area change based on specific volume variation
OR
Polytropic expansion in a flexible container with given internal-energy drop → compute work and heat transfer
Q4 – Mixing / Thermodynamic Laws
Adiabatic mixing of hot & cold water → entropy change
OR
Limitations of First Law, statements of Second Law, and proof that violating Kelvin–Planck statement violates the Clausius statement
Q5 – Availability / Real-Gas Equations
Maximum useful work available from a heat reservoir and loss in availability due to temperature drop
OR
Clapeyron equation, Joule–Kelvin effect, inversion curve & inversion temperature
Q6 – Rankine Cycle / Steady Flow Turbine
Full explanation of the Rankine cycle with P-V and T-S diagrams & calculation of changes in thermodynamic properties when water is heated to superheated steam
OR
Power output of a steam turbine using SFEE with elevation, enthalpy, velocity, and heat-loss data
Q7 – Refrigeration Cycles
Vapor Compression Refrigeration (VCR) cycle, T-S & P-H diagrams, flow diagram, COP & reversibility
OR
Bell–Coleman (Air Refrigeration) cycle → finding COP using polytropic relations
This section thoroughly examines higher-level thermodynamic reasoning and engineering application.
Summary
This Thermodynamics (RME-302) exam paper thoroughly evaluates:
First & Second Laws of Thermodynamics
Carnot cycle & ideal heat engines
Entropy & availability (exergy)
SFEE & steady-flow devices (turbines, nozzles, pumps, compressors)
Real gas behavior (Joule–Thomson effect, inversion temperature)
Heat engines & refrigeration cycles (VCR, Bell-Coleman)
Rankine cycle & steam power plant basics
Entropy generation & irreversibility
It is a complete academic resource for mechanical engineering students studying classical & applied thermodynamics.
