List of top Mechanical Engineering Questions on Thermodynamics asked in TS PGECET

In a CI engine, the delay period in the combustion process mainly corresponds to
A balloon containing an ideal gas is initially kept in an evacuated and insulated room. If the balloon ruptures and the gas fills the entire room, what is the correct statement at the end of the process?
The maximum amount of low grade energy, which is convertible into work is known as
The whirl component of turbine blades is zero for the following turbine.
A single stage impulse turbine with a diameter of 1.2 m runs at 3000 rpm. If the blade speed ratio is 0.42, the inlet velocity of steam will be (in $\text{ms}^{-1}$)
In an ideal Brayton power cycle operated for the gas turbine plant, if \(T_1\) is the minimum temperature, \(T_3\) is the maximum temperature and pressure ratio is \(r_p\), then the net work ratio is given as
If regenerator is added to a Brayton cycle, the thermal efficiency is improved due to
Generally, in spark ignition engines, the compression ratio cannot be enhanced beyond certain limit because to avoid
The refrigerant and absorbent used in Vapour absorption refrigeration system respectively are
An air conditioning system mixes 30% fresh air at 35 $^\circ$C DBT and 50% RH with 70% recirculated air at 35 $^\circ$C DBT and 50% RH. Which of the following statements about "mixed air condition" is true?
If a substance is perfect crystal and existing at absolute zero K, then the specific entropy of the substance is
Based on second law of thermodynamics the loss in available energy is being quantified as
The clearance is provided in the reciprocating compressor with clearance ratio of `k'. If the pressure ratio is \(\frac{P_2}{P_1}\), then the volumetric efficiency in terms of clearance ratio k, is
In an axial flow compressor, if the air stream is not able to follow the blade contour such phenomena is known as
In a combined cycle for power generation, if the topping cycle has an efficiency of 45% and for bottoming cycle 30%, then the combined efficiency of the cycle is
A real gas undergoes throttling from 50 bar to 10 bar from an initial temperature of 300 K. If \(\mu_{JT} = -0.05 \text{ K/bar}\) for the initial condition, what is the approximate value of the exit temperature?
A mixture of gas expands from \(0.03 \text{ m}^3\) to \(0.06 \text{ m}^3\) at a constant pressure of 1 MPa and absorbs 84 kJ of heat during the process. The change in internal energy of the mixture is
Two reversible heat engines are operated with same heat input and heat output. One of the engine is operated between the temperature limits of \(T_2\) and 200 K & another is between 800 K and \(T_2\). Then the value of \(T_2\) is