Aerospace Engineering Gate 2016 Questions with Answer

Ques 14 GATE 2016

A single-stage gas turbine operates with an axial absolute flow at the entry and exit from the stage. The absolute flow angle at the nozzle exit is 70°. The turbine stage generates a specific work of 228 kJ/kg when operating with a mean blade speed of 440 m/s. The absolute velocity at the rotor entry is

Ques 15 GATE 2016

An axial compressor operates such that it has an inlet and an exit total temperature of 300 K and 430 K, respectively. The isentropic efficiency of the compressor is 85%. If the ratio of specific heats is 1.4, then the total pressure ratio across the compressor is

Ques 16 GATE 2016

A gaseous mixture of air and fuel enters a constant area combustion chamber at a velocity of 100 m/s and at a static temperature of 300 K. The heat release due to combustion is 1000 kJ/kg. The specific heat at constant pressure of the calorically perfect gas is 1000 J/kgK. The total temperature of air-fuel mixture after combustion is _______ K.

Ques 17 GATE 2016

A wall of thickness 5 mm is heated by a hot gas flowing along the wall. The gas is at a temperature of 3000 K, and the convective heat transfer coefficient is 160 W/m²K. The wall thermal conductivity is 40 W/mK. If the colder side of the wall is held at 500 K, the temperature of the side exposed to the hot gas is _______ K.

Ques 18 GATE 2016

A launch vehicle has a main rocket engine with two identical strap-on motors, all of which fire simultaneously during the operation. The main engine delivers a thrust of 6300 kN with a specific impulse of 428 s. Each strap-on motor delivers a thrust of 12000 kN with specific impulse of 292 s. The acceleration due to gravity is 9.81 m/s² The effective (combined) specific impulse of the vehicle is _______ S.

Ques 19 GATE 2016

A substance experiences an entropy change of Δs>0 in a quasi-steady process. The rise in temperature (corresponding to the entropy change Δs) is highest for the following process:

Ques 20 GATE 2016

In a particular rocket engine, helium propellant is heated to 6000 K and 95% of its total enthalpy is recovered as kinetic energy of the nozzle exhaust. Consider helium to be a calorically perfect gas with specific heat at constant pressure of 5200 J/kgK. The exhaust velocity for such a rocket for an optimum expansion is _______ m/s.

Ques 21 GATE 2016

A rocket, with a total lift-off mass of 10000 kg, moves vertically upward from rest under a constant gravitational acceleration of 9.81 m/s² The propellant mass of 8400 kg burns at a constant rate of 1200 kg/s. If the specific impulse of the rocket engine is 240 s, neglecting drag, the burnout velocity in m/s is

Ques 22 GATE 2016

Which of the following aircraft engines has the highest propulsive efficiency at a cruising Mach number of less than 0.5?

Ques 23 GATE 2016

Combustion in gas turbine engines is ideally represented as the following process:

Ques 24 GATE 2016

For a given chamber pressure, the thrust of a rocket engine is highest when

Ques 25 GATE 2016

A bar made of linear elastic isotropic material is fixed at one end and subjected to an axial force of 1 kN at the other end. The cross-sectional area of the bar is 100 mm², length is 100 mm and the Young's Modulus is 1×10⁵N/mm². The strain energy stored in the bar is _______ Nmm.

Ques 26 GATE 2016

A cantilever beam-spring system is shown in the figure. The beam is made with a material of Young's modulus 1×10⁵N/mm² and geometry such that its moment of inertia is 100 mm⁴ and length I=100 mm. It is supported by a spring of stiffness K=30 N/mm and subjected to a load of P=100N at the point 'B'. The deflection at the point 'B' due to the load P is _______ mm.