STEAM TURBINES (2 MARKS)

Steam enters an impulse turbine at a velocity of 500 m/s and having nozzle angle 20 deg. The symmetrical blades have a mean peripheral velocity of 300 m/s. Consider a mass flow rate of 0.75 kg/s. Find the blade angle in degree, assuming the steam enters the blade without shock.

• 15.1

• 45.2

• 25.5

• 10.4

Steam enters an impulse turbine at a velocity of 500 m/s and having nozzle angle 20 deg. The symmetrical blades have a mean peripheral velocity of 300 m/s. Consider a mass flow rate of 0.75 kg/s. Calculate the tangential forces on the blades (N) for the turbine . Neglect friction effects on blades.

• 546.36

• 498.65

• 660.54

• 254.77

Steam enters an impulse turbine at a velocity of 500 m/s and having nozzle angle 20 deg. The symmetrical blades have a mean peripheral velocity of 300 m/s. Consider a mass flow rate of 0.75 kg/s. Estimate the axial thrust (N), assuming the steam enters the blade without shock.

• 0

• 0.01

• 0.15

• 1.52

Steam enters an impulse turbine at a velocity of 500 m/s and having nozzle angle 20 deg. The symmetrical blades have a mean peripheral velocity of 300 m/s. Consider a mass flow rate of 0.75 kg/s. Estimate the diagram efficiency (in %), assuming the steam enters the blade without shock.

• 79.65

• 81.52

• 80.65

• 91.65

Steam enters an impulse turbine at a velocity of 500 m/s and having nozzle angle 20 deg. The symmetrical blades have a mean peripheral velocity of 300 m/s. Consider a mass flow rate of 0.75 kg/s. Estimate the axial thrust (N), if the relative velocity is reduced to 80% of that at inlet due to friction

• 49.65

• 41.36

• 25.65

• 50.65

Steam enters an impulse turbine at a velocity of 500 m/s and having nozzle angle 20 deg. The symmetrical blades have a mean peripheral velocity of 300 m/s. Consider a mass flow rate of 0.75 kg/s. Estimate the diagram power (kW) , if the relative velocity is reduced to 80% of that at inlet due to friction

• 148.56

• 179.36

• 200.36

• 68.77

Steam enters an impulse turbine at a velocity of 500 m/s and having nozzle angle 20 deg. The symmetrical blades have a mean peripheral velocity of 300 m/s. Consider a mass flow rate of 0.75 kg/s. Estimate the diagram efficiency (in %), if the relative velocity is reduced to 80% of that at inlet due to friction

• 73.35

• 70.65

• 78.55

• 79.36

A 50% reaction turbine is rotating at 2400 rpm with a mean blade speed of 100 m/s. The exit angle of blades is 20 deg. and the velocity ratio is 0.56. The mean specific volume of steam is 0.65 cub.m/kg and the mean height of blade is 25 mm. Neglect effect of blade thickness on the annulus area. Calculate the mass flow of steam through the turbine in kg/h.

• 29340

• 21147

• 25365

• 30285

A 50% reaction turbine is rotating at 2400 rpm with a mean blade speed of 100 m/s. The exit angle of blades is 20 deg. and the velocity ratio is 0.56. The mean specific volume of steam is 0.65 cub.m/kg and the mean height of blade is 25 mm. Neglect effect of blade thickness on the annulus area. calculate the diagram power (kW) if there are five pair of blades in the group.

• 429.7

• 235.8

• 565.3

• 691.4

A 50% reaction turbine is rotating at 2400 rpm with a mean blade speed of 100 m/s. The exit angle of blades is 20 deg. and the velocity ratio is 0.56. The mean specific volume of steam is 0.65 cub.m/kg and the mean height of blade is 25 mm. Neglect effect of blade thickness on the annulus area. Calculate the useful enthalpy drop (kJ/kg) if there are five pair of blades in the group.

• 117.8

• 170.2

• 161.3

• 198.9