To avoid moisture troubles, the compressed air main line should
Rise gradually towards the point of use
Drop gradually towards the point of use
Be laid vertically
Be laid exactly horizontally
Correct Answer :
B. Drop gradually towards the point of use
Related Questions
A jet engine works on the principle of conservation of
Mass
Energy
Flow
Linear momentum
An aftercooler is used to
Remove impurities from air
Reduce volume of air
Cause moisture and oil vapour to drop out
Cool the air
High air-fuel ratio is used in gas turbines
To increase the output
To increase the efficiency
To save fuel
To reduce the exit temperature
When the outlet angle from the rotor of a centrifugal compressor is more than 90°, then the blades are said to be
Forward curved
Backward curved
Radial
None of these
The volume of air sucked by the compressor during its suction stroke is called
Free air delivery
Compressor capacity
Swept volume
None of these
In a single stage, single acting reciprocating air compressor without clearance volume, the workdone is maximum during
Isothermal compression
Isentropic compression
Polytropic compression
None of these
A closed cycle gas turbine gives ________ efficiency as compared to an open cycle gas turbine.
Same
Lower
Higher
None of these
Euler's equation can be used for
Radial flow compressors
Axial flow compressors
Pumps
All of these
The type of rotary compressor used in aeroplanes, is of
Centrifugal type
Axial flow type
Radial flow type
None of these
For an irreversible gas turbine cycle, the efficiency and work ratio both depend on
Pressure ratio alone
Maximum cycle temperature alone
Minimum cycle temperature alone
Both pressure ratio and maximum cycle temperature
For a two stage reciprocating compressor, compression from p₁ to p₃ is with perfect intercooling and no pressure losses. If compression in both the cylinders follows the same polytropic process and the atmospheric pressure is pa, then the intermediate pressure p₂ is given by
p₂ = (p₁ + p₃)/2
p₂ = p₁. p₃
P₂ = Pa × p₃/p₁
p₂ = Pa p₃/p₁
In a centrifugal compressor, the flow of air is ________ to the axis of compressor.
Parallel
Perpendicular
Inclined
None of these
The work ratio of simple gas turbine cycle depends on
Pressure ratio
Maximum cycle temperature
Minimum cycle temperature
All of the above
Axial flow compressor resembles
Centrifugal pump
Reciprocating pump
Turbine
Sliding vane compressor
In a closed cycle gas turbine, the air is compressed
Isothermally
Polytropically
Isentropically
None of these
If the flow of air through the compressor is parallel to its axis, then the compressor is
Reciprocating compressor
Centrifugal compressor
Axial flow compressor
Turbo compressor
In the axial flow gas turbine, the work ratio is the ratio of
Compressor work and turbine work
Output and input
Actual total head temperature drop to the isentropic total head drop from total head inlet to static head outlet
Actual compressor work and theoretical compressor work
A 3 m³/min compressor means that it
Compresses 3 m³/min of standard air
Compresses 3 m³/ min of free air
Delivers 3 m³/ min of compressed air
Delivers 3 m³/ min of compressed air at delivery pressure
The efficiency of a jet engine is higher at
Low speeds
High speeds
Low altitudes
High altitudes
The closed cycle in gas turbines
Provides greater flexibility
Provides lesser flexibility
In never used
Is used when gas is to be burnt
A rocket engine uses ________ for the combustion of its fuel.
Surrounding air
Compressed atmospheric air
Its own oxygen
None of these
The overall isothermal efficiency of compressor is defined as the ratio of
Isothermal h.p. to the BHP of motor
Isothermal h.p. to adiabatic h.p.
Power to drive compressor to isothermal h.p.
Work to compress air isothermally to work for actual compression
The absolute pressure of air at the outlet of a compressor is called
Back pressure
Critical pressure
Discharge pressure
None of these
The advantage of multistage compression over single stage compression is
Lower power consumption per unit of air delivered
Higher volumetric efficiency
Decreased discharge temperature
All of the above
The ratio of specific weight/h.p. of gas turbine and I.C engines may be typically of the order of
1 : 1
2 : 1
4 : 1
1 : 6
Ram compression in turbojet involves
Reduction of speed of incoming air and conversion of part of it into pressure energy
Compression of inlet air
Increasing speed of incoming air
Lost work
The process, which causes the air to enter the impeller blades of a centrifugal compressor at ________ velocity (without effecting the mass of air to flow and velocity of flow) is known as prewhirl.
Reduced
Increased
Zero
None of these
The air entry velocity m a rocket as compared to aircraft is
Same
More
Less
Zero
In a double acting compressor, the air is compressed
In one cylinder
In two cylinders
In a single cylinder on both sides of the piston
In two cylinders on both sides of the piston
The maximum delivery pressure in a rotary air compressor is
10 bar
20 bar
30 bar
50 bar