Producer gas is produced by
Carbonisation of coal
Passing steam over incandescent coke
Passing air and a large amount of steam over waste coal at about 65°C
Partial combustion of coal, coke, anthracite coal or charcoal in a mixed air steam blast
Correct Answer :
D. Partial combustion of coal, coke, anthracite coal or charcoal in a mixed air steam blast
Related Questions
Propulsive efficiency is defined as ratio of
Thrust power and fuel energy
Engine output and propulsive power
Propulsive power and fuel input
Thrust power and propulsive power
Actual compression curve is
Same as isothermal
Same as adiabatic
Better than isothermal and adiabatic
In between isothermal and adiabatic
Free air is the air at
Atmospheric conditions at any specific location
20°C and 1 kg/cm² and relative humidity of 36%
0°C and standard atmospheric conditions
15°C and 1 kg/cm²
The velocity of air entering in a rocket is ________ as compared to an aircraft.
Zero
Less
More
Same
Separators are generally used in air compressor installations
Before the intercooler
After the intercooler
Between the aftercooler and receiver
Before first stage suction
The ratio of the volume of free air delivery per stroke to the swept volume of the piston, is known as
Compressor efficiency
Volumetric efficiency
Isothermal efficiency
Mechanical efficiency
The criterion of the thermodynamic efficiency for rotary compressor is
Isentropic compression
Isothermal compression
Polytropic compression
None of the above
A closed gas turbine in which fuel is burnt directly in the air is not possible because of
Paucity of O2
Increasing gas temperature
High specific volume
High friction losses
In a single stage, single acting reciprocating air compressor, without clearance volume, the workdone is minimum during
Isothermal compression
Isentropic compression
Polytropic compression
None of these
Pick up the false statement
Gas turbine is a self starting unit
Gas turbine does not require huge quantity of water like steam plant
Exhaust losses in gas turbine are high due to large mass flow rate
Overall efficiency of gas turbine plant is lower than that of a reciprocating engine
The specific output per kg mass flow rate of a gas turbine (having fixed efficiencies of compressor and turbine and fixed higher and lower temperature) with increase in pressure ratio will
Increase first at fast rate and then slow
Increase first at slow rate and then fast
Decrease continuously
First increase, reach maximum and then decrease
A large clearance volume in a reciprocating compressor results in
Reduced volume flow rate
Increased volume flow rate
Lower suction pressure
Lower delivery pressure
Aeroplanes employ following type of compressor
Radial flow
Axial flow
Centrifugal
None of the above
What will be the volume of air at 327°C if its volume at 27°C is 1.5 m³/ mt?
3 m³/ mt.
1.5 m³/ mt.
18 m³/ mt.
6 m³/ mt.
If p₁, is the pressure of air entering the L.P. cylinder and p₂ is the pressure of air leaving the L.P. cylinder (or intercooler pressure), then the ratio of cylinder diameters for a single acting, two stage reciprocating air compressor with complete intercooling is given by (where D₁ = Dia. of L.P. cylinder, and D₂ = Dia. of H.P. cylinder)
D₁/D₂ = p₁ p₂
D₁/D₂ = p₁/p₂
D₁/D₂ = p₂/p₁
None of these
A gas turbine used in air craft should have
High h.p. and low weight
Low weight and small frontal area
Small frontal area and high h.p.
High speed and high h.p
The volumetric efficiency for reciprocating air compressors is about
10 to 40 %
40 to 60 %
60 to 70 %
70 to 90 %
The thermodynamic efficiency of rotary compressor is based on
Isothermal compression
Adiabatic compression
Isentropic compression
Polytropic compression
The efficiency of a jet engine is higher at
Low speeds
High speeds
Low altitudes
High altitudes
A jet engine has
No propeller
Propeller in front
Propeller at back
Propeller on the top
The volume of air sucked by the compressor during its suction stroke is called
Free air delivery
Compressor capacity
Swept volume
None of these
More than one stage will be preferred for reciprocating compressor if the delivery pressure is more than
2 kg/cm²
6 kg/cm²
10 kg/cm²
14.7 kg/cm²
An air compressor may be controlled by
Throttle control
Clearance control
Blow off control
Any one of the above
Producer gas is produced by
Carbonisation of coal
Passing steam over incandescent coke
Passing air and a large amount of steam over waste coal at about 65°C
Partial combustion of coal, coke, anthracite coal or charcoal in a mixed air steam blast
Which of the following statement is correct?
The reciprocating compressors are best suited for high pressure and low volume capacity
The effect of clearance volume on power consumption is negligible for the same volume of discharge
Both (A) and (B)
None of these
The efficiency of jet engine is
Lower at low speed
Higher at high altitudes
Same at all altitudes
Higher at high speed
In air compressors, free air delivery means the
Actual volume of the air delivered by the compressor when reduced to normal temperature and pressure conditions
Volume of air delivered by the compressor
Volume of air sucked by the compressor during its suction stroke
None of the above
Open cycle gas turbine works on
Brayton or Atkinson cycle
Rankine cycle
Carnot cycle
Erricson cycle
For perfect intercooling in a two stage compressor
p₂/p₁ = p₃/p₂
p₁/p₃ = p₂/p₁
p₁ = p₃
p₁ = p₂ p₃
In a centrifugal compressor, the highest Mach number leading to shock wave in the fluid flow occurs at
Diffuser inlet radius
Diffuser outlet radius
Impeller inlet radius
Impeller outlet radius