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On a p-v-t-surface, the triple point and the critical point are seen respectively as

Line, line

Line, point

Point, line

Point, point

Which of the following coal variety has the highest calorific value

Anthracite

Bituminous

Lignite

Peat

The fuel mostly used in boilers is

Anthracite

Peat

Lignite

Bituminous

Consider the following statements de laval nozzle is a subsonic nozzle supersonic nozzle is a converging passage subsonic diffusion is a diverging passage Which of these statements is/are correct?

1 and 2

2 and 3

1 alone

3 alone

Neglecting approach velocity, the theoretical velocity at nozzle exit equals

C=91.5

C=44.7

C=68.6

None of the above

Under ideal conditions, the velocity of steam at the outlet of a nozzle for a heat drop of 400 kJ/kg will be approximately

1200 m/s

900 m/s

600 m/s

The same as sonic speed

The cross-section of a nozzle is Circular Elliptical Square Rectangular Which of these statements is/are correct?

1 and 2

2 and 3

1 and 3

1, 2 and 3

Choose the incorrect statement in the context of flow through a nozzle

Velocity increases at almost constant rate throughout the entire nozzle length

Specific volume of steam increases very rapidly during later part of expansion

Area decreases when specific volume increases less rapidly than increase in velocity

The ratio (velocity/specific volume) has minimum value at the nozzle throat

The critical pressure ratio for maximum discharge through a nozzle is given by

=

=

=

=

Where n is the value of exponent for the adiabatic expansion process.

For steam having inintial dryness fraction x, the value of exponent n for the adiabatic expansion through a nozzle can be worked out by using the Zeuner’s equation prescribed as

n=1.035+0.1x

n=1.35+0.1x

n=1.3+0.15x

n=1.15+0.1x

Which relation is valid for flow of superheated flow through a nozzle?

pv1.135=c

pv1.13=c

pv1.035=c

pv1.55=c

The value of critical pressure ratio for dry saturated steam is

0.525

0.546

0.578

0.627

Critical pressure ratio for superheated steam is

0.525

0.546

0.578

0.615

In a de-laval nozzle expanding super heated steam from 10bar to 0.1bar, the pressure at the minimum cross-section will be

3.3bar

5.46bar

5.78bar

8.2bar

Efficiency of chimney draught is of the order of

8-10%

5-6%

2-3%

Less than 1%

Line, line

Line, point

Point, line

Point, point

Which of the following coal variety has the highest calorific value

Anthracite

Bituminous

Lignite

Peat

The fuel mostly used in boilers is

Anthracite

Peat

Lignite

Bituminous

Consider the following statements de laval nozzle is a subsonic nozzle supersonic nozzle is a converging passage subsonic diffusion is a diverging passage Which of these statements is/are correct?

1 and 2

2 and 3

1 alone

3 alone

Neglecting approach velocity, the theoretical velocity at nozzle exit equals

C=91.5

C=44.7

C=68.6

None of the above

Under ideal conditions, the velocity of steam at the outlet of a nozzle for a heat drop of 400 kJ/kg will be approximately

1200 m/s

900 m/s

600 m/s

The same as sonic speed

The cross-section of a nozzle is Circular Elliptical Square Rectangular Which of these statements is/are correct?

1 and 2

2 and 3

1 and 3

1, 2 and 3

Choose the incorrect statement in the context of flow through a nozzle

Velocity increases at almost constant rate throughout the entire nozzle length

Specific volume of steam increases very rapidly during later part of expansion

Area decreases when specific volume increases less rapidly than increase in velocity

The ratio (velocity/specific volume) has minimum value at the nozzle throat

The critical pressure ratio for maximum discharge through a nozzle is given by

=

=

=

=

Where n is the value of exponent for the adiabatic expansion process.

For steam having inintial dryness fraction x, the value of exponent n for the adiabatic expansion through a nozzle can be worked out by using the Zeuner’s equation prescribed as

n=1.035+0.1x

n=1.35+0.1x

n=1.3+0.15x

n=1.15+0.1x

Which relation is valid for flow of superheated flow through a nozzle?

pv1.135=c

pv1.13=c

pv1.035=c

pv1.55=c

The value of critical pressure ratio for dry saturated steam is

0.525

0.546

0.578

0.627

Critical pressure ratio for superheated steam is

0.525

0.546

0.578

0.615

In a de-laval nozzle expanding super heated steam from 10bar to 0.1bar, the pressure at the minimum cross-section will be

3.3bar

5.46bar

5.78bar

8.2bar

Efficiency of chimney draught is of the order of

8-10%

5-6%

2-3%

Less than 1%

This is a 15-question test on ‘Steam: Generation, Engines and Turbines’ under a series of tests of Mechanical Engineering which is attributed to Competitive Examination Preparations e.g. IAS (Optional), GATE, IES etc.

anthracite has the highest calorific value 36000kj/kg

whereas bituminious coal has 35000kj/kg...kindly change the answer.anthracite is the final stage of coal formation after bituminious coal

4058 days 5 hours 36 minutes ago

excellent question. and need more... asked in different competitve exams ,it will help as practice to score beteer in final exam.

4090 days 13 hours 7 minutes ago

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