If the clearance ratio for a reciprocating air compressor is 'K', then its volumetric efficiency is given by

A $$1 - {\text{K}} + {\text{K}}{\left( {\frac{{{{\text{p}}_1}}}{{{{\text{p}}_2}}}} \right)^{\frac{1}{{\text{n}}}}}$$
B $$1 + {\text{K}} - {\text{K}}{\left( {\frac{{{{\text{p}}_2}}}{{{{\text{p}}_1}}}} \right)^{\frac{1}{{\text{n}}}}}$$
C $$1 - {\text{K}} + {\text{K}}{\left( {\frac{{{{\text{p}}_1}}}{{{{\text{p}}_2}}}} \right)^{\frac{{{\text{n}} - 1}}{{\text{n}}}}}$$
D $$1 + {\text{K}} - {\text{K}}{\left( {\frac{{{{\text{p}}_2}}}{{{{\text{p}}_1}}}} \right)^{\frac{{{\text{n}} - 1}}{{\text{n}}}}}$$

Correct Answer: $$1 + {\text{K}} - {\text{K}}{\left( {\frac{{{{\text{p}}_2}}}{{{{\text{p}}_1}}}} \right)^{\frac{1}{{\text{n}}}}}$$

If the clearance ratio for a reciprocating air compressor is 'K', then its volumetric efficiency is given by $$1 + {\text{K}} - {\text{K}}{\left( {\frac{{{{\text{p}}_2}}}{{{{\text{p}}_1}}}} \right)^{\frac{1}{{\text{n}}}}}$$
Bissoy MCQ
#Mechanical Engineering #Compressors #Gas Turbines And Jet Engines

Related Questions

In a single acting reciprocating air compressor, without clearance, the compression of air may be
A Isothermal
B Polytropic
C Isentropic
D Any one of these
Volumetric efficiency of a compressor without clearance volume
A Increases with increase in compression ratio
B Decreases with increase in compression ratio
C Is not dependent upon compression ratio
D May increase/decrease depending on compressor capacity
Volumetric efficiency of a compressor with clearance volume
A Increases with increase in compression ratio
B Decreases with increase in compression ratio
C In not dependent upon compression ratio
D May increase/decrease depending on compressor capacity
In a single stage, single acting reciprocating air compressor without clearance volume, the work-done is maximum during
A Isothermal compression
B Isentropic compression
C Polytropic compression
D None of these
In a single stage, single acting reciprocating air compressor, without clearance volume, the work-done is minimum during
A Isothermal compression
B Isentropic compression
C Polytropic compression
D None of these
The primary unbalanced force due to inertia of reciprocating parts in a reciprocating engine is given by (where m = Mass of reciprocating parts, $$\omega $$ = Angular speed of crank, r = Radius of crank, $$\theta $$ = Angle of inclination of crank with the line of stroke and n = Ratio of the length of connecting rod to radius of crank)
A $${\text{m}}{\omega ^2}{\text{r}}\sin \theta $$
B $${\text{m}}{\omega ^2}{\text{r}}\cos \theta $$
C $${\text{m}}{\omega ^2}{\text{r}}\frac{{\sin 2\theta }}{{\text{n}}}$$
D $${\text{m}}{\omega ^2}{\text{r}}\frac{{\cos2\theta }}{{\text{n}}}$$
The secondary unbalanced force due to inertia of reciprocating parts in a reciprocating engine is given by (where m = Mass of reciprocating parts, $$\omega $$ = Angular speed of crank, r = Radius of crank, $$\theta $$ = Angle of inclination of crank with the line of stroke and n = Ratio of the length of connecting rod to radius of crank)
A $${\text{m}}{\omega ^2}{\text{r}}\sin \theta $$
B $${\text{m}}{\omega ^2}{\text{r}}\cos \theta $$
C $${\text{m}}{\omega ^2}{\text{r}}\frac{{\sin 2\theta }}{{\text{n}}}$$
D $${\text{m}}{\omega ^2}{\text{r}}\frac{{\cos2\theta }}{{\text{n}}}$$
The variable required to be known in correlations used for estimating the horse power of a centrifugal gas compressor and hence its cost are P. Inlet pressure Q. Compressor rpm R. Delivery pressure S. Volumetric flow rate at inlet.
A P, Q and R
B P and R
C R and S
D P, R and S
With increase in compression ratio, the volumetric efficiency of air compressor
A Increases
B Decreases
C Remains same
D May increase or decrease (depends on the suction pressure)
A large clearance volume in a reciprocating compressor results in
A Reduced volume flow rate
B Increased volume flow rate
C Lower suction pressure
D Lower delivery pressure

Next steps