Thermal Engineering Questions and Answers – Dual Combustion Cycles

This set of Thermal Engineering written test Questions & Answers focuses on “Dual Combustion Cycles”.

1. What is the other name of dual cycle?
a) Mixed cycle
b) Otto cycle
c) Diesel cycle
d) Joule Cycle
View Answer

2. Dual cycle is combination of__________
a) Stirling and diesel cycle
b) Otto and diesel cycle
c) Stirling and otto cycle
d) Otto and Brayton cycle
View Answer

3. What is the efficiency of dual cycle?
a) 1-\(\frac{(ρ^γ r_p-1)}{(r_p-1)+γr_p (ρ-1)} \)
b) 1-\(\frac{1}{r^{γ-1}}\frac{(ρ^γ r_p-1)}{(r_p-1)+γr_p} \)
c) 1-\(\frac{1}{r^γ}\frac{(ρ^γ r_p-1)}{(r_p-1)+γr_p (ρ-1)} \)
d) 1-\(\frac{1}{r^{γ-1}}\frac{(ρ^γ r_p-1)}{(r_p-1)+γr_p (ρ-1)} \)
View Answer

4. Dual cycle consist of __________
a) Two constant pressure and two adiabatic process
b) Two constant volume and two adiabatic process
c) One constant pressure process, two constant volume process and two adiabatic process
d) One constant pressure process, one constant volume process and two adiabatic process
View Answer

5. In a dual cycle heat rejection takes place ______
a) At constant volume process
b) At constant pressure process
c) First at constant volume then at constant pressure process
d) First at constant pressure then at constant volume process
View Answer

6. In a dual cycle heat addition takes place ________
a) At constant volume process
b) At constant pressure process
c) First at constant volume then at constant pressure process
d) First at constant pressure then at constant volume process
View Answer

7. Most high speed compression ignition operates on ________
a) Diesel cycle
b) Otto cycle
c) Brayton cycle
d) Dual cycle
View Answer

8. What is the efficiency of dual cycle if compression ratio and cut-off ratio is equal to 15 and 1.4 respectively?
a) 91%
b) 90.8%
c) 90.6%
d) 90%
View Answer

9. What is the value of working fluid in dual cycle?
a) 1.0
b) 1.2
c) 1.4
d) 1.8
View Answer

10. The compression ratio (r) of dual cycle is equal to ________
a) r = volume of the cylinder at the beginning of the compression/volume of the cylinder at the end of the compression
b) r = volume of the cylinder at the end of the compression/ volume of the cylinder at the beginning of the compression
c) r = clearance volume/ volume of the cylinder at the beginning of the compression
d) r = volume of the cylinder at the end of the compression/clearance volume
View Answer

11. The cut-off ratio (ρ) of dual cycle is equal to ________
a) Volume at which fuel supply cutoff to volume at which fuel supply start
b) Volume at which fuel supply throughout the process to volume at which fuel supply cutoff
c) Volume at which fuel supply cutoff to volume of fuel supply throughout the process
d) Volume at which fuel supply start to volume at which fuel supply cutoff
View Answer

12. What is the efficiency of dual cycle if compression ratio and cut-off ratio is equal to 13 and 1.4 respectively?
a) 68%
b) 63%
c) 60%
d) 65%
View Answer

13. What is the relation between compression ratio, cutoff ratio and expansion ratio?
a) r_e = ρ×r
b) r_e = ρ/r
c) r_e = 1/ρr
d) r_e = r/ρ
View Answer

14. Determine the value of expansion ratio if compression ratio and cutoff ratio is equal to 15 and 1.4 respectively.
a) 10.5
b) 21
c) 11
d) 10.7
View Answer

15. Determine the value of cutoff ratio if compression ratio and expansion ratio is equal to 15 and 11 respectively.
a) 1.4
b) 1.36
c) 1.5
d) 1.3
View Answer

Sanfoundry Global Education & Learning Series – Thermal Engineering

To practice all written questions on Thermal Engineering, here is complete set of 1000+ Multiple Choice Questions and Answers.

If you find a mistake in question / option / answer, kindly take a screenshot and email to [email protected]