Detailed study report on "Performance and emission analysis on oxygen enriched variable Oxygen Enriched variable compression ratio Diesel Engine". This paper is related to Automobile,Mechanical and Thermal Engineering. Enriched oxygen was supplied to the combustion chamber of a Diesel engine in varied load and varied combustion ratio and optimum combustion ratio was noted. Result is reduction in specific fuel consumption, increment in break thermal efficiency, carbon dioxide emission considerably reduced.

1. Performance and Emission Analysis on
Oxygen Enriched variable
compression ratio Diesel Engine
SREESANKAR J
M.E THERMAL ENGG
SNS COLLEGE OF
TECHNOLOGY
COIMBATORE-35

2. Abstract
• In this work, the investigation is carried out in variable
compression ratio diesel engine with air side oxygen
enrichment.
• This investigation aims to find out the optimum level of
performance with various flow rates of oxygen and for
various compression ratios.
• Initially the base line engine performance and emission
characteristics are determined at different loads with
different flow rates of oxygen.

3. Abstract
The experimental investigation shows that :
• Increase brake thermal efficiency of the engine
• brake specific fuel consumption and total fuel
consumption decreases
• The emission result indicates that there is a
significant amount of reduction in CO emissions with
the increase in flow rate of oxygen.

4. INTRODUCTION
• Diesel engines have considerable advantages in the market in
the form of its power output, fuel economy and durability.
• environmental concerns and the emission regulations, said
that to reduce emission of diesel engine simultaneously while
keeping up a good fuel economy and power output.
• The IC engine is to produce mechanical power from chemical
energy which is contained in the fuel.
• In recent years, growing concerns about environmental
preservation have created a demand for a lower pollution
automotive diesel engine.

5. LITERATURE REVIEW
• Watson, et al conducted experiments with oxygen-enriched
air (up to 30% O2 by volume). They achieved about 80%
reduction in smoke at full load and 5% to 12% increase of
thermal efficiency and also a decrease of CO and HC
emissions. However, NOx emission increased due to the
increase of oxygen concentration and cycle temperatures.
• Poola, et al conducted experiments with oxygen enriched air
in SI engine to reduce HC and CO emissions. It had a great
advantage in the period where the catalytic converter
temperature was below light off level. They achieved about
60% to 70% reduction in HC and CO emission levels with an
increase of 23% of oxygen by volume.

6. EXPERIMENTAL SETUP
• An oxygen cylinder is connected to the inlet manifold
of the diesel engine.
• oxygen flow meter is connected at the beginning of
the connection from the oxygen cylinder.
• A mixing chamber is fixed to the inlet manifold of the
engine for effective mixing of oxygen and air.

7. Engine configurations

8. Experimental Setup

9. Oxygen flow meter

10. Mixing Chamber

11. Experimental Setup
• Initially the experiment is conducted on a baseline engine
which means without making any hardware modifications on
the engine and the performance and emission characteristics
are measured.
• The oxygen flow meter is used for setting up the various flow
rates of oxygen in litres per minute.
• The flow rate of the oxygen is varied from 1 litre per minute
to 7 litres per minute.

12. Experimental Setup
• For each flow rate of the oxygen the load is varied from no
load to 8 kg and at each load condition, the performance and
emission characteristics of the engine is examined and the
results are compared with the performance and emission
characteristics of the baseline engine which is not connected
with the oxygen cylinder.
• The same procedure is applied to five different compression
ratios which vary from 14:1 to 18:1 and the performance and
emission characteristics are examined with oxygen being
injected into the inlet manifold of the engine through a
mixing chamber at various flow rates.

13. Measuring Methods
• brake thermal efficiency and fuel
consumptions are calculated by measuring the
fuel inlet flow rate to the engine which is
measured using a burette along with scale.
• the exhaust emissions are measured with the
help of exhaust gas analyzer (Kane-May 900
Combustion Analyzer and smoke meter.

14. RESULTS AND DISCUSSION
• The brake thermal efficiency of the engine
was found to have a gradual increase with
increase in oxygen flow rate.

15. Load vs brake thermal efficiency
(C.R.14:1)

16. Load vs brake thermal efficiency
(C.R.15:1)

17. Load vs brake thermal efficiency
(C.R.16:1)

18. Load vs brake thermal efficiency
(C.R.17:1)

19. Load vs brake thermal efficiency
(C.R.18:1)

20. RESULTS AND DISCUSSION
• The maximum brake thermal efficiency was
experienced at flow rate of 7 liters/minute at
the Compression ratio of 17:1

21. RESULTS AND DISCUSSION
• The specific fuel consumption decreases with
increase in the flow rate of oxygen.

22. Load vs Specific fuel consumption
(C.R.14:1)

23. Load vs Specific fuel consumption
(C.R.15:1)

24. Load vs Specific fuel consumption
(C.R.16:1)

25. Load vs Specific fuel consumption
(C.R.17:1)

26. Load vs Specific fuel consumption
(C.R.18:1)

27. RESULTS AND DISCUSSION
• The lowest specific fuel consumption was
experienced at an oxygen flow rate of 7
liters/minute and at a compression ratio of
18:1.

28. RESULTS AND DISCUSSION
• The emission analysis shows that with the
increase in oxygen flow rate there was a
significant reduction in CO emissions.

29. Load vs CO (C.R.14:1)

30. Load vs CO (C.R.15:1)

31. Load vs CO (C.R.16:1)

32. Load vs CO (C.R.17:1)

33. Load vs CO (C.R.18:1)

34. CONCLUSION
• The brake thermal efficiency is increased with
increase in load and oxygen flow rate and the
maximum of which was experienced at oxygen flow
rate of 7 liters/minute and at the Compression ratio
of 17:1.
• The specific fuel consumption was gradually reduced
with increase in load and oxygen flow rate and it was
lowest at the oxygen flow rate 7 litres per minute.

35. CONCLUSION
• The CO emissions were found to be reduced
gradually with increase in oxygen flow rate and it
was lowest at the oxygen flow rate of 7 liters per
minute.
• The NOx emissions were found to be increasing
gradually with increase in load and oxygen flow rate
and which is due to increased combustion
temperatures and oxygen concentration.

36. CONCLUSION
• The performance and emission characteristics
of the engine were found to be optimum at
the Compression ratio of 16:1.
• So, the engine can be operated efficiently by
setting the compression ratio to 16:1.

37. REFERENCES
1. G A Karim and G Ward., ”The Examination of the Combustion Process in a Compression
Ignition Engine by Changing the Partial Pressure of Oxygen in the Intake Charge,” SAE
Paper No 680767.
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900344.
3. R B Poola, et al., ”Utilizing Intake Air Oxygen-enrichment Technology to Reduce Cold-phase
Emissions,” SAE Paper No 952420.
4. R J Donahue and D E Foster., ”Effect of Oxygen Enhancement on the Emission from DI
Diesel via Manipulation of Fuel and Combustion Chamber Gas Composition,” SAE Paper No
2001-01-0512.
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Paper No 659-666.
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doi:10.4271/901565.

38. REFERENCES
7. Marr, W., Sekar, R., Cole, R., Marciniak, T. et al., "Oxygen-Enriched Diesel Engine
Experiments with a Low-Grade Fuel," SAE Technical Paper 932805, 1993,
doi:10.4271/932805.
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