DTS-i Triple Spark technology

Outline

1. Introduction

2. Working

3. Position of spark plugs

4. Tests conducted

5. Combustion comparison

7. Advantages and limitations

8. Conclusion

Reference

Introduction

What is “TRIPLE SPARK” technology?

Triple Spark technology uses three spark plugs to ignite the fuel as against single spark plug in the conventional petrol engine design.

How Triple Spark technology works?

This technology is developed by Bajaj Auto and is implemented in Bajaj Pulsar 200NS.

It consists of two inlet valves and two outlet valves and three Spark plugs.The two inlet valves allow the air fuel mixture to flow freely to the combustion chamber.

The two outlet valves allow the exhaust gases to be released smoothly.This helps the engine breathe easily even at high RPMs.

Packing in 4 valves and three spark plugs within the tight combustion chamber is no mean feat which indicates the engineering excellence of Bajaj R&D team.

working

The master plug takes the center place and the two slave plugs opposition across the lateral axis of the engine head. (Over square configuration).

This configuration helps in delaying the ignition timing almost by 15 degree TDC yet resulting in optimal combustion.

Position of spark plugs

Position of single spark plug

Apache RTR 180 with single spark ignition

Position of Twin Spark Plug

Pulsar 220 F with twin spark ignition

Position of Triple spark plug

Triple spark combustion Chamber

Pulsar 200NS with Triple Spark ignition

Tests conducted

Single vs. Twin vs. Triple Spark ignitions

Changes in brake specific fuel consumption with load for single plug, twin plug and triple plug modes. Following observation can be made from it:

BSFC is very high at the initial stage for all three engines.

It is maximum for single spark engine and minimum for the triple spark engine.

BRAKE SPECIFIC FUEL CONSUMPTION V/S LOAD

Changes in Volumetric Efficiency with load for single plug, twin plug and triple plug modes. Following observation can be made from it:

• Initially volumetric efficiency is maximum for single spark engine and minimum for triple spark engine.

• In all the cases it increases with the increase in the load.

VOLUMETRIC EFFICIENCY V/S LOAD

Changes in un burnt hydrocarbon with load for single plug, twin plug and triple plug modes. Following observation can be made from it:

• UBHC emissions are higher in single spark engine because of incomplete combustion.

• Triple spark engines have lesser and better UBHC emission due to better and faster completion of combustion.

UNBURNT HYDROCARBON EMMISION VS LOAD

Changes in CO emission with load for single plug, twin plug and triple plug modes. Following observation can be made from it:

• CO emissions are highest for the single spark engine due to incomplete combustion.

• It is least for the triple spark engine.

• CO emissions decrease with load in all three conditions because at high temperature CO gets oxidized.

CO EMISSION V/S LOAD

Changes in Nox emissions with load for single plug, twin plug and triple plug modes. Following observation can be made from it:

• NOx emissions are higher for twin and triple Plug engine at initial conditions.

• It increases with the load till 2.1kg in all three engines.

• Curve of triple plug engine tends to approach minimum value due to liquid cooling.

Nox EMISSION V/S LOAD

Combustion Comparison

Comparison b/w single, twin & triple spark ignition

As we can notice that in spite of 15 degree later ignition timing in the triple spark system the combustion ends in advance of the others.

What can be achieved from this

Resulting in more power and better fuel efficiency.

The ignition of the three spark plugs is controlled by Electronic Control Unit which is also called an ECU.

The ECU uses different ignition maps for different riding conditions to ensure that the flame propagation in the combustion chamber is optimal.

As for cruisingThe ECU responses calmly

And during top speed.The ECU response is faster than usual

This helps in achieving:

Bajaj Pulsar 200 AS

Which is a boon for a critical sports bike. This technology can be found in the following machines:

Bajaj Pulsar RS 200

Easier starting. Superior running with min vibrations and noise. Less emissions. More output power and thermal efficiency. Less prone to plug fouling. Smooth working even at higher RPMs. No issues on Cold air intake. No chances of knocking.

ADVANTAGES

Costlier Technology. Complications in its design. Fault in ECU can lead to malfunctioning of

engine. Requires high cooling (liquid cooled). Failure in cooling can cause severe damage to

engine. Heavier engine compared to twin spark and single

spark engines.

LIMITATIONS

Following conclusions are made according to experimental results:

Combustion process in triple spark engine takes place 27% faster than twin spark and 50% than single spark engine due to faster flame propagation.

Brake thermal efficiency of twin spark engine is 5.1% higher and BTE of triple spark engine is about 13% higher than single spark engine.

CONCLUSION

Narasimha bailkeri, Krishna Prasad and Shrinivasa Rao B.R ,(2013) Comparative study of Performance of Dual plug and single plug S.I engine at different compression ratios, International Journals Of Advanced Research In Engineering And Technology (IJARET), Volume 4, Issue 5, pp. 188-197.

Narasimha bailkeri, Krishna Prasad and Shrinivasa Rao B.R ,(2013) Performance Study on Twin Plug Spark Ignition Engine at Different Ignition Timings, International Journal of Science and Research (IJSR), Volume 2 Issue 8, India Online ISSN: 2319-7064.

Ajay K.Singh , A.Rehman,( 2013) The Effect of Dual Spark Plug on Engine Performance Parameter in Two Stroke Gasoline Engine, International Journal of Applied Research and Studies (iJARS) ISSN: 2278-9480 Volume 2, Issue 7.

Vi H. Rapp, Anthony DeFilippo, Samveg Saxena, Jyh-Yuan Chen,RobertW. Dibble,Atsushi Nishiyama, AhsaMoon, and Yuji Ikeda,(2012) Extending Lean Operating Limit and Reducing Emissions of Methane Spark-Ignited Engines Using a Microwave-Assisted Spark Plug, Hindawi Publishing Corporation, Journal of Combustion, Volume 2012, Article ID 927081, doi:10.1155/2012/927081.

REFERENCES

A video representing the triple spark ignition system and the machine in which it is implemented