DTS Si technology

DTS Si: How Digital Twin Spark-Swirl induction System Works? Read This…

What is DTS Si?

DTS Si stands for 'Digital Twin Spark-Swirl induction' system. Some of Bajaj’s bike engines have its patented ‘DTS Si’ (Digital Twin Spark-Swirl induction) technology. Bajaj Auto claims that new engine with swirl induction gives better mileage under ideal (standard) test conditions which is higher than some of the 100cc motorcycles offer.

Bajaj Auto’s R&D designed and developed the DTS Si technology entirely in-house and claims it to be India’s most fuel-efficient motorcycle engine. The motorcycle engine which offers the best of both worlds that is the average of 100cc bike and the performance of 125cc bike.

What is Swirl induction?

The Digital Twin Spark–Swirl induction or DTS Si technology originates from the DTS-i platform. The DTS-i provides fast rate of combustion. Bajaj R&D found that when burning lean air-fuel mixtures, the two plugs provide rapid combustion. However, at light loads, there is further scope to improve the combustion quality.

Normally under these conditions, the quality and concentration of the air-fuel mixtures varies from one area to another within the combustion chamber. However, by generating high turbulence inside the combustion chamber the efficiency of combustion under lean air-fuel mixtures conditions further improves.

According to Bajaj R&D, the combustion chamber having low turbulence spreads the flame which is like a gradually expanding balloon. This results in a slower rate of combustion and raises the pressure slowly. Thus, it results in lower efficiency.

Conventional SI Engine with single spark plug
Conventional SI Engine with single spark plug

When the combustion takes place under high turbulence, the surface of the inflating flame fragments itself. It forms projections like fingers, increases the surface area and thereby, further improves the combustion.

Configuration of ports:

However, the conventional engines using straight ports have limitations in creating high swirl values due to their geometry. One of the ways of creating more turbulence or swirl is having a port configuration that stimulates this process. Bajaj engineers optimised the configuration by designing offset ports which create the required degree of swirl. The offset positioning of the ports generate relatively high swirl and turbulence of the air-fuel mixture in the combustion chamber.

DTS Si with Twin Spark plugs
DTS Si with Twin Spark plugs

This technology finds it way in the newer engine which creates swirling motion of the incoming charge. It creates turbulence as the piston moves in the Intake and Compression strokes. This results in thoroughly mixing of the air-fuel mixture and spreads it in the combustion chamber.

The twin spark plugs provide the sparks to ignite this turbulent and compressed air-fuel mixture. This leads to a flame front of high surface area which quickly raises the pressure because of fast combustion. Thus, DTS-i combined with Swirl induction provides extremely fast combustion which results in better efficiency.

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