Not only cars, motorcyclist now suffer the pain. Previously, with Modenas Kriss 110cc, one can fill up petrol full tank for only RM5. Now, they can merely got 2 litre with the current price of RM5.40 provided RM2.70 per litre. Pretty tough, eh? Especially for those low-income and mid-income earners who came to work by motorbike, plus factor living in Klang Valley.
But too bad, Modenas Kriss is a 4–stroke engine similar to Honda EX5. Research papers covers 2–stroke engine motorcycle like Yamaha RXZ, Yamaha 125z, Yamaha 135LC etc.
I came across Wata’s blog, the Malaysian Oil & Gas Engineer. There’s a success according to NGVGlobal about Two-Stroke Natural Gas Conversion Goes Large Scale with Yamaha RS100T motorcycle.
Read the research paper from our local university, Universiti Teknologi Malaysia (UTM) in their Universiti Teknologi Malaysia Institutional Repository.
Development of a compressed natural gas (CNG) mixer for a two stroke internal combustion engine
Ramasamy, Devarajan (2005) Development of a compressed natural gas (CNG) mixer for a two stroke internal combustion engine. Masters thesis, Universiti Teknologi Malaysia.
Compressed Natural Gas (CNG) has been accepted widely as an alternative to gasoline. More importantly the use of CNG in two stroke engines will drastically reduce the high emission output from these engines as these engines are widely used around the world. A conversion kit is used to apply the fuel in engines. A bi-fuel conversion system converts engines without much modification to other systems. They are normally produced for four stroke application. This kit has to be studied to be modified for two stroke application. The part that connects the engine to the kit is called a gaseous fuel mixer. This part mixes the air and fuel due to its venturi shape. A mixer provides fuel suction at different engine speeds due to pressure difference at the throat. The optimisation of the throat is important as a small throat will cause poor performance at high speeds while a large throat will reduce fuel suction. The smaller throat size creates higher velocity and lower pressure. This low pressure creates fuel suction into the mixer. The mixer was designed for a two stroke engine air flow. Computer aided design (CAD) and computational fluid dynamic (CFD) software were used as a tool for the design. The design is optimised for inlet and outlet angles, number and size of the hole at the throat circumference and also the throat size. The prototype design was manufactured based on optimised dimensions of the mixer that were obtained from CFD analysis. The mixer was validated to show that the CFD analysis was correct. Testing apparatus were used to do the validation. The apparatus consists of a laminar flow element (LFE), a smoke generator, a digital manometer and a gaseous flow meter. It was used to validate the flow pattern, pressure drop from the mixer and the air fuel ratio given by the mixer
Read also about Environment Canada, Canadian International Development Agency and it’s successfullness in converting 3–wheel rickshaw titled:
The Introduction of CNG as Alternative Fuel for Two-stroke Vehicles, Autorickshaw Demonstration Project in Pakistan
We have converted 60 rickshaws in Pakistan since November 2000 which are being monitored by the local EPA staff for technical and environmental performance. The owner-operators of these rickshaws were selected from a group of volunteers who had the option to have their CNG kits removed at no cost to them. Some did opt out because CNG refueling stations are still not as widely available as gasoline filling stations.
However, the kits were reinstalled in rickshaws which were on the short-list. Users have got the hang of the technology and initial fears of starting trouble, engine heat up and power loss have been overcome. As before, the rickshaws are by and large maintained by the owner-operators themselves. It is commonly assumed that CNG reduces a vehicle’s power.
Although this is a common observation in retrofitted cars also, it should not necessarily be the case. CNG is a more powerful fuel than gasoline. Its octane number is 130 compared with 87 for normal grade gasoline. We were surprised to learn that a local rickshaw owner, who had a family owned repair shop in Lahore, increased the compression ratio of his rickshaw to match the more powerful CNG. When we checked its compression power, it was more than five horsepower, slightly more than a brand new gasoline operated rickshaw!
So, will this benefitting Malaysian in future?
1 comment so far ↓
Dear Fren,
You are using my thesis as a reference?
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