By T Murrali:
Since its first patent in 1861 by Nikolaus Otto, the thermodynamic cycle has been adopted in various forms in the development of the internal combustion(IC) engine. The cylinder with piston was the most successful design though the position of the cylinders and their sizes were altered to suit their specific applications. Thus there were the opposed piston engine, the radial cylinder engine, and the maximum produced — In-Line and the V- type engines. Each had its use.
The evolution process brought in the rotary engines – there is no cylinder but suction and compression is created by an eccentrically mounted rotary within a complex-shaped chamber. It followed the same thermodynamic cycle. It had many advantages like compactness, less moving parts, minimum vibration, and better power-to-weight ratio. But the disadvantages like complexity of sealing, greater emissions, and lower fuel economy, far outweighed them. Hence it has not been as successful as the reciprocating or the piston type engines. However work is still going on to improve the IC engine.
The emerging technologies for electric mobility and stricter legislation on emissions propel the research on IC engines with greater resolve and urgency. The use of electronics and other technologies like turbo chargers, superchargers, variable valve timing etc. have made the engines more efficient.
Similar is the case with transmission systems that take power to the wheels. The basic principles of gear drive and using of differentials have remained the same. But they have been honed with precision engineering and electronics to sense and alter their performance for overall efficiency.
Of late, development of powertrains keeps environment as the key determinant along with enhancing efficiency. Electric vehicles constitute only less than one percent of the total production of passenger vehicles. However, they are set to grow exponentially with the technologies being developed on several fronts including batteries, motors, and controllers and wiring. While the Plug-in Hybrid Electric Vehicles and Electric Vehicles are being looked at as alternatives, there is also a growing interest in Fuel Cell technology.
According to ResearchAndMarkets, between 2013, when sales of EVs began, and 2017, a total of 6,364 hydrogen fuel cell vehicles have been sold globally. Over 50 percent of these vehicles were sold in California making the state a model of success in the deployment of the technology. Of the remaining countries, the lion’s share went to Japan which is at the forefront of hydrogen station deployments.
Among automakers, Toyota has been the most successful, accounting for over 77 percent of the sales. Hydrogen fuel cell vehicle sales in 2017 were almost double the total sales in the previous years. The EVs are specially designed to accommodate electric powertrain. But the fuel cell technologies are for adaptability. Modern fuel cell engine, as developed by Daimler, matches the conventional diesel powertrain in weight, profile, external dimensions and mounting points.