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The Diesel Engine at 120

It seemed a no-brainer invention, but it took quite some time to become the world’s leading source of locomotive power

3 min read
opening illustration for Numbers Don't Lie column
Illustration: Stuart Bradford

On 17 February 1897, Moritz Schröter, a professor of theoretical engineering at Technische Universität, in Munich, conducted the official certification test of Rudolf Diesel’s new engine. The goal of the test was to verify the machine’s efficiency and hence to demonstrate its suitability for commercial development.

The 4.5-metric-ton engine performed impressively: At its full power of 13.4 kilowatts (18 horsepower) the engine’s thermal efficiency was 35 percent and its mechanical efficiency reached 75 percent, resulting in a net efficiency of 26 percent. With obvious pride Diesel wrote to his wife, “Nobody’s engine design has achieved what mine has done, and so I can have the proud awareness of being the first one in my specialty.” Later in that year the engine’s net efficiency reached 30 percent, making the machine twice as efficient as the gasoline-fueled Otto engines of the day.

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How Software Is Eating the Car

The trend toward self-driving and electric vehicles will add hundreds of millions of lines of code to cars. Can the auto industry cope?

14 min read
ZF Friedrichshafen AG

Predictions of lost global vehicle production caused by the ongoing semiconductor shortage continue to rise. In January, analysts forecast that 1.5 million fewer vehicles would be produced as a result of the shortage; by April that number had steadily climbed to more than 2.7 million units, and by May, to more than 4.1 million units.

The semiconductor shortage has underscored not only the fragility of the automotive supply chain, but placed an intense spotlight on the auto industry’s reliance on the dozens of concealed computers embedded throughout vehicles today.

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