This is a great video if you love learning about engines. Gong back to the time of WWII, it takes us through the basic design and operation of a few different types of diesel engines that were used on submarines at the time. There’s the “traditional” four stroke, the two stroke, the double acting piston engine, the opposed piston engine, and more. This is all done in a clear, concise, and really interesting way. The animations are great and they make sense of some stuff that we had been confused about, especially when it comes to the opposed and double acting stuff.
There’ so many interesting ways people have tried to make the piston engine better, stronger, and more efficient over the years. While many of them have failed by and large, engineers have learned something from every blind hole they ever jumped down.
No, we are not driving cars around with opposed or double acting piston engines, but the design was the right layout for stuff of this size and scale back in the day. Imagine being a kid off the farm and out of basic training, now learning about what your job as a mechanic would be and this is the first thing you see.