Just back from a few days at the beach, here is just a quick one…
User BoH created a Sankey diagram for a diesel engine and uplodad it to the WikiCommons. It is in Dutch and shows the energy efficiency of the fuel being burnt in the motor.
49.3% of the energy is useful energy transformed into motion, while the rest is lost. The main losses (30.45%) occur at the exhaust gases, and with cooling water (approx 10.5%).
The smaller arrows are not to scale (see the 0.76% arrow branching off on the left side compared to the one representing 1.5% (smeeroliekoeling, cooling of lubricant oil)). Also, I am not sure whether the author forgot an arrow at the blue node labeled “Lucht” (air).
Anyway, apart from these flaws it is a neat diagram. I particularly like the color gradient from ‘red hot’ to ‘cool green’.