Rankine scale, an absolute-temperature scale related to the Fahrenheit scale
where the actual temperature and critical temperature are expressed in absolute temperature scales (either Kelvin or Rankine).
Richter magnitude scale | scale | Moment magnitude scale | Fujita scale | Scale model | Rankine | scale model | Scale insect | Rostral scale | Dean Rankine | Scoville scale | Mercalli intensity scale | International Scale of River Difficulty | Beaufort scale | Synoptic scale meteorology | Supralabial scale | Small-scale agriculture | Rankine scale | moment magnitude scale | Medvedev–Sponheuer–Karnik scale | John Rankine | Hamilton Rating Scale for Depression | Claudia Rankine | Wechsler Adult Intelligence Scale | Truck scale | TORRO scale | Tanner scale | Subjective units of distress scale | ''shindo'' scale | scale (zoology) |
The limiting factors are the temperature at which the heat enters the engine, , and the temperature of the environment into which the engine exhausts its waste heat, , measured in an absolute scale, such as the Kelvin or Rankine scale.
The Rankine scale, using the degree Fahrenheit as its unit interval, is still in use as part of the English Engineering Units in the United States in some engineering fields.