Rankine scale

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Rankine temperature conversion formulae
from Rankine to Rankine
Celsius [°C] = ([°R] − 491.67) × 59 [°R] = ([°C] + 273.15) × 95
Fahrenheit [°F] = [°R] − 459.67 [°R] = [°F] + 459.67
Kelvin [K] = [°R] × 59 [°R] = [K] × 95
For temperature intervals rather than specific temperatures,
1 °R = 1 °F = 59 °C = 59 K
Comparisons among various temperature scales

The Rankine scale (/ˈræŋkɪn/) is a thermodynamic temperature based on an absolute scale named after the Glasgow University engineer and physicist William John Macquorn Rankine, who proposed it in 1859. (The Kelvin scale was first proposed in 1848.)[1]

The symbol for degrees Rankine is °R[2] (or °Ra if necessary to distinguish it from the Rømer and Réaumur scales). By analogy with kelvin, some authors term the unit rankine, omitting the degree symbol.[3][4] Zero on both the Kelvin and Rankine scales is absolute zero, but a temperature difference of one Rankine degree is defined as equal to one Fahrenheit degree, rather than the Celsius degree used on the Kelvin scale. A temperature of −459.67 °F is exactly equal to 0 °R.

The US National Institute of Standards and Technology recommends against using the degree symbol when citing Rankine in NIST publications.[2]

Some important temperatures relating the Rankine scale to other temperature scales are shown in the table below.

Kelvin Celsius Fahrenheit Rankine
Absolute zero
(by definition)
0 K −273.15 °C −459.67 °F 0 °R
Freezing point of brine
(by definition (on Fahrenheit scale only))
255.37 K −17.78 °C 0 °F 459.67 °R
Freezing point of water[5] 273.15 K 0 °C 32 °F 491.67 °R
Triple point of water
(by definition)
273.16 K 0.01 °C 32.018 °F 491.688 °R
Boiling point of water[6] 373.1339 K 99.9839 °C 211.97102 °F 671.64102 °R

Conversion table between the temperature units[edit]

Kelvin


Celsius


Fahrenheit


Rankine scale


Rømer scale


Newton scale


Delisle scale


Réaumur scale

See also[edit]

Notes and references[edit]

  1. ^ http://www.merriam-webster.com/dictionary/rankine
  2. ^ a b B.8 Factors for Units Listed Alphabetically from Guide for the Use of the International System of Units (SI), NIST Special Publication 811, 2008 edition, Ambler Thompson and Barry N. Taylor
  3. ^ Pauken, Michael (2011). Thermodynamics For Dummies. Indianapolis: Wiley Publishing Inc. p. 20. ISBN 978-1-118-00291-9. 
  4. ^ Balmer, Robert (2011). Modern Engineering Thermodynamics. Oxford: Elsevier Inc. p. 10. ISBN 978-0-12-374996-3. 
  5. ^ The ice point of purified water has been measured to be 0.000089(10) degrees Celsius – see Magnum, B.W. (June 1995). "Reproducibility of the Temperature of the Ice Point in Routine Measurements" (PDF). Nist Technical Note. 1411. Retrieved 2007-02-11. 
  6. ^ For Vienna Standard Mean Ocean Water at one standard atmosphere (101.325 kPa) when calibrated solely per the two-point definition of thermodynamic temperature. Older definitions of the Celsius scale once defined the boiling point of water under one standard atmosphere as being precisely 100 °C. However, the current definition results in a boiling point that is actually 16.1 mK less. For more about the actual boiling point of water, see VSMOW in temperature measurement.

External links[edit]