constants.h File Reference

Defines physical constants and unit conversions. More...

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Namespaces
namespace	physics
	Contains physical constants and unit conversions.
namespace	physics::si
	Physical constants defined in Standard International (SI) units.
namespace	physics::imperial
	Physical constants defined in British Imperial units.
namespace	physics::us
	Physical constants defined in U.S. Customary units.
namespace	physics::conversions
	Factors and functions for unit conversions.

Functions
constexpr double	physics::conversions::fahrenheitToKelvin (double fahrenheit)
	Convert Fahrenheit to Kelvin.
constexpr double	physics::conversions::fahrenheitToRankine (double fahrenheit)
	Convert Fahrenheit to Rankine.
constexpr double	physics::conversions::fahrenheitToCelsius (double fahrenheit)
	Convert Fahrenheit to Celsius.
constexpr double	physics::conversions::mmbtuPerHrToKW (double mmbtu_per_hr)
	Converts power from MMBtu/hr to kW.
constexpr double	physics::conversions::kWToMMBtuPerHr (double kw)
	Converts power from kW to MMBtu/hr.

Variables
constexpr double	physics::si::kStefanBoltzmann = 5.670374419e-8
	Stefan–Boltzmann constant \([\unit{\watt\per\meter\squared\kelvin\tothe{4}}]\).
constexpr double	physics::si::kWaterDensityBase = 1000.0
	Standard density of water at 4°C \([\unit{\kilogram\per\meter\cubed}]\).
constexpr double	physics::si::kSpecificHeatWater = 4.1796
	Specific heat of liquid water at standard conditions \([\unit{\kilo\joule\per\kilogram\per\kelvin}]\).
constexpr double	physics::us::kOrificeAreaFactor = 1300.0
	Orifice area factor for volumetric flow calculations \([\unit{\dimensionless}]\).
constexpr double	physics::us::kAtmosphericPressurePsi = 14.7
	Standard atmospheric pressure at sea level \([\unit{psia}]\).
constexpr double	physics::us::kWaterBoilingPointF = 212.0
	Boiling point of water \([\unit{\degreeFahrenheit}]\).
constexpr double	physics::us::kSpecificHeatWaterVapor = 0.481
	Specific heat of water vapor \([\unit{\btu\per\pound\degreeFahrenheit}]\).
constexpr double	physics::us::kWaterEvaporation = 970.0
	Latent heat of evaporation for water \([\unit{\btu\per\pound}]\).
constexpr double	physics::us::kStefanBoltzmann = 1.713441e-9
	Stefan–Boltzmann constant \([\unit{\btu\per\hour\foot\squared\degreeRankine\tothe{4}}]\).
constexpr double	physics::us::kStandardGasTemperatureR = 520.0
	Standard gas temperature for exhaust calculations \([\unit{\degreeRankine}]\).
constexpr double	physics::us::kAmbientTemperatureF = 60.0
	Ambient reference temperature for exhaust calculations \([\unit{\degreeFahrenheit}]\).
constexpr double	physics::us::kSpecificHeatAirBase = 0.017828518
	Base specific heat of air \([\unit{\btu\per\pound\degreeFahrenheit}]\).
constexpr double	physics::us::kSpecificHeatAirCoeff = 0.000002556
	Temperature coefficient for specific heat of air \([\unit{\btu\per\pound\degreeFahrenheit\per\degreeFahrenheit}]\).
constexpr double	physics::us::kAirCorrectionBase = -1.078913827
	Base for air correction in exhaust gas heat loss calculations \([\unit{\btu\per\pound}]\).
constexpr double	physics::us::kWaterDensity = 8.335
	Water density \([\unit{lb/gal}]\).
constexpr double	physics::conversions::kBtuPerLbFToKJPerKgK = 4.1868
	Conversion factor from Btu/(lb·°F) to kJ/(kg·K).
constexpr double	physics::conversions::kFahrenheitToRankineOffset = 459.67
	Offset to convert Fahrenheit to Rankine.
constexpr double	physics::conversions::kHoursPerDay = 24.0
	Number of hours in a day.
constexpr double	physics::conversions::kMinutesPerHour = 60.0
	Number of minutes in an hour.
constexpr double	physics::conversions::kKilowattToBtuPerHour = 3412.136247820839
	Conversion factor from kilowatts to BTU/hr \([\unit{\btu\per\hour\per\kilowatt}]\).
constexpr double	physics::conversions::kKgPerM3ToLbPerGal = 0.0083454
	Conversion factor from kilograms per cubic meter to pounds per gallon \([\unit{\pound\per\gallon\per\kilogram\per\meter\cubed}]\).
constexpr double	physics::conversions::kMMBtuToBtu = 1'000'000.0
	Conversion factor: 1 MMBtu = 1,000,000 Btu.
constexpr double	physics::conversions::kLbPerFt3ToKgPerM3 = 16.018463
	Conversion factor: 1 pound per cubic foot = 16.018463 kilograms per cubic meter \([\unit{\kilogram\per\meter\cubed\per\pound\per\foot\cubed}]\).
constexpr double	physics::conversions::kBtuPerTonRefrigeration = 12000.0
	BTU per ton of refrigeration \([\unit{Btu/Ton}]\).

Detailed Description

https://physics.nist.gov/cuu/Constants/index.html

Definition in file constants.h.