Search results
Results from the WOW.Com Content Network
The Template:Heat_index calculates the heat index, for a specified temperature and relative humidity (parameters 1 & 2), using a formula from the U.S. National Weather Service (NWS). [ 1 ] Science
The heat index (HI) is an index that combines air temperature and relative humidity, in shaded areas, to posit a human-perceived equivalent temperature, as how hot it would feel if the humidity were some other value in the shade. For example, when the temperature is 32 °C (90 °F) with 70% relative humidity, the heat index is 41 °C (106 °F ...
The RTI is the rounded temperature in degrees C, at which the properties of B have decreased to 50 percent of their initial value in about the same amount of time (correlation time) than it takes for A at its own RTI value. A maximum correlation time of 60.000 hours is considered acceptable for many electrical applications, however it may also ...
When the temperature is 30 °C (86 °F) and the dew point is 15 °C (59 °F), the humidex is 34. If the temperature remains 30 °C (86 °F) and the dew point rises to 25 °C (77 °F), the humidex rises to 42. The humidex is higher than the U.S. heat index at equal temperature and relative humidity. The humidex formula is as follows: [7] [8]
The representation is made on a temperature-relative humidity, instead of a standard psychrometric chart. The comfort zone in blue represents the 90% of acceptability, which means the conditions between -0.5 and +0.5 PMV, or PPD < 10%.
The AT index used here is based on a mathematical model of an adult, walking outdoors, in the shade (Steadman 1994). The AT is defined as the temperature, at the reference humidity level, producing the same amount of discomfort as that experienced under the current ambient temperature and humidity. [6] The formula [7] is:
A temperature coefficient describes the relative change of a physical property that is associated with a given change in temperature. For a property R that changes when the temperature changes by dT , the temperature coefficient α is defined by the following equation:
using Plots # Saturated water vapor pressure [Pa] # See Ham, 2005. Useful Equations and Tables in Micrometeorology function water_vapor_saturated_pressure (Ta, P) Ta = Ta-273.15 es = (1.0007 + (3.46e-5 * (P / 1e3))) * 0.61121 * exp ((17.502 * Ta) / (Ta + 240.97)) * 1e3 return es end function water_vapor_density (e, Tair) Rs_v = 461.5 # J/(kg.K) specific gas constant for water vapor ρv = e ...