User:Milton Beychok/Sandbox: Difference between revisions

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Given an air pollutant concentration at sea-level atmospheric pressure, the concentration at higher altitudes can be obtained from this equation:
Given an air pollutant concentration at sea-level atmospheric pressure, the concentration at higher altitudes can be obtained from this equation:


<math>C_\mathrm h = C_0\,\cdot\bigg(\frac{T_0 - 6.5 h}{T_0}\bigg)^{5.2558}</math>


:<math>C_\mathrm h = C_0\,\cdot\bigg(\frac{T_0 - 6.5 h}{T_0}\bigg)^{5.2558}</math>
where:
 
{| border="0" cellpadding="2"
{| border="0" cellpadding="2"
|-
|align=right|where:
|&nbsp;
|-
|-
!align=right| '''''L'''''
!align=right| '''''L'''''
|align=left|= atmospheric temperature lapse rate = 6.5 K/km
|align=left|= atmospheric temperature lapse rate = 6.5 K&thinsp;/&thinsp;km
|-
|-
!align=right| '''h'''
!align=right| '''h'''
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|-
|-
!align=right| '''''g'''''
!align=right| '''''g'''''
|align=left|= Earth's surface gravitational acceleration = 9.80665 m/s<sup>2</sup>
|align=left|= Earth's surface gravitational acceleration = 9.80665 m&thinsp;/&thinsp;s<sup>2</sup>
|-
|-
!align=right| '''''M'''''
!align=right| '''''M'''''
|align=left|= Molecular weight of air = 28.9644 g/mol  
|align=left|= Molecular weight of air = 28.9644 g&thinsp;/&thinsp;mol  
|-
|-
!align=right| '''''R'''''
!align=right| '''''R'''''
|align=left|= Universal gas constant = 8.314472 J/(mol&thinsp;•&thinsp;K)
|align=left|= Universal gas constant = 8.314472 J&thinsp;/&thinsp;(mol&thinsp;•&thinsp;K&thinsp;)
|-
|-
!align=right| '''''P'''''<sub>&thinsp;0</sub>
!align=right| '''''P'''''<sub>&thinsp;0</sub>
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|align=left|= absolute atmospheric pressure at altitude h (in the same pressure units as '''''P'''''<sub>&thinsp;0</sub>)
|align=left|= absolute atmospheric pressure at altitude h (in the same pressure units as '''''P'''''<sub>&thinsp;0</sub>)
|-
|-
!align=right| '''''C'''''
!align=right| '''''C'''''<sub>&thinsp;0</sub>
|align=left|= Air pollutant concentration, in mass per unit volume at sea level atmospheric pressure '''''P'''''<sub>&thinsp;0</sub> and specified temperature '''''T'''''<sub>0</sub> (commonly 288.15 K)
|align=left|= Air pollutant concentration, in mass per unit volume at sea level atmospheric pressure '''''P'''''<sub>&thinsp;0</sub> and specified temperature '''''T'''''<sub>0</sub> (commonly 288.15 K&thinsp;)
|-
|-
!align=right| '''''C'''''<sub> h</sub>
!align=right| '''''C'''''<sub> h</sub>
|align=left|= Concentration, in mass per unit volume at altitude '''h''' and specified temperature '''''T'''''<sub>0</sub>  
|align=left|= Concentration, in mass per unit volume at altitude '''h''' and specified temperature '''''T'''''<sub>0</sub>  
|}
|}

Revision as of 02:05, 28 August 2011

which, for the parameter values below, then becomes:

Given an air pollutant concentration at sea-level atmospheric pressure, the concentration at higher altitudes can be obtained from this equation:

where:

L = atmospheric temperature lapse rate = 6.5 K / km
h = altitude, km
g = Earth's surface gravitational acceleration = 9.80665 m / s2
M = Molecular weight of air = 28.9644 g / mol
R = Universal gas constant = 8.314472 J / (mol • K )
P 0 = absolute atmospheric pressure at sea level (in any selected pressure units)
P h = absolute atmospheric pressure at altitude h (in the same pressure units as P 0)
C 0 = Air pollutant concentration, in mass per unit volume at sea level atmospheric pressure P 0 and specified temperature T0 (commonly 288.15 K )
C h = Concentration, in mass per unit volume at altitude h and specified temperature T0