2015-05-15 19:10:46 +00:00
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/*
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* Author: Ruthberg
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*
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* Calculates wet bulb based on temperature and relative humidity
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*
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* Arguments:
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2015-05-16 09:12:29 +00:00
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* 0: temperature - degrees celcius <NUMBER>
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* 1: pressure - hPa <NUMBER>
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* 2: relativeHumidity - value between 0.0 and 1.0 <NUMBER>
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2015-05-15 19:10:46 +00:00
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*
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* Return Value:
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* 0: wet bulb <NUMBER>
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*
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* Return value:
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* None
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*/
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#include "script_component.hpp"
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2015-05-16 09:12:29 +00:00
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private ["_es", "_e", "_eDiff", "_eGuessPrev", "_cTempDelta", "_twGuess", "_eguess"];
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PARAMS_3(_temperature,_pressure,_relativeHumidity);
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// Source: http://cosmoquest.org/forum/showthread.php?155366-Calculating-Wet-Bulb-Temperature-from-RH-amp-Dry-Bulb
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_es = 6.112 * exp((17.67 * _temperature) / (_temperature + 243.5));
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_e = _es * _relativeHumidity;
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_eDiff = _es - _e;
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_eGuessPrev = _es;
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_cTempDelta = 3.3145;
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_twGuess = _temperature;
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for "_j" from 1 to 50 do {
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_twGuess = _twGuess - _cTempDelta;
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_eguess = 6.112 * exp((17.67 * _twGuess) / (_twGuess + 243.5));
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_eguess = _eguess - (_pressure * (_temperature - _twGuess) * 0.00066 * (1 + (0.00115 * _twGuess)));
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_eDiff = _eguess - _e;
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if (abs(_eDiff) <= 0.001) exitWith {};
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_cTempDelta = _eDiff / ((_eguessprev - _eguess) / _cTempDelta);
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_eguessprev = _eguess;
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};
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2015-05-15 19:10:46 +00:00
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2015-05-16 09:12:29 +00:00
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_twGuess
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