Vapour-pressure deficit temperature, the relative humidity and, if possible, the canopy air temperature. We must then compute the saturation pressure. Saturation pressure can be looked up in a psychrometric chart or derived from the Arrhenius equation, a way to compute it directly from temperature is where: To convert between Rankine and degrees Fahrenheit: formula_10 We compute this pressure for both the ambient and canopy temperatures. We then can compute the actual partial pressure of the water vapour in the air by multiplying by the relative humidity [%]: and finally VPD using formula_12 or formula_13 when the canopy temperature is known. Vapour-pressure deficit
Mercury vapour turbine the steam plant. On maintained full-load the heat output averages 9800 BTU per net kWh [34.8% efficiency]. It is believed that maintenance costs will be lower than in ordinary steam plant. The back-pressure on the mercury turbine is fixed by the steam boiler pressure; only a small vacuum pump is needed, as there is no air or other gas in the mercury system. Power plants designed by William Le Roy Emmet were constructed by General Electric and operated between 1923 and 1950. Large plants included: Mercury vapour turbine A mercury vapour turbine is a form of heat engine that uses