Introduction to complex systems

Vapor pressure calculation

In this exercise we will use a thermodynamics relation in order to calculate : vapor pressure, saturated vapor pressure, relative humidity.

in order to calculate the above variables we need to know the air temperature and the dewpoint .

P = 6.11 \times 10^{ \left( \frac{7.5\times T_d}{273.3 + T_d} \right)} \\ \quad \\ \quad \\ P_s = 6.11 \times 10^{ \left( \frac{7.5\times T}{273.3 + T} \right)} \\ \quad \\ \quad \\ R_{h} = \frac{P}{P_s} \times 100

Question

Using the above relationship define and appropriate temperature [degree Celsius], calculate: the vapor pressure, the saturation vapor pressure and the relative humidity.

Solution
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@author: yacine.mezemate
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"""
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# Here is Python script which calculate P, P_s and R_h :
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import numpy as np
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# input
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# T: the air temperature degrees Celsius
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# Td: the dewpoint degrees Celsius
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# output
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# P : vapr pressure millibars
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# Ps: saturated water pressure millibars
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# Rh: Relative humedity
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T = 20
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Td = 15
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exposantP = (7.5*Td)/(237.3 + Td)
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P = 6.11 * np.power(10, exposantP)
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exposantPs = (7.5*T)/(237.3 + T)
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Ps = 6.11 * np.power(10, exposantPs)
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Rh = (P/Ps)*100
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print("Vapr pressure: %d"%P , "Saturated water pressure: %d" %Ps , "Relative humedity: %d " %Rh)
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Question
For different values of 
		
	 and 
		
	 plot P(T).
Hint
Put the above script in loop for different values of 
		
	
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