lsi.py

# Read more: http://www.lenntech.com/calculators/langelier/index/langelier.htm#ixzz4bbswoh9P


import math  # This will import math module
import platform
import os


def clear_screen():
    # clear the terminal either in windows or *nix
    if platform.system() == "Windows":
        os.system("cls")
    else:
        os.system("clear")

    myos = platform.system()

    print("Hey, you appear to be running: ", myos)
    print()


# Simple F to C converter. It works!
Celsius = input("Enter a temperature in Celsius: ")
Fahrenheit = 9.0 / 5.0 * float(Celsius) + 32
print("Temperature:", Celsius, "Celsius = ", Fahrenheit, " F")
# the reverse calc
revc = (Fahrenheit - 32) * 5.0 / 9.0
print("and the check. here is Deg C back: ", revc)

print(
    "The following program developed from \n http://www.corrosion-doctors.org/Cooling-Water-Towers/Index-Lang-calcul"
    ".htm "
)
print("Enter values for the following inputs")
print("------------------")
# easy space
print()
# command line input with a default value. Must convert input to number, here a float
temp = float(input("Enter Temperature in Deg F [77]: ") or 77)
tds = float(input("Enter TDS in mg/l [320]: ") or 320)
ca = float(input("Enter Ca2+ in mg/l [150]: ") or 150)
pH = float(input("Enter pH [7.5]: ") or 7.5)
alk = float(input("Enter Alkalinity as CaCO3 [34]: ") or 34)

# convert F to C
degc = ((temp) - 32) * 5.0 / 9.0
# compute the TDS index
A = (math.log10(tds) - 1) / 10
print("TDS = ", tds, " --> The TDS index is: ", A)

# compute the temperature index
B = -13.12 * (math.log10(degc + 273)) + 34.55
print("Deg C = ", degc, " --> The temp index is: ", B)

# compute the hardness index
C = math.log10(ca) - 0.4
print("Calcium Hardness = ", ca, " --> The hardness index is: ", C)

# compute the alkalinity index
D = math.log10(alk)
print("Alklinity = ", alk, " --> The alkalinity index is: ", D)

# compute the pHs
pHs = (9.3 + A + B) - (C + D)
print("pHs = ", pHs)

# compute the LSI
LSI = pH - pHs
print("LSI = ", LSI)

# Now we interpret the results for the user

print()

if LSI <= -0.5:
    print(
        "Serious corrosion. Water is undersaturated with respect to calcium carbonate. Undersaturated water has a "
        "tendency to remove existing calcium carbonate protective coatings in pipelines and equipment."
    )
elif -0.499 <= LSI < 0:
    print(
        "Slightly corrosive, but non-scale forming. Water is undersaturated with respect to calcium carbonate. "
        "Undersaturated water has a tendency to remove existing calcium carbonate protective coatings in pipelines "
        "and equipment."
    )
elif LSI == 0:
    print(
        "Balanced but pitting corrosion possible. Water is considered to be neutral. Neither scale-forming nor scale removing."
    )
elif -0.0001 <= LSI < 0.5:
    print(
        "Slightly scale forming. Water is supersaturated with respect to calcium carbonate (CaCO3) and scale forming may occur."
    )
else:
    print(
        "Scale forming, but non-corrosive. Water is supersaturated with respect to calcium carbonate (CaCO3) and scale forming may occur."
    )
print()
print("Done!")