Permeability (constant / falling head) calculator

Inputs in the worked example

The live calculator starts with these values; change any of them and every result, check and diagram updates instantly.

Worked example — results

• ✓ Test type suits soil (falling head for k < 1e-5 m/s)

Method, formulas and assumptions

• k = (a·L)/(A·t) · ln(h1/h2)
• k20 = kT · ηT/η20
• Units converted cm/s → m/s

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