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Log-Normal Distribution Parameters from Median Diameter and Geometric Standard Deviation

Calculates the natural‑log mean (μ) and log‑standard deviation (σ) of a log‑normal particle‑size distribution from the median diameter (x₅₀) and geometric standard deviation (σg).

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1. Define Input Parameters

2. Engineering Output

Natural‑log mean of the distribution (mu)
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Log‑standard deviation of the distribution (sigma)
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Context & Assumptions

In process engineering, the median particle size and geometric standard deviation are often reported for powders. Converting these industrial descriptors to the statistical parameters μ and σ enables simulation, Monte‑Carlo analysis, and analytical calculation of percentiles for the PSD.

Understand the Engineering Principles

Review the step-by-step derivations, typical industrial limits, and scale-up rules.

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