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Design of Machine Elements / July 17, 2021

Sommerfeld number

In the design of fluid bearings, the Sommerfeld number (S) is a dimensionless quantity used extensively in hydrodynamic lubrication analysis. The Sommerfeld number is very important in lubrication analysis because it contains all the variables normally specified by the designer. The Sommerfeld number is named after Arnold Sommerfeld (1868–1951). Definition The Sommerfeld Number is typically defined by the following equation. Derivation Petroff’s Law

By · July 17, 2021 · 1 min read

In the design of fluid bearings, the Sommerfeld number (S) is a dimensionless quantity used extensively in hydrodynamic lubrication analysis. The Sommerfeld number is very important in lubrication analysis because it contains all the variables normally specified by the designer.

The Sommerfeld number is named after Arnold Sommerfeld (1868–1951).

Definition

The Sommerfeld Number is typically defined by the following equation.

Derivation

Petroff’s Law