Rule of Thumb

LOOKING FOR ENGINEERING CORRELATIONS

If you are trying to describe a phenomenon rigorously, correlate aggregate parameters in such a way that all the units ...

If you are trying to describe a phenomenon rigorously, correlate aggregate parameters in such a way that all the units cancel out. For example, don’t study the effect of changing pipe diameter, which has units of distance. Study changes of pipe diameter divided by pipe length, which has units of distance divided by distance. The result is dimensionless. These correlations are more resilient to changes in materials and scale. — David R. Throop, chemical engineer, Austin, Texas

10/12/18