CBE 30355 - Lecture Notes - Oct. 4, 2018

Announcements

Class notes

The main points of the lecture were

• Dynamic Similarity

Goals:

• Render the equations of motion dimensionless.
• Apply the law of dynamic similarity to develop scale models.

Reading

• The class notes.
• BS&L, chapter 3

Additional Readings:

A classic example of the use of dynamic similarity and the laws governing scale-up is the design of ships. In the U.S. the main ship model design and testing center is the former David Taylor Model Basin (now the Carderock Division of the Naval Surface Warfare Center). While you can't really keep the Reynolds number constant between model and the full scale ship, you can keep the Froude number constant. This allows you to see how hull design, etc., affects bow waves, wakes, and drag. Provided the Reynolds number is "high" for both model and full scale (so that viscous effects can be neglected), the drag on the model can be related to that on the full scale ship. The history of the model basin may be found in an ASME brochure given here.

Demonstration:

Dynamic Similarity of Vortices