Fluid flow phenomena are generally so complex that obtaining analytical solutions is only possible for a limited number of problems. Hence, the majority of design studies are based on the results of experimental tests involving models whose size may be smaller or bigger than that of the prototype. Nowadays, no aircraft or car is being built without an exhaustive number of model tests being performed in a wind tunnel.
Dimensional analysis and Similitude are the analytical techniques available for carrying out experimental tests in a systematic way, and expressing the results obtained in an advantageous way. Most design studies based on the results of experimental tests show clearly major benefits of tests on models, not only economic but also I terms of time. While dimensional analysis is a mathematical technique used for solving various problems belonging to all branches of engineering allowing the identification of the number and nature of the dimensionless groups that provide correspondence between model and prototype data, similitude is the theory and art of predicting prototype performance from model observations. It presents an indication of a known relationship linking the two phenomena represented by the full-size flow and another flow of smaller dimensions but with similar geometric boundaries.
The present course is trusted to answer two main questions:
- Under what conditions will the model portray the actual full scale prototype?
- How to fulfill the requirement of geometric, kinematic and dynamic similitudes between the model and the prototype?
It is intended for use by graduate engineering students as it acquaints them with the knowledge pertaining to:
- The basics of the concepts of similitude, a concept applicable to the testing of engineering models,
- The ability to applying the concepts of dimensional analysis, one of the most important mathematical tools that makes use of dimensions of physical quantities as an aid to the solutions to many engineering problems.- Enseignant: ABDELKRIM HADDAD