Force Balance Calibration and the Modern Design of Experiments

The University of Georgia High-Speed Water Tunnel (HSWT) is a closed-loop water tunnel primarily used to study fluid-structure interaction. A force balance is used to measure forces on models within the HSWT. The force balance is a key instrument in many hydrodynamic experiments, so it is necessary to design a robust calibration process for the balance. This thesis documents the development of a calibration experiment that follows the Modern Design of Experiments (MDOE) methodology. MDOE is a process for designing, executing, and analyzing experiments using quality assurance techniques to guard against systematic error. To validate the calibration, the balance is used to compute lift and drag coefficients for a plate at various angles of attack. Predictions made with the balance were consistent with published results, indicating that the instrument is reliable. This investigation is relevant because improving the force balance increases the capabilities of the water tunnel.