Wall shear stress is one of the most essential scaling parameters used in fluid dynamics. It is significant because it helps us compare results in different experimental studies. The accurate measurements of wall shear stress will be instrumental in improving the existing empirical models and validating CFD models. Wall shear stress is also vital in improving fuel efficiency, heat transfer efficiency, and aerodynamic efficiency in real-world applications. This work discusses the design and implementation of a prototype floating element balance — a direct method of wall shear measurement. The direct measurement methods are robust and can significantly improve the validity of experimentation when perfected. In this work, a prototype floating element balance is designed and developed to estimate the wall shear stress in a smooth wall pilot facility to assess its feasibility for large-scale development. The floating element balance utilizes a strain gauge to estimate the wall shear stress. The preliminary tests show promising results, revealing potential design improvements. A strain measurement study is conducted to investigate the force-strain relationship and the reliability of the balance, which highlights the long-term stability and consistency in the strain measurement. However, further investigations are required into the drift response of the floating element balance. The strain measurements are also employed to calibrate the balance using a linear curve fit with a coefficient of determination of R^2 = 0.99, indicating a satisfactory linear estimation. / Master of Science / Drag is a phenomenon that occurs when the surface of a solid body interacts with a fluid. In fluid mechanics, there are two fundamental types of drag forces: pressure and skin friction. Pressure drag occurs due to the shape of the body, creating a pressure difference across the body, while skin friction drag arises due to the dominant viscous nature of the fluid. Understanding these forces is vital in improving the aerodynamic efficiency of various devices. Also, these forces play an essential role in the fuel efficiency and performance of the vehicles. The measurement of pressure drag is relatively straightforward compared to the skin friction drag. However, the measurement of skin friction drag can pose a challenge due to its smaller magnitude than the pressure drag. The importance of skin friction is due to its physical properties, which allow us to compare different experimental results and understand details about the turbulence in the flow. Also, accurate information on skin friction would improve existing relationships in fluid mechanics, and this information is also utilized to validate mathematical models in fluid mechanics. This work presents the design and implementation of a prototype used to estimate skin friction in a smooth wall facility using a novel and robust measurement known as floating element skin friction balance. Preliminary tests are conducted to assess the viability of the floating element balance for a large-scale development, which shows promising results while underlining some inherent limitations in the design and performance.

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