Surface Shear Force Comparator

DESCRIPTION

The Shear Comparator (19 cm x 20 cm x 1.8 cm) allows users to compare the shear stress (i.e., skin friction) of two different test surfaces in a variety of flow conditions. The sensor has two identical floating elements (4 cm x 7 cm), on which two test surfaces (thickness < 1 mm) can be attached. The floating elements, which can only be displaced in one direction, are side by side so that both test surfaces experience the same flow conditions. Two optical encoders measure the displacement of each floating element which is proportional to the shear force each test surface experiences. The low-profile sensor is intended to be placed below the surface at the target position while keeping the test surfaces flush with the surrounding surface.

APPLICATIONS

Shear measurement or comparison of two test surfaces in various flow conditions:

● Towing tanks; underneath watercrafts; water tunnels

● Wind tunnels; on aircraft wings

OPTIONS

Packaging:

● Paper box and packaging air film

● Optical encoder covered with silicone sealant  

Customization:

● Floating elements: size and spring constant

PUBLICATION

Xu, M., Arihara, B., Tong, H. et al. A low-profile wall shear comparator to mount and test surface samples. Exp Fluids 61, 82 (2020). https://doi.org/10.1007/s00348-020-2922-z