Load Cell for Wind Tunnel Testing

A procedure using scale models loaded by fan-driven airflow to predict responses of a structure, structural components, and cladding to actual wind storm conditions. 

For Wind Tunnel Testing, compression load cells are used. The column or canister-style load cell is a traditional illustration of a compression load cell. Usually cylindrical in shape, these have mounting surfaces on both the top and bottom ends. The weight-bearing component is a central core or column located inside. Strain gauges, which are oriented to detect deformations under load, are bonded to the surface of this column. The load cell is often enclosed in an exterior sheath to shield its internal components from the elements. Many are used in severe or hazardous conditions and are hermetically sealed. These load cells are reliable and precise options that work well for high-capacity static weighing applications. It’s imperative that the cells are correctly and aligned during installation to guarantee precise measurements. This is usually accomplished by attaching them to mounting gear that has been properly made.

Button load cells are another popular design for compression load cells. They are small and low profile and are frequently used in test and measurement applications. Doughnut or thru-hole load cells also include a central opening that allows the apparatus to flow through. An instance of this kind of application can be found in an oil and gas industry pump monitoring system. A compression load cell is essentially a block intended to support a load at a single location in order to detect compression. Compression load cells measure a pushing force along a single axis, whereas tension load cells measure a pulling force. A compression load cell is often positioned underneath the object that has to be measured. As was previously noted, when a load is applied, the strain gauge in a compression load cell deforms, and this deformation is used to create the measurement. Compression load cells are employed, depending on the application, to measure any relative resistance changes. These relative changes can be measured very precisely with the Wheatstone bridge circuit, providing accurate findings.

S-type load cells are mostly used to measure tensile forces, though they can also be used to measure compressive forces like in wind tunnel testing. As the name implies, these load cells have an S-shaped design. The spring element is located in the center beam of the load cell. This element is a metal part that, when stressed, deformed elastically and, when the stress is released, returns to its original shape. This deformation or strain is detected by strain gauges installed on the spring element, which convert it into an electrical output. Tension or compression causes the spring element in S-type load cells to distort at both ends. Unlike other types of load cells, S-type load cells can be calibrated in both weight and Newton units since they are commonly used as force transducers.