Last updated: 11 May 2016 Turbidity as a surrogate for suspended sediment concentration (SSC) is commonly used and deeply established in practice. The shortcomings of turbidity as a surrogate for SSC are: The calibration changes with grain size; The calibration changes with sediment color; and Turbidity...
LISST-Infinite installed next to a draft tube. Sequoia’s LISST-Infinite instrument is made to protect turbines by sounding alarms so that plant operators may decide to shut down power production and save turbines from abrasive damage. The instrument system consists of a mechanism to deliver...
Click here for a link to PiE 2016 Daniel M. Hanes, Colin Jago, Ole Mikkelsen, and Yogesh C. Agrawal With the recent announcement that a fifth “Particles in Europe” (PiE) conference will be held in Budapest in Fall, 2016, it would be useful to the community of potential participants to review the...
[Readers should be aware that due to the different nature of size dependence of optical and acoustic backscatter sensors, changes in grain size distribution can cause the two data to not track. Neither sensor holds calibration with changing grain size. The LISST-ABS does hold calibration for grains...
PRELIMINARY ANNOUNCEMENT The 5th PiE Conference will be held in Budapest at the Budapest University of Technology and Economics. The University is co-sponsoring the conference along with Sequoia Scientific, Inc. Assoc. Prof. Sándor Baranya is the local conference co-chair in Budapest. The 3-day conf....
Waterways, Maintenance Dredging, and Contaminated Sediment Removal Dredging is essential for creation or maintenance of navigation channels, as well as for removing contaminated sediments. The contamination of water by dredged sediments is regulated in most developed, and some developing countries....
Sequoia manufactures two instruments based on laser diffraction for monitoring sediments entering hydro turbines. These are the LISST-Hydro and LISST-Infinite. These two produce data on sediment concentration sorted into 3 size classes – fine (<75μm), medium (75 to 200 μm), and coarse (200 to...
The LISST-ABS would reveal rich sediment structure that turbidity misses. For measuring suspended sediments, the use of optical backscatter sensors or other turdibity sensors is widespread. At the same time, it is understood that these sensors respond to total particle area, not volume or mass. In other...
This Note is written for those users who wish to get a deeper understanding of acoustic backscattering and its use in the LISST-ABS. It expands on the very simple page, How LISST-ABS Works. What follows is a description of coherent and incoherent scattering, strength of scattering of sound by particles...
Updated: 4 March 2016. INTRODUCTION: Sequoia’s Acoustic Backscatter Sensor, LISST-ABS is designed to measure suspended sediment concentration at a point. Unlike ADCP’s which may record similar backscatter strength at multiple points (‘ranges’) along acoustic beams, the LISST-ABS ...