Department Seminar of Yakir Oded - Spherical Bi-Stable Rotating Compliant Mechanism for Autonomous Backwash of UF Membrane

School of Mechanical Engineering Seminar
Wednesday, November 6, 2023 at 14.00
Zoom Seminar

Spherical Bi-Stable Rotating Compliant Mechanism for Autonomous Backwash of UF Membrane

Oded Yakir

M.Sc. student of Prof. Hadas Mamane

The water energy lab

Potable water availability is an ongoing problem in many parts of the world. Many technological advances have been made to improve on the matter, yet for many, salvation is out of sight. Due to the scale of the problem, any small improvement in a system or a component of a system has the potential to have a major impact on the lives of millions of men, women, and children who otherwise would have to consume contaminated water. Although a large-scale water treatment plant is an expensive and complex infrastructure, small-scale water purification systems do not have to be. Effective and affordable membrane filters are becoming available for both small and medium-scale systems. When it comes to small local water treatment systems, it is often expected that the user (or someone appointed by him) will maintain the system, whether it includes a mandatory filter cleaning cycle or any other work needed for the system to remain operational. System maintenance is a major setback for implementation in the developing world.

In this work, a novel mechanical valve is designed and presented to automate the backwash protocol in ultrafiltration membranes, thus allowing for the application of highly affordable point-of-use self-cleaning water purification systems capable of eliminating all biological contamination and mitigating the main risk factors in diarrhea and dysentery in the developing world. The load-displacement relationship of a bistable compliant mechanism is tuned and applied to both (a) sense threshold differential pressures associated with the need for backwash cleaning and (b) actuate valves to reconfigure the hydraulic flow within the device to produce the backwash or filtration modes. In the development of the resultant valve, design options were explored, finite element analysis (FEA) was undertaken, prototypes were fabricated and analyzed experimentally. Experimental results showed that the bistable valve is indeed capable of automating a backwash protocol for an ultrafiltration membrane.

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https://tau-ac-il.zoom.us/j/86497933118