Cavitation Treatment Unit

The Problem

The requirement for a clean, safe alternative to chemicals led to the idea of the use of high energy imploding cavitation for killing unwanted organisms in ship’s Ballast Water which required the development of a suitable unit to harness these forces.

The Approach

The analysis focused on developing and optimising the design of a suitable unit involving transient multiphase flow and cavitation and many geometrical designs capable of reducing the static pressure of the water flow to vapour pressure and then back again were analysed. The goal was to do this with the minimum pressure losses whilst harnessing the maximum amount of energy from the cavitation.

The Result

Following much iteration, manufacturing of prototypes, experimental tests and comparisons, a final design was chosen which in combination with several other elements of the system provided results that were within the strict regulations set by the Institute of Maritime Organisation (IMO). The design of a device with an acceptable pressure loss whilst maximising the amount of energy extracted from the cavitating water had been achieved. This unit was accepted as a solution which then evolved into a full scale product.