Spinning disc tests

A similar method of test was used at the International Nickel Company s Corrosion Laboratory at North Carolina. The specimen discs are mounted on insulated vertical spindles and submerged in sea-water, which is supplied continuously to the tank in which the specimens are immersed. The maximum peripheral speed of the spinning disc is about 760cms , and the characteristic pattern of attack is shown in Fig. 19.3a. Studies of variation of depth of attack with velocity indicate that at low velocities (up to about 450 cm s ) alloys such as Admiralty brass, Cu-lONi and cupro-nickel alloys containing iron maintain their protective film with a consequent small and similar depth of attack for the diflferent alloys. At higher velocities the rate increases due to breakdown of the film. 

The use of a rotating reactor to provide efficient mixing has been proposed and tested for viscous polymerizations and acid-catalysed rearrangement reactions [6], The principle of these spinning disc reactors is that the centrifugal force... 

Spinning disc technology, as used in the SDR, has been tested on foodstuffs. In particular, it has been used for dehydration of food, and has been proposed for rapid pasteurisation of heat-sensitive liquid foods, fii Figure 10.5 the SDR is illustrated heating treacle. The good mixing characteristics and excellent heat transfer are evident in the highly uniform temperature distribution across the disc. 

The idea of utilizing a coefficient of friction is not new, having been proposed and tested for the cleaning of flat plates with air at least two decades ago by Zimon.f l Similar ideas have been proposed for the cleaning of wafers/discs by spinning them.t If the particles that... 

Murkes has reported tests with the same American dynamic filter, except that he eliminated cake formation altogether by spinning the discs faster. No visible abrasion of the medium was observed while the filtration velocities could be maintained high even at relatively low pressures, below 5 bar. Murkes showed clearly the effect of speed and number of rotor vanes on filtration velocities and specific energy input. His results show, for any number of rotor vanes, an increase in specific energy input (kWh per m of filtrate) with rotor speed this increase can be minimized by optimization of... 

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