Abstract of "THE EFFECT OF A PERMANENT MAGNET ON SCALE FORMATION IN A TUBE"

DOI: 10.1615/ICHMT.2000.TherSieProcVol2.480
125 pages

W. Reinaldo Da Veiga
Department of Mechanical and Manufacturing Engineering, Rand Afrikaans University, PO Box 524, Auckland Park, 2006, Johannesburg, South Africa

Josua Petrus Meyer
Department of Mechanical and Aeronautical Engineering, University of Pretoria, Pretoria, Private Bag X20, Hatfield, 0028, South Africa

Abstract

An experimental investigation is described in which an experimental set-up and measuring technique are developed. It is used to evaluate a permanent magnet for the decrease of scale formation in tubes. The volumetric flow rate is used as the indicator of scale formation, which relies on the basic principle that the friction pressure drop increases if scaling takes place. The test section consists of three soft-drawn copper tubes in which water with a velocity of ± 2 m/s flows. One of the tubes is used to evaluate the Physical Water Treatment (PWT) device and the other two tubes are used as a control. With the experimental set-up described it is possible to detect a change in the friction factor of 1% which represents a flow rate change of 22 ml/min. Experiments are conducted in different phases in which the PWT device is placed onto one of the tubes and then removed to determine if any change in the scale formation rate takes place. It follows from the results obtained that a very sensitive experimental set-up was designed and built which can be used to evaluate the efficiency of PWT devices. It can also be deduced that the magnet has an influence on scale formation.