NUCLEAR MAGNETIC RESONANCE LEVEL GAUGING DEVICE

摘要

An NMR level gauging device comprising two sets of coils (2, 3) wound orthogonal to one another about a tank (1). Each set is spaced apart about the tank (1) so as to be capable of providing a substantially uniform magnetic field through the tank when an electric current passes through them. A steady dc current being supplied to coils (2) from a supply (4) and an oscillating electromagnetic field at one or more fixed frequencies is supplied to coils (3) from supply (5); the sets of coils (2, 3) together providing for a substantially position independent sampling of a substance of interest i.e.g. fuel, within the tank (1). Detection means (6, 7) are provided for detecting the amplitude of an induced resonance signal in the substance of interest and to provide an amplitude dependent output as a gauge of the amount of substance in the tank (1).