text: Recent advance in LFV made it possible for metering flow velocity of media which has very low electroconductivity, particularly by varying parameters as well as using some state-of-art force measurement devices enable to measure flow velocity of electrolyte solutions with conductivity that is 10 times smaller than that for the liquid metals. There are variety of industrial and scientific applications where noncontact flow measurement through opaque walls or in opaque liquids is desirable. Such applications include flow metering of chemicals, food, beverages, blood, aqueous solutions in the pharmaceutical industry, molten salts in solar thermal power plants, and high temperature reactors   as well as glass melts for high-precision optics.
  A noncontact flowmeter is a device that is neither in mechanical contact with the liquid nor with the wall of the pipe in which the liquid flows. Noncontact flowmeters are equally useful when walls are contaminated like in the processing of radioactive materials, when pipes are strongly vibrating or in cases when portable flowmeters are to be developed. If the liquid and the wall of the pipe are transparent and the liquid contains tracer particles, optical measurement techniques, are effective enough tool to perform noncontact measurements. However, if either the wall or the liquid are opaque as is often the case in food production, chemical engineering, glass making, and metallurgy, very few possibilities for noncontact flow measurement exist.
  The force measurement system is an important part of the Lorentz force velocimetry. With high resolution force measurement system makes the measurement of even lower conductivity possible. Up to date has the force measurement system continually being developed.   At first the pendulum-like setups was used (Figure 5). One of the experimental facilities consists of two high power (410 mT) magnets made of NdFeB suspended by thin wires on both side of channel thereby creating magnetic field perpendicular to the fluid flow, here deflection is measured by interferometer system,. The second setup consists of state-of-art weighting balance system (Figure 6) from which is being hanged optimized magnets on the base of Halbach array system. While the total mass of both magnet systems are equal (1 kg), this system induces 3 times higher system response due to arrangement of individual elements in the array and its interaction with predefined fluid profile. Here use of very sensitive force measuring devices is desirable, since flow velocity is being converted from the very tiny detected Lorentz Force. This force in combination with unavoidable dead weight  of the magnet () is around . After that, the method of differential force measurement was developed. With this method two balance were used, one with magnet and the other is with same-weight-dummy. In this way the influence of environment would be reduced. Recently, it have been reported that the flow measurements by this method is possible for saltwater flows whose electrical conductivity is as small as 0.06 S/m (range of electrical conductivity of the regular water from tap).