text: Time-of-flight Lorentz force velocimetry, is intended for contactless determination of flow rate in conductive fluids. It can be successfully used even in case when such material properties as electrical conductivity or density are not precisely known under specific outer conditions. The last reason makes time-of-flight LFV especially important for industry application. According to time-of-flight LFV (Fig. 9) two coherent measurement systems are mounted on a channel one by one. The measurement is based on getting of cross-correlating function of signals, which are registered by two magnetic measurement's system. Every system consists of permanent magnet and force sensor, so inducing of Lorentz force and measurement of the reaction force are made simultaneously. Any cross-correlation function is useful only in case of qualitative difference between signals and for creating the difference in this case turbulent fluctuations are used. Before reaching of measurement zone of a channel liquid passes artificial vortex generator that induces strong disturbances in it. And when such fluctuation-vortex reaches magnetic field of measurement system we can observe a peak on its force-time characteristic while second system still measures stable flow. Then according to the time between peaks and the distance between measurement system observer can estimate mean velocity and, hence, flow rate of the liquid by equation:
  <div class="center"> <math>
  Q_{flow} = k \frac{D}{\tau}
  where  is the distance between magnet system,  the time delay between recorded peaks, and  is obtained experimentally for every specific liquid, as shown in figure 9.