[automatically translated] Have a simple instrument for measuring the water flow rate it is critical in the field of applications, especially when the measurement site is not be easily reached such as, for example, in the measuring stations of the solid and water erosion transport. The meter in cylinders, consisting of two half-cylinders with vertical axis which partially obstruct the liquid outflow, is a suitable instrument for this purpose. In memory is a report of the scale theoretical derivation of the flow meter in cylinders. In particular, the report proposed was originally Bernoulli equation applied between the upstream section of the instrument, where it measures the water depth, and that control is established where the critical state, in 'semi-modular assumed behavior of the meter. The report obtained is consistent with the approach used by Baiamonte and Iron (2007) based on analysis dimensional and incomplete autosimilitudine. The memory shows the comparison between the new flow rates of the scale and measures conducted by Baiamonte and Iron (2007) for different values of the throttling ratio, demonstrating that the control section does not coincide with the restricted section but, compared to this, it is moved downstream. So that an semi-modular behavior, in fact, the value of the width of the control section is always greater than the width of the narrow section and to an increasing extent with the upstream water depth and decreasing with the width of the narrow section. This behavior is justified by the fact that in the current restricted section loses linearity that regains only further downstream where it is to localize the control section. It is finally presented an empirical relationship for the estimation of the width of the control section as a function of water depth upstream and the width of the narrow section. This relationship allows to obtain, in closed form, the scale of the flow meter to the cylinder which fully reproduces the measurements from Baiamonte and Iron (2007).
|Number of pages||11|
|Publication status||Published - 2015|