Experiences with Flow-direction Instruments

The method of recording the direction of flows on the basis of the hydrodynamic zero-point measurement has now reached a certain limit, in spite of the good results achieved. While the available flow-direction devices are accurate enough for many purposes, they are all insufficient for perfectly exact prediction of the flow direction. The next problem will be to achieve a point-by point flow-direction record, whereby the test procedure must be simplified, accelerated, and the degree of accuracy of the test data improved.