Preliminary studies employed an 8-inch (outlet diameter) contracting cone and an 8-inch converging nozzle. The design of the cone is based on an electromagnetic analogy reported by Smith and Wang, while the nozzle was designed assuming potential flow and using numerical methods to obtain the solution. Both designs yielded fairly uniform velocity fields, any deviations being primarily due to either construction or measurement techniques. The towing tank rating for a Pygmy current meter was compared with the submerged jet rating, the difference being 1 or 2 percent. A Prototype system was constructed using a 16-inch contracting cone (d). Two Type AA Price current meters were rated in this facility. The hydraulic performance of the system proved very satisfactory, illustrating that rating current meters in a submerged jet emanating from a contracting cone is feasible.
Skogerboe, Gaylord V.; Austin, Lloyd H.; Jeppson, Roland W.; and Wei, Chi-Yuan, "Feasibility of Rating Current Meters in a Velocity Field" (1968). Reports. Paper 91.