Evaluation of the performance of dual chevron bluff body vortex flowmeters

Vortex flowmeters are less repeatable than turbine flow meters and the latter are normally preferred for high accuracy applications. One method of improving repeatability is to use two bluff bodies in series. Previous work has shown that certain combinations of two rectangular bluff bodies separated by a narrow gap give optimum repeatability. Features of using these bluff bodies suggest the use of chevron shaped bluff bodies. The results are presented of a wind tunnel evaluation of the vortex shedding performance of nine dual combinations based on six bluff body geometries for a range of separations between 3 and 15 mm.