Application of a vortex shedding flowmeter to the wide range measurement of high temperature gas flow

A flowmeter for helium gas measurement in a Gas Cooled Fast Breeder Reactor loss of coolant simulation is described. A vortex shedding flowmeter was selected and specially modified to provide for a remoted thermal sensor. Experiments to determine the relationship between signal attenuation and sensor remoting geometry, as well as the relationship between gas flow parameters and remoted thermal sensor signal for both compressed air and helium gas were conducted, and the sensor remoting geometry optimized for this application. The associated temperature increase at the sensor position was 9 C above ambient (25 F) at a flowing temerature of 350 C. The volumetric flow accuracy was measured over the entire 155:1 flow range at parametric values of flowing density. A volumetric flow accuracy of + - percent of reading was demonstrated.