INVITRO STRESS MEASUREMENTS IN THE VICINITY OF 6 MECHANICAL AORTIC VALVES USING HOT-FILM ANEMOMETRY IN STEADY FLOW

Based on hot-film anemometry, point velocity measurements in the total cross sectional area 1 and 2 diameters downstream of Bjork-Shiley Standard, Convex-Concave and Monostut, Hall-Kaster (Medtronic-Hall), St. Jude Medical and Starr-Edwards Silastic Ball aortic vales were made. The spatial distribution of Reynolds Normal Stresses (RNS) was visualized three-dimensionally in order to point out where and to what extent the highest RNSs were found. The measurements were made in steady flowing glycerol mixture at flow rates 10, 20 and 30 1. min** minus **1 corresponding to mean velocities of 27, 54 and 81 cm s** minus **1. The highest maximum RNS values were around 250 Nm** minus **2 and were found downstream of the Bjork-Shiley Monostrut and Starr-Edwards Ball valves.