Impact Stresses in Flapper Valves - A Finite Element Analysis
نویسندگان
چکیده
Impact stresses in flapper valves have been calculated on the basis of a finite element analysis. The impact velocity at initial contact used in the present calculations, 8 m/s, has been taken £rom previous high speed photographic measurements. Our calculations indicate that the final impact velocity at oblique impact exceeds 8 m/s significantly. This "whip-lash effect" gives rise to higher impact stresses than those obtained at colinear impact. It is concluded that impact fatigue cannot be explained without taking oblique impacts into account. When an obliquity of 1° is co~sidered an impact stress of 730 N/mm (106 ksi) is attained.
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