A precursor in waterhammer analysis – rediscovering
نویسندگان
چکیده
In 1883 Johannes von Kries published the theory of waterhammer in a study of blood flow in arteries. He derived the “Joukowsky formula” before Joukowsky (1898) and Frizell (1898) did. He considered skin friction in unsteady laminar flow and thus derived formulas for wave attenuation and line pack. The theory was confirmed by experimental results obtained in rubber hoses. In 1892 he published the first textbook describing “classical” waterhammer. It presents formulas for phase-velocity and damping that are frequency-dependent because of skin friction, and in this sense it is the first contribution to the – these days popular – subject of unsteady friction.
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