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The secondary flow is a common phenomenon in fluid mechanics , The secondary flow theoretical and experimental research at home and abroad , with some success , and has applications in the aerospace, bio-engineering , water treatment , flood prevention , protection of the ecological environment , and membrane separation high technical areas, and more significant benefits . To this end, this paper two aspects of the secondary flow derived from experimental and theoretical depth study , the study include the following aspects : ⑴ centrifugal shear diameter Φ300 plexiglass material made ??of secondary flow to the entity model , using laser speedometer test model velocity distribution , analysis by data fitting within the model fills the entire stirred tank of the same four circular secondary flow . ⑵ to reproduce common secondary flow ( Dean Vortex , the derivation of the characteristic coefficient of the Taylor vortex , and Gete Le vortex ) . Then summarize relevant law , the introduction of a new variable in the energy equation Bernoulli equation the secondary flow energy hf concept derived based on the renunciation shear secondary flow coefficient (L) and secondary flow characteristics coefficient ( Z ) . ⑶ secondary flow centrifugal shear theory Coagulation ; comparing ordinary flow field and the centrifugal shearing effect of the secondary flow Coagulation ; experimental results show that : the centrifugal shear flow Coagulation floc cohesion faster floc more , large and dense particles settle quickly , the the coagulation effect 5 to 10 times the ordinary flow field . ⑷ use Similar to enlarge theory , use Froude guidelines and Renault guidelines , centrifugal shear flow field similar amplification amplified model coagulation reaction before similar results amplification .
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