OP-II-3

PP-I-2At the agitation of the liquid components in a pipe of the constant cross sectionthe pressure dropped owing to hydrostatic constituent and therefore the energy lossis characterized only by the pressure drop.THE INTENSITY OF THE AGITATIONUsually the intensity of the agitation is defined by time of reaching the giventechnological result or at the mechanical mixing by the speed of the agitator at a givenduration of the process. The agitation intensity is the higher the smaller is the time spentfor reaching of the given agitation result. The enhancing of the agitation results in thedecrease of the designing devices and in an output rise. It is required from the economicpoint of view that the target agitation is reached in the shortest time.A quantitative estimation of the agitation intensities of the direct flow agitators shouldbe related to the the given agitation result. The enhancing of the agitation results in thedecrease of the designing devices and in an output rise. It is required from the economicpoint of view that the target agitation is reached in the shortest time.A quantitative estimation of the agitation intensities of the direct flow agitatorsshould be related to the geometric size of the device. Thus in the pipe of round crosssection the agitation intensities can be described by a relation if the pipe diameter tothe length of the mixing device section.THE AGITATION EFFICIENCYThe agitation efficiency of the device expresses the quality of the mixingoperation.For estimation of the agitation efficiency in the general case a dispersion ofconcentration that is equaled to standard mean square deviation of concentrationfrom an average concentration should be determined [1]:12σ () t = ( C t Cср) dVV∫ ( ) − , (1)where the average concentration is calculated in accordance with:CсрV1=V∫VC dV . (2)For the direct flow agitators the efficiency of the mixing described by theconcentration dispersion in an area normal to the velocity vector after the mixingsection S:12σ ( x) = ( C Cср) dSS∫ − , (3)where the average concentration is calculated according to:CсрS1=S∫SC dS . (4)221