Governing variable and its experimental measurement

If Re was kept constant in scaling-up, a very small impinging velocity u() would be employed for a large system with a large diameter drawing tube da. On the other hand, the kinetic energy for the impingement is supplied by the streams, which are positively 

In view of the extreme importance of the impinging velocity, n(), in the implementation of impinging stream technology, in all the investigations worked by the author of this book u0 is employed as the governing variable, as was done in the chapter on absorption. 

Since the drawing tube in the experimental reactor is very short, the measurement of the velocity in the tube, i.e., the impinging velocity un, is very difficult. Xiao [13] 

Because the moving velocity of the recording paper is constant, the lag time can be determined according to the length the paper travels up to the instant the response just emerges, L, provided that the instant the tracer was inputted, tih was exactly labeled. Then the mean velocity can be calculated by 

An important piece of information that can be obtained from the measurement is that the impinging velocity is very small under normal conditions of SCISR operation, only of the order of magnitude of 10 1 m-s-1, implying very low power consumption, although the SCISR gives an excellent performance of promoting micromixing efficiently. 

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