Effect Of Stream Turbulence Research Articles

Macrokinetic laws of polymerization of isobutylene in a tubular reactor

A method of simulating the process of cationic polymerization of isobutylene in a tubular reactor with distributed catalyst introduction has been developed. The effect of stream turbulence, the geometrical dimensions of the reactor, and the residence time on the monomer conversion is studied. Criteria for the jet conditions of polymerization and the completeness of utilization of the reaction space are obtained.

The effects of stream turbulence on separation bubbles

This paper describes experiments on the effects of stream turbulence on two-dimensional, separated and re-attaching flows. It is found that the mean flow-field responds strongly to turbulence intensity but with little effect of integral scale. Fluctuating pressures depend strongly upon both intensity and scale. Data correlations for fluctuating pressures are presented.

Erratum for “Effect of Stream Turbulence on Heater Water Plumes”

Erratum for “Effect of Stream Turbulence on Heater Water Plumes”

Erratum for “Effect of Stream Turbulence on Heater Water Plumes”

Erratum for “Effect of Stream Turbulence on Heater Water Plumes”

Effect of Stream Turbulence on Heater Water Plumes

The situation of a heated water surface jet flowing at the mean local velocity in open channel flow is studied. The jet contains no excess momentum that can cause mixing by relative motion of parallel streams. Downstream behavior is determined by buoyancy and ambient flow turbulence. Dimensional analysis determines the independent variables, \Ix/D\N, \Id/D\N, \Iu\N∗/\Iu\N\Dn\N, and \IF\N\Dd\N, which are a distance ratio, a depth ratio, a friction factor, and a densimetric Froude number. In the range of study axis temperature is observed to be independent of \Id/D\N and Froude number, and only weakly dependent on \Iu\N∗/\Iu\dN. Results are shown for temperatures versus \Ix/D\N. Mixing is significant, but dilution is less than for momentum jets in still water. Plume width due to buoy spread is shown to be (\Ix/D\N)\U2/3\N, to (\IF\N\Dd\N\N)\U-2/3\N (\Ix/D\N\U2/3\N, with increased widths measured for increased turbulence. Results for layer depth are shown vs. \Ix/D\N and are largely independent of \Id/D\N, \Iu\N∗/\Iu\N\Dn\N, and \IF\N\Dd\N.

Accuracy of Current Meter Measurements

Laboratory tests and field experience show that the probable accuracy of a stream flow measurement made by the usual current meter method is approximately 2%. This conclusion is based on a statistical analysis of the component errors of special measurements made on more than one hundred different streams, and on the results of other investigations reported in the literature. The errors considered are due to the rating of the meter, the effect of stream turbulence on the performance of the meter, the time fluctuation of velocity at a point, the assumption that the average of velocities taken at 0.2 and 0.8 depth equals the mean velocity, and the number of stations in the section at which observations are made. The standard deviation of each component error in percent of mean is evaluated from laboratory or field measurements. The individual variances are then combined to give the probable total error.