Experiment And Theory Study On Multi-phase Circulating Exchanging Heat System

The flow characters of multiphase circulating exchanging heat system were studied experimentally and theoretically based on the experiment hydrodynamics, the modern measuring technology, the computational fluid dynamics and the nonlinear systems theory according as the chemical processes.Firstly, the multiphase circulating exchanging heat system which had some complex structures, different flow forms and factors was studied by some cold-state laboratory apparatus. The solid-liquid combined distributors which would be applied to the industry equipment were put forward based on the similarity and fluidization theory. Those kind of solid-liquid distributors were composed of a main distributor and a pre-distributor. The effect of the solid-liquid distributor was validated by means of experimental means. The flow style maps of the experiment circulating exchanging heat experiment system were protracted in different operational conditions. The rule of the total fluidized bed's pressure drop, the pressure drop of solid-liquid distributors, solid holdup and particle circulating rate in exchanging heat pipe were investigated in different operation conditions, physical quality and structure parameters. The main structural factors which would influence the solid holdup in the multiphase circulating exchanging heat system were confirmed. At the same time, the basic experimental data about the flow factors in different areas was measured in the normal conditions. Secondly, the industry multiphase circulating exchanger system was studied.Two sets of multiphase measuring systems were established. One was a multiphase flow image collection and disposal system Some difficult problems, such as image aberrance and the recognition of motion particles during the testing process, were resolved. The other was a photo electricity collection system which had measured the solid holdup in several pipes simultaneously. The relationship between the photo electricity signals and the signals of solid holdup was demarcated. The local resistance of main distributors in single flow and two phases were measured when the chamber was filed with pure water and was full of 30-40% solid holdup. At last, the main distributor designing formula which was verified by the pressure drop formula was introduced.Based on this, the districts flow status in chamber and exchanging heat pipe were instantaneous simulated in two-dimensional circulating exchanger system through the granule dynamical theory. The numerical simulation results were validated by...