Xin Gong

Application of a Capacitance Solid Mass Flow Meter in a Dense Phase Pneumatic Conveying System of Pulverized Coal

Capacitance measurement is one of the available methods for measuring the solid mass flow rate in the field of gas‐solid flow. Performance of a capacitance solid mass flow meter was tested in a dense phase pneumatic conveying system of pulverized coal. Results have demonstrated that the deviations of mass flow rates in the experimental set‐up are almost within ±5% for stable flow patterns while unstable flow patterns and low conveying concentration pose great measurement deviations. On the other hand, the measurement accuracies in a vertical downward flow pipeline and a horizontal pipeline are almost identical and the both are slightly better man that in a vertical upward flow pipeline. Additionally, its performances in a pilot‐scale entrained‐flow gasification plant with dry feeding are also presented and satisfying results are achieved.

R/S method for unevenly sampled time series: Application to detecting long-term temporal dependence of droplets transiting through a fixed spatial point in gas–liquid two-phase turbulent jets

We perform rescaled range analysis upon the signals measure d by Dual Particle Dynamical Analyzer in gas-liquid two-phase turbulent jets. A novel re scaled range analysis is proposed to investigate these unevenly sampled signals. The Hurst ex ponents of velocity and other passive scalars in the bulk of spray are obtained to be 0.59 ±0.02 and the fractal dimension is hence 1.41 ± 0.02, which are in remarkable agreement with and much more pr ecise than previous results. These scaling exponents are found to be in dependent of the configuration and dimensions of the nozzle and the fluid flows. Therefore, su ch type of systems form a universality class with invariant scaling properties.

Inversion formula of multifractal energy dissipation in three-dimensional fully developed turbulence

The concept of inverse statistics in turbulence has attracted much attention in recent years. It is argued that the scaling exponents of the direct structure functions and the inverse structure functions satisfy an inversion formula. This proposition has already been verified by numerical data using the shell model. However, no direct evidence was reported for experimental three-dimensional turbulence. We propose to test the inversion formula using experimental data of three-dimensional fully developed turbulence by considering the energy dissipation rates instead of the usual efforts on the structure functions. The moments of the exit distances are shown to exhibit nice multifractality. The inversion formula between the direct and inverse exponents is then verified.