The Axial and Radial Solid Loadings up the CFB-Riser

1 INTRODUCTIONThe determination of the solids hold-up and local solidfluxes is of paramount importance in the study ofthe hydrodynamics of a two-phase flow.Several tech-niques have been used during the past decades(Table1).These methods can be classified in two groups,depending on their possible disturbance of the two-

Study on Radial Position of Impurity Ions in Core and Edge Plasma of LHD Using Space-Resolved EUV Spectrometer

Radial profiles of impurity ions of carbon, neon and iron were measured for high- temperature plasmas in large helical device （LHD） using a space-resolved extreme ultraviolet （EUV） spectrometer in the wavelength range of 60A to 400 A. The radial positions of the impurity ions obtained are compared with the local ionization energies, El of these impurity ions and the electron temperatures T,z there. The impurity ions with 0.3 keV 〈_ Ei ≤ 1.0 keV are always located in outer region of plasma, i.e., 0.7 ≤ p ≤ 1.0, and those with Ei ≤ 0.3 keV are located in the ergodic layer, i.e., 1.0 ≤ p≤ 1.1, with a sharp peak edge, where p is the normalized radial position. It is newly found that Tez is approximately equal to Ei for the impurity ions with Ei ≤ 0.3 keV, whereas roughly half the value of El for the impurity ions with 0.3 keV≤ Ei ≤ 1.0 keV. It is known that Tez is considerably lower than Ei in the plasma edge and approaches to Ei in the plasma core. Therefore, this result seems to originate from the difference in the transverse transport between the plasma edge at p 〈1.0 and the ergodic layer at p ≥ 1.0. The transverse transport is studied with an impurity transport simulation code. The result revealed that the difference appearing in the impurity radial positions can be qualitatively explained by the different values of diffusion coefficient, e.g., D=0.2 m2/s and 1.0 m2/s, which can be taken as a typical index of the transverse transport.

Study on Liquid-Phase Axial Dispersion in Converging Taper Liquid-Solid Fluidized Beds

It is found analytically that the parabolic radial profile of liquid velocity in cylindrical liquid-solid fluidized bed (LSFB) causes particles to circulate around some radial position. This is the main reason for liquid-phase axial dispersions. The liquid-phase axial dispersion is depressed as the liquid velocity presents a flatter Bessel radial profile in a converging taper LSFB. The void fraction increases with axial distance in converging taper LSFB. The behavior produces less liquid-phase axial dispersion. Experimental results show good coincidence.

Investigating Averaging Effect by Using Three Dimension Spectrum

The eddy current displacement sensor＇s averaging effect has been investigated in this paper, and the frequency spectrum property of the averaging effect was also deduced. It indicates that the averaging effect has no influences on measuring a rotor＇s rotating error, but it has visible influences on measuring the rotor＇s profile error. According to the frequency spectrum of the averaging effect, the actual sampling data can be adjusted reasonably, thus measuring precision is improved.

Statistics for Size and Radial Wind Profile of Tropical Cyclones in the Western North Pacific

The 6-yr best-track data of tropical cyclones （TCs） in the western North Pacific are used to study the statistical features of TC size and radial wind profile. A TC size is defined as the azimuthal mean radius of 34-kt surface wind. On average, the TCs in the western North Pacific have a size of 203 km, and the size is larger for stronger TCs. Further analyses show that larger TCs tend to move faster than smaller ones, with a 23–24 km difference in size corresponding to a difference of about 10 km h -1 in moving speed. The TCs that recurve from westward to eastward moving have a mean size of 218 km, significantly larger than that of those without a turning point （179 km）. Regional TC distributions demonstrate that the TCs affecting the Korean Peninsula and southwestern Japan have the largest mean size （250–280 km）. There are also some large TCs affecting southern Philippines, while TCs over the South China Sea are generally small in size. Comparison of intensity and size of all TCs during their lifespan demonstrates that a TC tends to reach its maximum size 6 h after it reaches its maximum intensity, and the decrease rate of size during the weakening stage of a TC is much smaller than the increase rate of size during its developing stage. Thus, linear regression relations between TC size and intensity are established for its developing and weakening stages respectively, which can be used as a forecast tool for TC size. Features of TC radial wind profile are studied by analyzing a parametric wind model based on the radius data of 34-, 50-, and 64-kt surface winds. The results show that the shape parameter d most frequently takes the values of 0.3, 0.4, and 0.5. It generally increases （decreases） as the TC develops （weakens）, implying a sharper （flatter） radial wind profile. Changes in d leads the tendency of intensity. The two parameters for the asymmetric model, namely p and q, are mostly 0.85–1.05 and 0–0.2, respectively, embodying the fact that the asymmetric component is generally much smaller than the symmetric component. The asymmetry in 34-kt surface wind is much stronger than that in 50and 64-kt surface winds, with the maximum radius often in the northeast quadrant.

Radial profile of bottom quarks in jets in high-energy nuclear collisions

Angular correlations between a heavy quark(HQ)and its tagged jet are potentially new tools to gain insight into the in-medium partonic interactions in relativistic heavy-ion collisions.In this work,we present the first theoretical study on the radial profiles of B mesons in jets in Pb+Pb collisions at the Large Hadron Collider(LHC).The initial production of a bottom quark tagged jet in p+p is computed by SHERPA,which matches the next-to-leading order matrix elements with contributions of parton showers,whereas the massive quark traversing the quark-gluon plasma is described by a Monte Carlo model,SHELL,which can simultaneously simulate light and heavy flavor in-medium energy loss within the framework of Langevin evolution.In p+p collisions,we find that at lower PQ/T the radial profiles of heavy flavors in jets are sensitive to the heavy quark mass.In 0-10%Pb+Pb collisions at√SNN=5.02 TeV,we observe an inverse modification pattern of the B meson radial profiles in jets at4PQ/T<20 GeV compared to those of D mesons:the jet quenching effects narrow the jet radial profiles of B mesons in jets while broadening those of D mesons in jets.We find that in A+A collisions,the contribution dissipated from the higher PQ/T>20 GeV region naturally has a narrower initial distribution and consequently leads to a narrower modification pattern of the radial profile;however the diffusion nature of the heavy flavor in-medium interactions will give rise to a broader modification pattern of the radial profile.These two effects consequently compete and offset with each other,and the b quarks in jets benefit more from the former and suffer less diffusion effect compared to that of c quarks in jets.These findings can be tested in the future experimental measurements at the LHC to gain better understanding of the mass effect of jet quenching.