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Powder mixers are used in many industries. In the present work, a new type of air swirling mixer was designed and optimized with eight horizontally arranged inlet pipes at the tangential inlet angle of 35°. The mixing of multi‐sized spherical particles (2.0, 3.0, 4.0, and 5.0 mm) was numerically investigated in the air swirling mixer by coupled computational fluid dynamics–discrete element method. The numerical results showed that multi‐sized particles achieved comparable mixing performance to monodisperse particles. The Lacey index for multi‐sized particles increased initially, and then reached a maximum value at 0.824. The upward velocity of the particles, vz, increased initially, and then decreased to zero along the bed height. The maximum value of vz occurred at a height of 40 mm. Particle radial velocity was larger near the wall than at the mixer tube centre area. The smallest particles aggregated in three layers. The collision number of the particles reached a maximum at bed height of 120 mm, which was consistent with the position of the maximum stress of the particles against the tube wall. [ABSTRACT FROM AUTHOR]

The drying characteristics of sludge in a uniaxial vacuum disc dryer are numerically studied in the present study, and the results showed that the drying process of sludge includes three stages: the viscous stage, the sticky stage, and the granular stage. The influence of main parameters such as sludge feeding rate, heat source temperature, and rotating speed of the shaft on the drying process of sludge in the uniaxial vacuum disc dryer is analyzed. In order to optimize the drying efficiency of the dryer, a differential push‐flow structure is proposed in this study, which provides different propulsion effects for the sludge in different drying stages. The differential push‐flow is achieved by changing the number and angle of the push‐flow blades on the discs. Compared with the dryer before optimization, the dryer with optimized differential push‐flow structure has better performance. [ABSTRACT FROM AUTHOR]

The genetic relationships between the stratigraphic textures, thickness changes, burial depths, and the characteristics of the geothermal zoning of the Cenozoic in the northwestern Shandong region were analyzed in this study. Methods involving segmented water temperature measurements of geothermal well drilling, wellhead hydrological surveys, geothermal reservoirs, and caprock thickness measurements and statistics were adopted. The following findings were revealed in this study's research results: (1) The Paleogene and Neogene reservoir types in the northwestern Shandong region were determined to be mainly water-bearing fine sandstone and medium-fine sandstone pores, with thick layered, interbedded, and zoned stratigraphic structures. The layered and zoned geothermal reservoirs were found to be primarily distributed in a zonal manner on the bedding plane and characterized by good regional continuity. The fine sandstone and medium-fine sandstone sections with well-developed pores and high water content levels were geothermal reservoirs, while mudstone sections were geothermal barriers. The reservoirs and barriers were characterized by interlayer structures; (2) The boundary between the sag basin and the uplifting was taken as the dividing line of the geothermal fields, and the geothermal areas in the northwestern Shandong region were divided into different geothermal fields, all belonging to the sedimentary basin's conductive geothermal resources; (3) The major geothermal reservoirs included the lower members of the Neogene Minghuazhen Formation, Guantao Formation, and Dongying Formation. The Quaternary argillaceous sediment and the mudstone in the upper member of the Minghuazhen Formation formed the caprocks in the study area. In this study, the macroscopic distribution laws of geothermal resources in the northwestern Shandong region were proposed and were considered to have practical significance for further exploration and development. [ABSTRACT FROM AUTHOR]

In order to research how to promote online shopping consumers’ application of after service, build an evolutionary game model of both consumers and e-stores. This paper introduces the variables of supervision and punishment, tries to introduce the smart contract as a powerful service guarantee, and analyzes the influence relationship of variables between the two players and their strategic choices. This paper analyzes the ESS of the system when the relationship among smart contract, revenue, supervision and punishment meets 8 different conditions. Finally, giving suggestions to optimize the after service in online shopping according to the results.

An analytical trajectory prediction method is put forward for skip re-entry of lifting vehicles. First, the 3-D analytical solutions of skip re-entry trajectory are developed, which are crucial to realize the analytical trajectory prediction. To facilitate the derivation, an auxiliary geocentric inertial frame is established to deal with the strong nonlinear problem caused by the Earth's rotation. Thereafter, the analytical solutions of the downrange, crossrange, and velocity are approximated by the outer solutions of a two-time scale singular perturbation. The analytical solutions of the altitude and flight-path angle are developed using regular perturbation techniques which can decompose the strongly coupled and nonlinear system into a sequence of linear problems. Second, since the analytical solutions are with respect to the lift-to-drag ratio and bank angle, a method based on the EKF technique is proposed to estimate the lift-to-drag ratio and bank angle of the re-entry vehicle. Third, the analytical trajectory prediction schemes for the lifting re-entry vehicle with multiple bank reversals are put forward. The simulations show that the proposed analytical solutions are in good agreement with the numerical solutions, but the computation time of the analytical solutions is about two orders of magnitude less than that of the numerical solutions. In addition, the superior performance of the proposed analytical trajectory prediction method is well demonstrated by the simulation results. [ABSTRACT FROM AUTHOR]