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High-quality baijiu yeast – modified Sporidiobolus johnsonii A (MSJA) suffers from the problem of weak vitality, thus failing to combine high efficiency and high survival rate drying. Therefore, in this study, we firstly designed a real-time sampling experiment of MSJA spray drying process, and based on this, we established a New CFD model (N-CFD model) that can accurately simulate the variation of the spray drying process of microorganisms such as MSJA. Then, a new spray drying air inlet mechanism of "high-temperature cyclone in the center L-type guide plate + medium-temperature laminar flow in the peripheral holes and slots" was invented. Finally, the parametric scanning simulation was carried out to optimize the flow angle θ of the L-type guide plate using the N-CFD model. The results show that, firstly, the N-CFD model can accurately simulate the temperature distribution (P1 = 0.05) and the motion of drying particles in the drying tower. Secondly, the optimized new air inlet mechanism with the L-type guide plate flow angle θ = 47° can even out the temperature and particle distribution in the drying tower, which meets the "two-stage theory of spray drying." Finally, under the premise of ensuring the drying efficiency, the survival rate of MSJA spray drying was increased from 42.6% to 82.24%, which achieved the objectives of low sticking wall, high efficiency and high survival rate of spray drying MSJA. [ABSTRACT FROM AUTHOR]

Theoretical analysis and performance evaluation is of great significance to give guidance for engineers designing a better muffler cover of general purpose engine with higher success rate and less experiment trails. Therefore, in order to construct a accurate numerical prediction of muffler temperature analysis accounting for the effects of boundary conditions on temperature results calculation, CFD technology was adopted and the muffler cover of general purpose engines at three different starter states were chosen to carry out this research. Simulation results showed that the simulation results of muffler cover temperature increased with the increase of radiation emissivity and thermal status, and became more consistent with experimental values with the increase of prism layers. The temperature distributions and boundary radiosity distributions of muffler cover for different starter were basically the same. Average temperature of muffler cover was between 60 and70°C under three kinds of starter conditions, and the temperature distribution was reasonable, proving that the design of muffler cover was feasible.The temperature numerical results were basically consistent with the experimental results, and the relative error was within 10%, which indicated that prediction value can be reliable when all boundary conditions were set reasonably and physical-mathematical models was solved with right calculation methods. The research results in this paper can provide a theoretical basis for the early-design and developing of muffler cover for general purpose engine. [ABSTRACT FROM AUTHOR]

In order to meet the needs of customers and take advantage of the customer's innovative resources, companies open up their design activities of products to customers. In contrast to the traditional product innovation, the primary characteristic of open innovation is the participation of a large number of autonomous individuals across organisational boundaries, and there is not a central authority. Hence, it is necessary to study the dynamic mechanism for obtaining a good decision. This paper first studies the evolution of individual interaction based on game theory and then studies the dynamic characteristics of large-scale interaction. According to the results of simulation, it is concluded that the opinions are convergent under various communication conditions, and he convergent velocity distribution of the product solution with payoffs as the independent variable is obtained. A case study is used to deeply understand the participant behaviour based on the game theory and verify the conclusion of dynamic analysis in this paper. [ABSTRACT FROM AUTHOR]

Aiming at the problem of multilayer physical structure for the skeleton of porous media, a multiscale and multilayer structural model of heat and mass transfer processes for drying of grain packing porous media was established by applying the pore network method and multiscale theory. An experimental study on rice drying was conducted in order to validate this model. The simulation and experimental results indicated that the established model could explain the mechanical properties of rice drying well. The rate of heat transfer was faster than the rate of mass transfer and there was a higher moisture gradient inside the rice grain. The diffusion coefficient of rice embryo played an important role in the drying process, and whose effect on drying was larger than the diffusion coefficient of rice hull and chaff. The moisture was imprisoned effectively inside the rice when the diffusion coefficient of rice embryo was very small. [ABSTRACT FROM AUTHOR]

Cyclone separator, used as the biogas pretreatment equipment, was taken as the research object in this study. In order to improve the separation rate of biogas impurity particles, the influence of six different structural parameters of the cyclone separator on the particle separation rate was analyzed by a single factor control method. It was found that the gas inlet rectangular section size had significant influence on the particle separation rate, followed by the diameter of the gas outlet duct. However, the height of the cylinder and cone, the insertion depth of gas outlet duct, and the diameter of the down-comer tube had limited effects on the particle separation rate. The best improvement scheme was that the diameter of the gas outlet duct was 138 mm, and the gas inlet rectangular section was 130 × 56 mm2. The particle separation rate of 10 μm and above was greater than 98%, and the pressure drop at this time was 2.213 kPa. [ABSTRACT FROM AUTHOR]