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This paper mainly focuses on the problems of inaccurate measurement of the primary air flow rate in a coal-fired power plant. The feasibility of improving the uniformity of flow fields and temperature fields by installing double-layer arch cool air distributor and mixed flow matrix was analyzed by the method of numerical simulation. The results show that, the relative standard deviation of the wind speed measurement section of optimization model decreased from 18.7%~18.4% to 9%~9.1%, compared with the original model. Similarly, the relative standard deviation of temperature measurement section also decreased from 15%~14.6% to 1.3%~1.4%. The study suggests that this mixed flow fields equalization solution can effectively enhance the mixing of cool and hot primary air, and can improve the uniformity of the mixed air flow fields, thereby improving the accuracy and reliability of primary air measurement.

The rational creation of two-component conjugated polymer systems with high levels of phase purity in each component is challenging but crucial for realizing printed soft-matter electronics. Here, we report a mixed-flow microfluidic printing (MFMP) approach for two-component π -polymer systems that significantly elevates phase purity in bulk-heterojunction solar cells and thin-film transistors. MFMP integrates laminar and extensional flows using a specially microstructured shear blade, designed with fluid flow simulation tools to tune the flow patterns and induce shear, stretch, and pushout effects. This optimizes polymer conformation and semiconducting blend order as assessed by atomic force microscopy (AFM), transmission electron microscopy (TEM), grazing incidence wide-angle X-ray scattering (GIWAXS), resonant soft X-ray scattering (R-SoXS), photovoltaic response, and field effect mobility. For printed all-polymer (poly[(5,6-difluoro-2-octyl-2H-benzotriazole-4,7-diyl)-2,5-thiophenediyl[4,8-bis[5-(2-hexyldecyl)-2-thienyl]benzo[1,2-b:4,5-b′]dithiophene-2,6-diyl]-2,5-thiophenediyl]) [J51]:(poly[N,N′-bis(2-octyldodecyl)naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5′-(2,2′-bithiophene)) [N2200]) solar cells, this approach enhances short-circuit currents and fill factors, with power conversion efficiency increasing from 5.20% for conventional blade coating to 7.80% for MFMP. Moreover, the performance of mixed polymer ambipolar [poly(3-hexylthiophene-2,5-diyl) (P3HT):N2200] and semiconducting:insulating polymer unipolar (N2200:polystyrene) transistors is similarly enhanced, underscoring versatility for two-component π -polymer systems. Mixed-flow designs offer modalities for achieving high-performance organic optoelectronics via innovative printing methodologies.

Tip clearance between blade end and shroud is inevitable in pump operation and of great importance on pump energy performance and pressure fluctuation. As the tip clearance size increases, the head and efficiency of the mixed flow pump drop accordingly. The simulation results show that the development of a leakage vortex is observed as the tip clearance increases, and the trajectory of this leakage vortex remains in the same direction along the blade suction side for different tip clearances. With the increase in tip clearance size, the intensity of the leakage vortex is enhanced, and the separation between the main leakage vortex and the secondary leakage vortex is also strengthened. The leakage separation angle near the blade tip remains at the same value of 10° for different tip clearance sizes. As for the spectrum analysis, the maximum amplitudes of pressure fluctuations dramatically increase in the impeller when the tip clearance increases from 0.0 mm to 1.0 mm, and the dominant frequencies go from 145 Hz to 184 Hz due to the considerable leakage flow.

In mixed‐flow assembly lines, conflicts exist between the diverse production modes and the dynamic maintenance demand. There is an urgent demand to shift the adaptive manufacturing from passive scheduling to proactive scheduling. The uncertain evolution of the scheduling performance and the equipment state causes difficulty in balancing the production load and the predicted maintenance under the degradation effect. This paper aims at the production scheduling and mixed‐flow assembly line maintenance and proposes an improved hybrid Tabu Search and Genetic Algorithm (hybrid TSGA)–based proactive scheduling method for production prediction. Initially, the method constructs a real‐time state model for the equipment state, workshop manufacturing efficiency, manufacturing resource state, and manufacturing execution system feedback information. The production process status information is used as input to a mathematical modeling method, which is used to obtain the production trend of mixed flow assembly line in the workshop. Afterward, the hybrid TSGA is deployed and its sequential decision‐making capability is used to generate a proactive scheduling scheme based on the production trend prediction. The proposed methodology was implemented in a robotic flexible welding automobile production line for production scheduling, with its efficacy empirically validated. Simulation results demonstrated a 6% reduction in total completion time for multimachine, multiprocess scheduling scenarios, demonstrating superior performance.

This study designed a corn kernel drying device and optimized the structure of key components. FLUENT software was used for numerical simulation of wet heat coupling. The differences in physical fields were compared within the drying section before and after optimization. The optimized drying section exhibited improved drying uniformity, drying efficiency, and drying quality. The optimized drying section took 180 seconds for the temperature at the center point to reach the expected value, while the mixed flow drying section took 240 seconds. The moisture content of the optimized drying section decreased to 3.79% at this point, while that of the mixed flow drying section was 2.89%. The results indicated that the drying uniformity and efficiency of the optimized drying structure were higher than those of the mixed flow drying structure. This research provides important data for the design of corn drying equipment.

The stability and functionality of urban drainage networks are critical for flood mitigation. Transient mixed flows frequently arise during intense rainfall events or abrupt operational disturbances, generating substantial pressure surges that threaten pipeline integrity. In this study, an integrated experimental–numerical approach was employed to systematically investigate the transient behaviour of mixed flows. A transparent pipe system, 20 m in length and 0.15 m in diameter, was developed to examine three representative scenarios: sudden upstream inflow surge with free outflow, sudden upstream inflow surge with submerged outflow, and sudden downstream closure under steady inflow. To capture short-lived air compression and interface evolution rarely reported in previous studies, synchronous pressure measurements at both the pipe crown and invert were combined with high-speed visualisation. On the numerical side, an one-dimensional hybrid Random Choice Method–Godunov-Type Scheme model was developed. The model incorporates an adaptive switching strategy, applying Godunov-Type Scheme in smooth regions and Random Choice Method in zones of strong discontinuity. To prevent spurious switching and ensure numerical stability, a dual-threshold switching criterion was introduced. The proposed hybrid model enables stable resolution of sharp hydraulic discontinuities while limiting numerical errors in smooth regions during rapid flow regime transitions. Furthermore, comparison with experimentally observed surge front propagation and pressure evolution under various boundary conditions shows that the model reproduces the measured results with deviations within 5%. These results demonstrate that the proposed framework is robust and reliable, providing a validated and practical tool for simulating transient mixed flows in urban drainage systems.

Mixed‐flow pump is a typical pump using in low‐head cases of water lifting. The flow field pulsation is usually an important issue in the operation of mixed‐flow pumps and their pumping statins. Due to its large size, it is difficult to monitor the internal flow characteristics well, based on computational fluid dynamics, we use 5678 monitoring points which arranged in the impeller and fixed vane with using the high pulsation tracking network, and the pressure pulsation signals are analyzed by fast Fourier transform and variable mode decomposition to decompose the main frequency and intensity of the pressure pulsation signals, then analyze the energy dissipation with the entropy production rate (EPR). It is found that there are strong low‐frequency (0.416, 0.625, and 1.67 Hz) pressure pulsation near hub, and the pressure pulsation on the shroud is stronger than that on the hub (at least three times or more); there are strong and stable pressure pulsation (25 Hz) on the shroud generated by the rotor–stator interference (RSI); and the EPR in the flow field can be well combined with the signal. Reasonably allocating material strength and controlling the number of vanes and impellers to avoid producing a common multiple can avoid pressure pulsation caused by RSI and reduce energy dissipation. Therefore, it is very effective in improving the efficiency of this part. Under low flow conditions, the siphon outflow passage can predict the high‐frequency (45.833 Hz) attenuation area well through the phase signal decomposition of the signal, which has certain significance for improving its stability and efficiency. This article uses pulsation tracking network (PTN) to track the four interfaces of the simulation model of a vertical guide vane mixed flow pump, perform VMD decomposition on pressure pulsation data and analyze the distribution pattern of pressure pulsation. Understand the variation law of dynamic and static interference between the number of impellers and the number of guide vanes, analyze the relationship between the main frequency, phase, and energy dissipation of a siphon type outflow channel. Achieved analysis of temporal, spatial and frequency, and investigated the intricate flow within a mixed‐flow pump unit within a quasi‐three‐dimensional spatial system.

The rational creation of two-component conjugated polymer systems with high levels of phase purity in each component is challenging but crucial for realizing printed soft-matter electronics. Here, we report a mixed-flow microfluidic printing (MFMP) approach for two-component π-polymer systems that significantly elevates phase purity in bulk-heterojunction solar cells and thinfilm transistors. MFMP integrates laminar and extensional flows using a specially microstructured shear blade, designed with fluid flow simulation tools to tune the flow patterns and induce shear, stretch, and pushout effects. This optimizes polymer conformation and semi-conducting blend order as assessed by atomic force microscopy (AFM), transmission electron microscopy (TEM), grazing incidence wide-angle X-ray scattering (GIWAXS), resonant soft X-ray scattering (R-SoXS), photovoltaic response, and field effect mobility. For printed all-polymer (poly[(5,6-difluoro-2-octyl-2H-benzotriazole-4,7-diyl)-2,5-thiophenediyl[ 4,8-bis[5-(2-hexyldecyl)-2-thienyl]benzo[1,2-b:4,5-b′]dithiophene-2,6-diyl]-2,5-thiophenediyl]) [J51]:(poly{[N,N′-bis(2-octyldodecyl) naphthalene-1,4,5,8-bis(dicarboximide)-2,6-diyl]-alt-5,5′-(2,2′-bithiophene)}) [N2200]) solar cells, this approach enhances short-circuit currents and fill factors,with power conversion efficiency increasing from 5.20% for conventional blade coating to 7.80% for MFMP. Moreover, the performance of mixed polymer ambipolar [poly(3-hexylthiophene-2,5-diyl) (P3HT):N2200] and semiconducting:insulating polymer unipolar (N2200:polystyrene) transistors is similarly enhanced, underscoring versatility for two-component π-polymer systems. Mixed-flow designs offer modalities for achieving high-performance organic optoelectronics via innovative printing methodologies.

It is significant to explore the slip velocity characteristics of two-phase in blade tip clearance (BTC) of multiphase pump for improving semi-open mixed-flow pump performance. On the ground of the Euler-Euler inhomogeneous model, a gas-liquid mixed-flow pump was taken as the research object. Using CFX software to simulate the flow field in the multiphase pump with conditions of the inlet gas void fraction (IGVF) are 10%, 20% and 30%. The slip velocity characteristics of gas-liquid two-phase in mixed-flow multiphase pump with different blade tip clearance sizes (BTCS) were analyzed. The results show that there is obvious slip velocity on blade leading edge (L.E.), trailing edge (T.E.) and pressure side (PS) of BTC of mixed-flow pump impeller. When BTCS is small, the slip velocity on the tip pressure side has little change along flow direction, but with the increase of BTCS, slip velocity on the tip pressure side will gradually increase. There is a positive correlation between slip velocity and the pressure gradient. The research results can provide significant guidance for optimization design of semi-open mixed-flow multiphase pump.

For the inverse designs of centrifugal and mixed-flow pump impellers, clarifying the generation process of secondary flows and putting forward corresponding suppression measures is an important approach to improve the impeller performance. In this paper, to provide a better qualitative insight into the generation mechanism of secondary flows in the impeller, a simple kinematic equation is derived based on the ideal assumptions, which indicates that the potential rothalpy gradient (PRG) is the most important dynamic source that actively induces secondary vortical flows. Induced by the natural adverse PRG on the S1 and S2 stream surfaces, two typical secondary flows, H-S and P-S secondary flows, are clearly presented. To specially suppress these typical secondary flows, a general alternate loading technique (GALT) is proposed, aiming to adjust the real blade loading δp to control the PRG features. At the blade fore part, the δp on the hub streamline should be slowly increased to avoid breakneck growth of the potential rothalpy to reduce adverse streamwise PRG on the S2 streamsurface. At the blade middle part, the δp should be moderately decreased to reduce adverse streamwise PRG on the S1 streamsurface. At the blade aft part, the difference in the δp between the shroud and hub streamlines should be decreased faster to control the exit uniformity. By applying the GALT to the impeller designs of three typical pump types in hydraulic engineering, the organizational effect of the PRG on fundamental flow structures is proven. The GALT can effectively control the PRG distributions and suppress the secondary flows, thereby widening the pump’s high-efficiency zone, improving flow uniformity and suppressing pressure fluctuations. Compared with the current Z-G method and the ALT, the GALT can meet the requirements of “de-experience” better, thereby enabling the designers to obtain good products explicitly and quickly.