Preparation of porous β-SiAlON ceramics using corn starch as pore-forming agent

Accurate and reliable measurement of key biological parameters during penicillin fermentation is of great significance for improving penicillin production. In this research context, a new hybrid soft sensor model method based on RF-IHHO-LSTM (random forest-improved​ Harris hawks optimization-long short-term memory) is proposed for penicillin fermentation processes. Firstly, random forest (RF) is used for feature selection of the auxiliary variables for penicillin. Next, improvements are made for the Harris hawks optimization (HHO) algorithm, including using elite opposition-based learning strategy (EOBL) in initialization to enhance the population diversity, and using golden sine algorithm (Gold-SA) in the search strategy to make the algorithm accelerate convergence. Then the long short-term memory (LSTM) network is constructed to build a soft sensor model of penicillin fermentation processes. Finally, the hybrid soft sensor model is used to the Pensim platform in simulation experimental research. The simulation test results show that the established soft sensor model, with high accuracy of measurement and good effect, can meet the actual requirements of engineering. 

An evolutionary deep learning soft sensor model based on random forest feature selection technique for penicillin fermentation process.

Multiobjective-clustering-based Optimal Heterogeneous Sensor Placement Method for Thermo-mechanical Load Identification

Due to their distinct textures, porous cellular materials have been of interest to many engineering applications. Energy conversion through such materials, especially at high temperatures, is governed by naturally coupled conduction-radiation physics. Therefore, a thorough understanding of the conduction-radiation behavior within these materials is important to properly design and optimize these materials. Several numerical methods developed over the last few decades allow to solve and study the influence of different textural parameters on coupled conductive-radiative heat transfers. These numerical methods require 3D digitized images of the sample of interest obtained either using 3D imagery technique or generated using numerical algorithms. To better represent the complex geometry, the 3D image of the sample requires high spatial resolution, and for a sample which is representative of involved physics might contain hundreds of millions of voxels which is complex to solve and computationally expensive. To cope with this issue, we developed a parallelized discrete scale numerical approach using cell centered Finite Volume Method (FVM) and deterministic ray tracing to solve coupled heat transfer within highly porous large scale complex cellular materials. At the heart of this method rests a decomposition approach based on modified zonal method which significantly reduces the coupling efforts, memory requirements, and computation time. The results of two test cases presented in this study are cross-verified with those presented in literature and computed using Star-CCM+ software. Finally, the method is applied to virtual fibrous sample. These results present the ability of the solver to consider different boundary conditions, at large temperature gradient across boundaries, and to deal with large samples consisting hundreds of million of voxels while providing accurate results. We also present and discuss the sensitivity of other associated parameters on the final results. 

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A modified zonal method to solve coupled conduction-radiation physics within highly porous large scale digitized cellular porous materials

Effects of three-dimensional pore structure on effective thermal conductivities of thermal insulation materials

Effect analysis of edge layers on volumetric radiative properties of nickel foams

Numerical investigations of the coupled conductive-radiative heat transfer in alumina ceramics

Improved Gold-SA algorithm for simultaneous estimation of temperature-dependent thermal conductivity and spectral radiative properties of semitransparent medium

Ch. Sun

Papers

Effect analysis of edge layers on volumetric radiative properties of nickel foams

Numerical investigations of the coupled conductive-radiative heat transfer in alumina ceramics

Improved Gold-SA algorithm for simultaneous estimation of temperature-dependent thermal conductivity and spectral radiative properties of semitransparent medium

Pore-level structural optimization of porous foams for enhancing heat transfer and reducing pressure drop simultaneously

Prediction of high-temperature infrared radiative properties of nickel foam ligaments