Low temperature co-fired ceramic (LTCC)-based biosensor for continuous glucose monitoring

This article presents design, fabrication and testing of a miniature ceramic-based biosensor which is destined for continuous glucose monitoring. It is fabricated using well known LTCC (low temperature co-fired ceramics) technology. The biosensor consists of a microreaction chamber, three thick-film electrodes and a microdialysis tube. The detection process is based on oxidation of glucose by molecular oxygen in the presence of enzyme - glucose oxidase, GOx. One of the reaction products is a hydrogen peroxide which is detected amperometrically during its oxidation at a working electrode. Computational fluid dynamics (CFD) analysis was used for optimization of the biosensor geometry and considerations of the influence of operating conditions (flow rate) on mass transfer (diffusion) of the glucose within the microreaction chamber. Tests of the developed LTCC-based biosensor indicate its linear response to glucose concentration up to 9 mM with a relatively high sensitivity of about 147 nA/mM. Moreover, the properties of the presented ceramic biosensor are compared with properties of a similar device made in silicon/glass and in Perspex^®.     

微尺度射流流量计的设计与仿真研究

MEMS流量控制系统中,需要微型化的流量传感器,设计了一种反馈流驱动的微尺度射流流量计.采用数值模拟的方法对微尺度射流流量计进行研究,CFD软件的仿真结果表明:在较宽入口速度范围内该微尺度射流流量计起振快,振荡稳定,切换灵敏,斯特劳哈尔数基本恒定,并且流速测量下限可以达到0.075 m/s,在一定程度上为射流流量计的微...     

风机流场并行数值模拟在集群系统上的应用

介绍集群系统的特点及其软硬件配置环境。利用计算流体力学商用软件Fluent对一种新型垂直轴风力机风轮在曙光天潮超级服务器4000A集群上进行数值模拟及并行计算,得到风轮内外部的三维流场,实现该软件在高性能并行计算机上的应用,为并行有限元分析提供一个基础计算平台。     

SCR脱硝系统静态混合器优化布置数值模拟研究

基于CFD数值模拟技术系统地研究了静态混合器对改善SCR脱硝系统首层催化剂入口截面速度/浓度均匀分布特性的作用规律。数值计算结果表明,针对特定的静态混合器型式,优化前后速度/浓度分布偏差最大改善量分别为8.89%、12.26%,系统整体压损最大升高量约为188 Pa。因此认为静态混合器的优化布置可以显著改善截面内的速度/浓度均匀分布特性,但基于系统压损呈现的变化规律,建议在进行静态混合器设计时需综合权衡速度/浓度分布偏差改善性能与系统整体压损变化特性两方面的因素。     

基于CFD的摆线泵进出油腔对容积效率影响的分析

为提高摆线泵的容积效率,优化泵内部的流场分布,减少回流和空化现象.利用CFD方法对摆线泵内部流场进行数值模拟,定量分析月牙状进出油腔对泵容积效率的影响.仿真结果表明,适当减小G0并增大F0可以改善泵的内部流场分布,提高容积效率.仿真结果可以为摆线泵的结构设计提供参考.     

CFD方法在压水堆安全分析中的应用现状和发展趋势

为更好地利用CFD方法解决压水堆安全分析问题,简要介绍CFD方法,着重阐述其在硼稀释、混合和热分层以及受压热冲击等压水堆安全分析问题的应用现状,并提出CFD与系统程序的耦合计算、流固耦合计算和CFD与中子动力学程序的耦合计算将是CFD方法在该领域的发展重点.     

Computational performance of a parallelized three-dimensional high-order spectral element toolbox

In this paper, a comprehensive performance review of an MPI-based high-order three-dimensional spectral element method C++ toolbox is presented. The focus is put on the performance evaluation of several aspects with a particular emphasis on the parallel efficiency. The performance evaluation is analyzed with the help of a time prediction model based on a parameterization of the application and the hardware resources. Two tailor-made benchmark cases in computational fluid dynamics (CFD) are introduced and used to carry out this review, stressing the particular interest for clusters with up to thousands of cores. Some problems in the parallel implementation have been detected and corrected. The theoretical complexities with respect to the number of elements, to the polynomial degree, and to communication needs are correctly reproduced. It is concluded that this type of code has a nearly perfect speedup on machines with thousands of cores, and is ready to make the step to next-generation petaFLOP machines.     

Design optimization of an enzymatic assay in an electrokinetically-driven microfluidic device

Microfluidic systems are increasingly popular for rapid and cheap determinations of enzyme assays and other biochemical analysis. In this study reduced order models (ROM) were developed for the optimization of enzymatic assays performed in a microchip. The model enzyme assay used was β-galactosidase (β-Gal) that catalyzes the conversion of Resorufin β-d-galactopyranoside (RBG) to a fluorescent product as previously reported by Hadd et al. (Anal Chem 69(17): 3407–3412, 1997). The assay was implemented in a microfluidic device as a continuous flow system controlled electrokinetically and with a fluorescence detection device. The results from ROM agreed well with both computational fluid dynamic (CFD) simulations and experimental values. While the CFD model allowed for assessment of local transport phenomena, the CPU time was significantly reduced by the ROM approach. The operational parameters of the assay were optimized using the validated ROM to significantly reduce the amount of reagents consumed and the total biochip assay time. After optimization the analysis time would be reduced from 20 to 5.25 min which would also resulted in 50% reduction in reagent consumption.     

Experiences with Mathematical Modeling of Electro- Boost in Glass Furnaces

The goal of the latest strategy in glass companies is to decrease the cost of production while maintaining or increasing the glass quality. One of the perspective ways is to install the electric boosting into the existing furnace or to build the new furnace including the electric boosting. This strategy may be surprising as electric energy is generally more expensive than gas or oil （considering the cost per unit energy） but because of efficiency of use （ direct glass - melt heating by Joulean heat） it is inevitably cost effective. The use of the CFD modeling capability for electro - boost designing is presented in this contribution. The Glass Service Glass Furnace Model （ GS - GFM ） is used for investigating the optimal electrode arrangement and phasing, and moreover, for increasing the glass quality during the electro - boost applying.     

电磁流量计测量直管内速度及管长的CFD 研究

电磁流量计是一种广泛采用的流量测量仪表,测量直管长度对于保证测量管内流速轴对称分布及电磁流量计计量精度起着关键性作用.本文采用CFD数值手段对电磁流量计测量直管长度及管内流速轴对称分布特性展开研究.为了准确地研究流速分布的轴对称特性,提出了定量衡量流速分布轴对称程度的速度对称偏差度,并基于此研究了不同内径、不同过流量条件下测量管内的流速分布轴对称特性和电磁流量计对测量直管长度的要求,为电磁流量计的检定、安装、应用提供科学理论依据,为依托项目建立高精度流量计量标准装置奠定基础.