Design and Characterization of a Novel Upward Flow Reactor for the Study of High-Temperature Thermal Reduction for Solar-Driven Processes
Design and Characterization of a Novel Upward Flow Reactor for the Study of High-Temperature Thermal Reduction for Solar-Driven Processes
复制标题
用于太阳能驱动过程高温热还原研究的新型上流式反应器的设计和表征
DOI：
10.1115/1.4037191
复制
发表时间：
2017
影响因子：
2.3
通讯作者：
P. Loutzenhiser
中科院分区：
文献类型：
--
作者：
H. Bush;Karl;R. Gill;S. Jeter;P. Loutzenhiser
介绍了真空下与高通量太阳模拟器（HFSS）耦合的上流式反应器（UFR）的设计和表征。UFR被设计为以超过50 K/s的加热速率通过集中照射将固体样品快速加热到高于1000 °C的温度。这样的条件是理想的检查高温热还原动力学的还原/氧化活性材料通过暂时监测O2演变。稳态，计算流体动力学（CFD）模型采用的设计，以尽量减少涡流和再循环的形成，和滞后和分散的特点，通过一套O2示踪实验，使用反卷积和连续搅拌釜式反应器（CSTR）的串联模型。将UFR的瞬态、CFD和传热模型与蒙特卡罗射线跟踪（MCRT）相结合，以确定HFSS样品上的辐射热通量，从而模拟空间和时间样品温度。模型化的温度进行了比较，在实验中，Co 3 O 4热还原为CoO和O2的样品内测量。床内的测量温度由实验持续时间内的平均顶部和底部模型化床温度限定。模型与实验温度的形状的小的差异是由于热电偶和床中的颗粒之间的接触电阻和光谱吸收率和发射率的变化，因为Co 3 O 4被减少到CoO和O2。
The design and characterization of an upward flow reactor (UFR) coupled to a high flux solar simulator (HFSS) under vacuum is presented. The UFR was designed to rapidly heat solid samples with concentrated irradiation to temperatures greater than 1000 °C at heating rates in excess of 50 K/s. Such conditions are ideal for examining high-temperature thermal reduction kinetics of reduction/oxidation-active materials by temporally monitoring O2evolution. A steady-state, computational fluid dynamics (CFD) model was employed in the design to minimize the formation of eddies and recirculation, and lag and dispersion were characterized through a suite of O2tracer experiments using deconvolution and the continuously stirred tank reactors (CSTR) in series models. A transient, CFD and heat transfer model of the UFR was combined with Monte Carlo ray tracing (MCRT) to determine radiative heat fluxes on the sample from the HFSS to model spatial and temporal sample temperatures. The modeled temperatures were compared with those measured within the sample during an experiment in which Co3O4was thermally reduced to CoO and O2. The measured temperatures within the bed were bounded by the average top and bottom modeled bed temperatures for the duration of the experiment. Small variances in the shape of the modeled versus experimental temperatures were due to contact resistance between the thermocouple and particles in the bed and changes in the spectral absorptivity and emissivity as the Co3O4was reduced to CoO and O2.