Abstract The goal of the work is to determine unknown parameters of reactor heating in the process of biomass solar pyrolysis. The lab-scale reactor is heated by a xenon lamp, but the fraction of heat absorbed by the reactor is unknown, as well as the heat transfer coefficient from the reactor walls to the nitrogen flowing through internal reactor channels, and the overall heat transfer coefficient through the external reactor walls to the surroundings. The missing parameters are impossible to measure, therefore they need to be determined by solving the inverse problem. As the problem is strongly ill-conditioned, since the quantities are directly dependent on each other, two different inverse algorithms were used to retrieve them, namely, the Levenberg-Marquardt method and the Metropolis-Hastings method. The effectiveness of both methods was assessed and then they were applied to the real data. The inverse problem has been implemented in the MatLab software, while validation of the mathematical model and optimisation procedure was carried out with a CFD model built in Ansys Fluent 19.2. Calculations have shown that 14.4% of the lamp power penetrates inside the reactor and heat transfer coefficients to the flowing nitrogen equals 8.74 W/m2K and 0.965 W/m2K to the surroundings.

中文翻译：

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逆方法在生物质太阳能热解数学模型未知参数估计中的应用

摘要 本工作的目的是确定生物质太阳能热解过程中反应器加热的未知参数。实验室规模的反应器由氙灯加热，但反应器吸收的热量比例未知，以及从反应器壁到流经反应器内部通道的氮气的传热系数和总传热系数通过外部反应器壁到达周围环境。缺失的参数无法测量，因此需要通过求解逆问题来确定。由于问题是强病态的，由于数量直接相互依赖，因此使用了两种不同的逆算法来检索它们，即 Levenberg-Marquardt 方法和 Metropolis-Hastings 方法。评估了两种方法的有效性，然后将它们应用于实际数据。反问题已在 MatLab 软件中实现，同时使用 Ansys Fluent 19.2 中构建的 CFD 模型对数学模型和优化程序进行验证。计算表明，14.4% 的灯功率穿透反应器内部，流动的氮气的传热系数为 8.74 W/m2K，与周围环境的传热系数为 0.965 W/m2K。