Development of a method to measure axial and radial dispersion coefficients in multiphase contactors with the volumetric flow modulation technique

过程工业中的接触器的任务是在不混相流体之间提供有效的质量和热量传递，以实现分离、富集或化学反应。对于接触器的工程设计，有必要了解接触器的主要水动力参数。其中包括气含率、气相速度和色散系数。该项目研究了一种新的、普遍适用的方法，通过最小体积流量调制和伽马辐射传输的相位同步测量来确定色散系数。目标是进一步发展该方法，分析该方法的基本不确定性，测试和评估不同的传感原理，对气泡柱装置进行全面研究，将该方法应用于滴流床反应器，并实施和测试该方法的扩展，通过射影伽马辐射透射测量获得径向色散系数。

Contactors in the process industry have the task to provide an efficient mass and heat transfer between immiscible fluids for the purpose of separation, enrichment or chemical reaction. For the engineering design of contactors, it is necessary to have the major hydrodynamic parameters. Among them are gas holdup, gas phase velocity and dispersion coefficients. The project deals with a new and universally applicable method to determine the dispersion coefficient via minimal modulation of a volumetric flow rate and phase-synchronous measurement of gamma radiation transmission. Objectives are to further develop this method, analyze fundamental uncertainties of the method, test and assess different sensing principles, provide a comprehensive study on bubble column devices, translate the method towards trickle bed reactors and implement and test an extension of the method to get also the radial dispersion coefficients via a projective gamma radiation transmission measurement.