Inverse determination of acoustic boundary conditions

该项目的目标是创建用于估计多孔材料声学边界条件的反数值波方法。这些反向估计方法的基本原理应得到发展和验证。项目目标分四个步骤实现：A)确定多孔吸收体模型参数的逆数值方法，b)描述用于混响室测量的参考吸收体的测量方法，c)将数值方法扩展到直接混响室测量，d)用于非局部反应吸收体，并且具有关于吸收体表面入射角分布的先验知识。定义和确定“代表性”角无关阻抗的方法的创建和验证。所应用的方法是结合数值方法和优化算法的测量技术。工程结果为声学计算方法提供了更为精确的输入数据，提高了预测的不确定性。

Goal of the project is the creation of inverse numerical wave methods for estimation of acoustic boundary conditions of porous materials. The fundamentals of these inverse estimation methods shall be developed and validated. The project goals are achieved in four steps: a) inverse numerical methods for determination of model parameters of porous absorbers, b) description of a measurement method for reference absorbers for reverberation chamber measurements, c) expansion of the numerical method towards direct reverberation room measurements, and d) for non-locally reacting absorbers and with a-priori knowledge about the distribution of incidence angles on the absorber surface, the creation and validation of a method for definition and determination of “representative” angular independent impedances. The methods applied are measurement techniques in conjunction with numerical methods and optimization algorithms. The results of the project are more precise input data for acoustic calculation methods, which gain improved prediction uncertainty.