Major accidents in the process industry often lead to the release of light or dense gases, which can mean a thread to employees, local residents or to the environment. Possible scenarios are therefore analyzed and evaluated in advance for approval issues. There is a trend, where simple empirical models are being replaced with more complex numerical models. Gaussian dispersion models or models based on dimensional analysis approaches are for example, increasingly replaced by CFD simulations. The main reason for this is the potentially higher accuracy. However, usually scenarios using sharp parameter values are calculated, since comprehensive consideration of parameter distributions via Monte Carlo or Latin Hypercube Sampling fails due to the numerical effort. This includes the risk that the influence of uncertainties on the simulation results is not taken into account. Response surface methods offer an alternative, with which the CFD problem can be mapped onto an algebraic surrogate model. If this is sufficiently precise, parameter sampling can also be carried out with the surrogate as well, as shown in some publications. Previous investigations only demonstrated the basic principle using trivial dispersion models. In this paper two realistic CFD simulations from the plant safety area are considered: VOC emissions from a storage tank and near-ground dense gas emissions. The entire procedure of response surface determination and parameter studies was automated and parallelized for high-performance-computing, and is carried out on the underlying CFD grids. For the CFD simulations as well as for all visualizations, the commercial software ANSYS CFX and the open source software OpenFOAM were used. The aim of this paper is to demonstrate the method using industry-relevant applications as well as to show how this can be used in practical engineering applications. The quality of surrogate modeling, the numerical effort and advantages that can result from the procedure are discussed as well as advantages which may result from taking parameter uncertainties into account in safety studies.

过程工业中的重大事故通常会导致释放轻质或浓密气体，这可能对员工、当地居民或环境造成影响。因此，会提前分析和评估可能出现的情况以解决审批问题。有一种趋势，简单的经验模型正在被更复杂的数值模型所取代。例如，高斯色散模型或基于维度分析方法的模型越来越多地被 CFD 模拟所取代。这样做的主要原因是潜在的更高的准确性。然而，通常会计算使用尖锐参数值的场景，因为通过蒙特卡罗或拉丁超立方采样对参数分布的综合考虑由于数值努力而失败。这包括未考虑不确定性对模拟结果的影响的风险。响应面方法提供了一种替代方法，通过它可以将 CFD 问题映射到代数代理模型上。如果这足够精确，也可以使用代理进行参数采样，如某些出版物中所示。以前的研究仅使用普通色散模型演示了基本原理。在本文中，考虑了工厂安全区域的两个真实 CFD 模拟：来自储罐的 VOC 排放和近地高密度气体排放。响应面确定和参数研究的整个过程是自动化和并行化的，以实现高性能计算，并在底层 CFD 网格上执行。对于 CFD 模拟以及所有可视化，使用了商业软件 ANSYS CFX 和开源软件 OpenFOAM。本文的目的是使用与行业相关的应用程序来演示该方法，并展示如何将其用于实际工程应用程序中。讨论了替代建模的质量、数值工作和程序可能产生的优势，以及在安全研究中考虑参数不确定性可能产生的优势。