Analysis and uncertainty quantification of a hybrid laminar flow control system

Abstract

This study aims at quantification of suction velocities for a hybrid laminar flow control (HLFC) application by taking data and model uncertainties into account. Since suction velocities cannot be measured directly, they are calculated using the Darcy-Forchheimer model. The model uses the pressure distribution and the porosity characteristics of the suction skin as boundary conditions that incorporate various sources of uncertainties. This paper attempts to quantify these uncertainties and to propagate them through the Darcy-Forchheimer model. The approach uses a sampling method to provide uncertainties associated with the suction velocities. In addition, the modelling error of the Darcy-Forchheimer model is estimated and also taken into account. It turns out that information on the local porosity characteristics of the suction skin is essential to reduce uncertainty of the estimated suction velocities for the application studied. In order to identify the most influential contributions to uncertainties of the suction velocities, a sensitivity study is carried out. The most influential contribution shows to be the uncertainty in the porosity characteristics, followed by uncertainties in the pressure distribution. Contributions with negligible influence are the model error and the uncertainty in reference pressure