In this work the improved version of an engineering model which accounts for rotational augmentation effects by means of computational fluid dynamics(CFD)calibration is explored and discussed.Based on an analysis of t...In this work the improved version of an engineering model which accounts for rotational augmentation effects by means of computational fluid dynamics(CFD)calibration is explored and discussed.Based on an analysis of the NREL Phase VI wind turbine,the novel modeling is presented,which uses as base line the formulation proposed by Chaviaropoulos and Hansen.The model is calibrated based on CFD simulations using OpenFOAM.The corresponding correction of the two dimensional polars is straightforward implemented within MoWiT,an in-house software for load calculation.The novel formulation results in improved lift and drag coefficients prediction in all considered cases,reducing the deviation with respect to the rotating CFD cases down to few percent.The optimal configuration including the correction for tip effects of Shen shows better agreements at the very tip of the blade.Furthermore the range of applicability for large wind turbine rotor blades based on a virtual 10MW rotor model is discussed.展开更多
The study is focussing towards Metal Injection Moulding (MIM) of Mg-alloys for biomedical implantapplications. Especially the influence of the sintering processing necessary for the consolidation of thefinished part i...The study is focussing towards Metal Injection Moulding (MIM) of Mg-alloys for biomedical implantapplications. Especially the influence of the sintering processing necessary for the consolidation of thefinished part is in focus of this study. In doing so, the chosen high strength EZK400 Mg-alloy powdermaterial was sintered using different sintering support bottom plate materials to evaluate the possibilityof iron impurity pick up during sintering. It can be shown that iron pick up took place from the steelbottom plate into the specimen. Despite the fact that a separating boron nitrite (BN) barrier layer wasused and the Mg-Fe phase diagram is not predicting any significant solubility to each other. As a result ofthis study a new bottom plate material not harming the sintering and the biodegradation performance ofthe as sintered material, namely a carbon plate material, was found.展开更多
基金the German Ministry of Economy in the framework of HighRe National project(Grant O3EE2OO1)。
文摘In this work the improved version of an engineering model which accounts for rotational augmentation effects by means of computational fluid dynamics(CFD)calibration is explored and discussed.Based on an analysis of the NREL Phase VI wind turbine,the novel modeling is presented,which uses as base line the formulation proposed by Chaviaropoulos and Hansen.The model is calibrated based on CFD simulations using OpenFOAM.The corresponding correction of the two dimensional polars is straightforward implemented within MoWiT,an in-house software for load calculation.The novel formulation results in improved lift and drag coefficients prediction in all considered cases,reducing the deviation with respect to the rotating CFD cases down to few percent.The optimal configuration including the correction for tip effects of Shen shows better agreements at the very tip of the blade.Furthermore the range of applicability for large wind turbine rotor blades based on a virtual 10MW rotor model is discussed.
文摘The study is focussing towards Metal Injection Moulding (MIM) of Mg-alloys for biomedical implantapplications. Especially the influence of the sintering processing necessary for the consolidation of thefinished part is in focus of this study. In doing so, the chosen high strength EZK400 Mg-alloy powdermaterial was sintered using different sintering support bottom plate materials to evaluate the possibilityof iron impurity pick up during sintering. It can be shown that iron pick up took place from the steelbottom plate into the specimen. Despite the fact that a separating boron nitrite (BN) barrier layer wasused and the Mg-Fe phase diagram is not predicting any significant solubility to each other. As a result ofthis study a new bottom plate material not harming the sintering and the biodegradation performance ofthe as sintered material, namely a carbon plate material, was found.