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Over the past years, robust optimisations have become very popular and necessary. The aim of this type of optimisation is to consider the sensitivity of the output results to small variations in the operating conditions and manufa...
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Over the past years, robust optimisations have become very popular and necessary. The aim of this type of optimisation is to consider the sensitivity of the output results to small variations in the operating conditions and manufacturing tolerances. To study such sensitivities, an accurate and efficient method to quantify the uncertainties in physical processes is necessary. We present here the study and design of an S-duct, suitable for distributed propulsion configurations, and we address practical considerations of the application of robust optimisation to real-world design problems under multiple uncertainties. Two different non-intrusive Polynomial Chaos techniques have been chosen to quantify the input and output uncertainties, namely the non-intrusive point collocation and the non-intrusive spectral projection. These two techniques were implemented in two different robust optimisation problems (R1D and R2D) and their optima designs were analysed. To demonstrate the effectiveness of the robust optimisation problem formulation and analysis we compared the newly discovered optimum designs with previous non-robust optimum configurations. The results are discussed in detail and have shown a clear reduction in swirl values at the AIP, without affecting the pressure recovery of the diffuser when uncertainty properties were considered. In addition, robust codes have found S-duct shapes with swirl standard deviation values that are an order of magnitude smaller than the NON-Robust optimized designs and the baseline geometry.
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A methodology for the analysis and preliminary design of axial compressor rotors operating under clean and inlet flow distortion conditions is here discussed. An existing software based on a ID Mean-Line solver has been further de...
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A methodology for the analysis and preliminary design of axial compressor rotors operating under clean and inlet flow distortion conditions is here discussed. An existing software based on a ID Mean-Line solver has been further developed, enabling a quasi-2D discretization to deal with non-uniform inflows. Boundary conditions have been extracted from full-annulus CFD results through a novel procedure. A multi-objective optimizer has been implemented to activate the design mode. The application under clean and distortion conditions focuses on spanwise geometry optimization. Three-dimensional models have been rebuilt from ID results, and single-passage and full-annulus CFD simulations have been carried out for verification. The test cases considered are the transonic NASA Rotor 37, Rotor 67, and R4.
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摘要 :
A methodology for the analysis and preliminary design of axial compressor rotors operating under clean and inlet flow distortion conditions is here discussed. An existing software based on a ID Mean-Line solver has been further de...
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A methodology for the analysis and preliminary design of axial compressor rotors operating under clean and inlet flow distortion conditions is here discussed. An existing software based on a ID Mean-Line solver has been further developed, enabling a quasi-2D discretization to deal with non-uniform inflows. Boundary conditions have been extracted from full-annulus CFD results through a novel procedure. A multi-objective optimizer has been implemented to activate the design mode. The application under clean and distortion conditions focuses on spanwise geometry optimization. Three-dimensional models have been rebuilt from ID results, and single-passage and full-annulus CFD simulations have been carried out for verification. The test cases considered are the transonic NASA Rotor 37, Rotor 67, and R4.
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The present study proposes a robust optimisation strategy for the automatic shaping of inlet intakes in strong compressible conditions. Reynolds Averaged Navier-Stokes databases are mined inside Genetic Algorithms to generate opti...
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The present study proposes a robust optimisation strategy for the automatic shaping of inlet intakes in strong compressible conditions. Reynolds Averaged Navier-Stokes databases are mined inside Genetic Algorithms to generate optimal solutions concerning a priori defined goals. Based on an intake geometry available in literature, a validated steady-state model is used for multi-objective optimisation with the aim to reduce the drag coefficient while increasing the static and the total pressure ratios. The Pareto optimal solutions are analysed, looking at the flow patterns behaviour responsible for the improvements. Although the procedure is applied to a specific case, the method is entirely general, providing a smart flowchart for super/hypersonic intake design. In particular, since CFD data drive the optimisation, the process accounts for the whole complexities of such devices, including shock/boundary-layer interactions, recirculation bubbles and separate How portions from the earliest design stages.
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Industry is experiencing a new evolution phase where manufacturing is going through a process of digitalization, with every step of the production chain becoming smart. The emergence of IoT technologies and the fasted-paced evolut...
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Industry is experiencing a new evolution phase where manufacturing is going through a process of digitalization, with every step of the production chain becoming smart. The emergence of IoT technologies and the fasted-paced evolution in advanced computing capabilities enable a pervasive monitoring and rapid data processing, unleashing new applications, e.g., real-time error-correction and fault-detection, remote robot control, intelligent logistics. The flexibility and low cost of wireless solutions makes them appealing with respect to wired connections, but current wireless technologies operate at sub-6-GHz bands and are not able to meet the reliability, latency, and data rate demands of novel applications. In this paper, we give an overview of the main limits of current technologies and discuss the role that mmWaves may play in guaranteeing ultra reliable and low latency wireless communication in smart industry. We especially focus on the IEEE 802.11ad and 802.11ay standards for communication at 60 GHz. A factory work-cell is used as an illustrative example to explore the potential of mmWaves and how they could contribute to the realization of a resilient smart factory.
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The present paper describes the performance of URANOS, a high-fidelity Direct and Large-Eddy Simulation Navier-Stokes solver specifically developed for wall-bounded compressible flows. The code combines cutting-edge numerical meth...
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The present paper describes the performance of URANOS, a high-fidelity Direct and Large-Eddy Simulation Navier-Stokes solver specifically developed for wall-bounded compressible flows. The code combines cutting-edge numerical methods peculiarly developed for high-speed turbulent flow simulations and is tailored to modern high-performance computing systems due to MPI parallelization combined with multi-GPUs communication access. In particular, OpenACC directives are implemented for GPU enabling offloading computational loads onto accelerators cards, making URANOS an easily maintained solver as well as guaranteeing extreme flexibility and portability. The solver validation is detailed for a broad range of Mach numbers, from low-speed to compressible cases. In particular, velocity statistics and Reynolds stress components for canonical channel flow and turbulent boundary layer configurations obtained with URANOS well agree with high-quality DNS data. Computational performance and scaling properties are tested on several multi-GPU-equipped clusters. Thus, with URANOS, the scientific community can take advantage of a GPU-accelerated solver in dealing with fluid modeling for aerodynamics applications.
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Numerical simulations of a hypersonic ramjet intake at Mach 5 are performed combining a high-order and time-accurate Large-Eddy-Simulation model with a sharp-interface Immersed Boundary Method. The study aims at proving that advan...
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Numerical simulations of a hypersonic ramjet intake at Mach 5 are performed combining a high-order and time-accurate Large-Eddy-Simulation model with a sharp-interface Immersed Boundary Method. The study aims at proving that advanced fluid dynamics techniques, such as LES, in combination with an ad-hoc method for embedded geometries, represent a robust and accurate framework to deal with the unsteady and off-design behavior of highly-turbulent flows in the field of hypersonic applications. The authors show that the present methodology well reproduces the unsteady behavior observed in the experiment of Berto et al. in corresponding conditions, and allows a complete characterization of the 3D time-resolved flow fields.
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摘要 :
Numerical simulations of a hypersonic ramjet intake at Mach 5 are performed combining a high-order and time-accurate Large-Eddy-Simulation model with a sharp-interface Immersed Boundary Method. The study aims at proving that advan...
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Numerical simulations of a hypersonic ramjet intake at Mach 5 are performed combining a high-order and time-accurate Large-Eddy-Simulation model with a sharp-interface Immersed Boundary Method. The study aims at proving that advanced fluid dynamics techniques, such as LES, in combination with an ad-hoc method for embedded geometries, represent a robust and accurate framework to deal with the unsteady and off-design behavior of highly-turbulent flows in the field of hypersonic applications. The authors show that the present methodology well reproduces the unsteady behavior observed in the experiment of Berto et al. in corresponding conditions, and allows a complete characterization of the 3D time-resolved flow fields.
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