In this study, low-frequency-based numerical methods were used to predict the noise radiating from rotating horizontal axis wind turbine (HAWT) blades. The flow parameters in the vicinity of blade surfaces, which are ...
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In this study, low-frequency-based numerical methods were used to predict the noise radiating from rotating horizontal axis wind turbine (HAWT) blades. The flow parameters in the vicinity of blade surfaces, which are required for the Ffowcs Williams–Hawkings (FW–H) equation, were calculated using ANSYS FLUENT. The numerical model was verified against the experimental results from the National Renewable Energy Laboratory Phase VI wind turbine blades. The coupling analysis was integrated with four Reynolds-averaged Navier–Stokes turbulence models and FW–H equation under various boundary conditions. The standard k-Ε, SST k-ω and V2f turbulence models produced results in agreement with the available experimental pressure coefficient and relative velocity distribution data in the flow fields. Under the verification of aeroacoustic results, the SST k-ω turbulence model was more consistent with the large eddy simulation data. An Institute of Nuclear Energy Research 25-kW HAWT was employed to predict noise frequency distribution at nine points on the tower on the windward and leeward sides under different operating conditions. Noise frequency distributions on the windward and leeward sides exhibited slight differences, whereas those on the left and right sides of the tower were different because of wind-shear influence. Under operating conditions, the decibels of the low-frequency noise at 0–200 Hz were ∼25–40 dB, and the noise frequency distributions on the windward and leeward sides were similar. With increasing distance, the decibel number of the monitoring point ∼25 m away dropped to 0 dB. For the noise prediction in Case 2 (wind speed = 12 m/s, pitches = 18°), the decibel number at 50 m was ∼25 dB and was ∼15 dB at 70 m. In Case 3 (wind speed = 18 m/s, pitches = 33°), the decibel number at 50 m was ∼30 dB and was ∼20 dB at 70 m. The peak amplitude of the noise was inversely proportional to the increasing distance from the tower but proportional to the wind and rotation
作者:
Raut, YashasviChaudhri, Shiv Nath
Faculty of Engineering and Technology Department of Computer Science and Engineering Maharashtra India
Faculty of Engineering and Technology Department of Computer Science and Design Maharashtra India
Gas and biosensors are crucial in the modern healthcare system, enabling non-invasive monitoring and diagnosis of various medical conditions. These sensors are used in various applications, including smart home health...
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Existing deep learning-based point cloud denoising methods are generally trained in a supervised manner that requires clean data as ground-truth ***,in practice,it is not always feasible to obtain clean point *** this...
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Existing deep learning-based point cloud denoising methods are generally trained in a supervised manner that requires clean data as ground-truth ***,in practice,it is not always feasible to obtain clean point *** this paper,we introduce a novel unsupervised point cloud denoising method that eliminates the need to use clean point clouds as groundtruth labels during *** demonstrate that it is feasible for neural networks to only take noisy point clouds as input,and learn to approximate and restore their clean *** particular,we generate two noise levels for the original point clouds,requiring the second noise level to be twice the amount of the first noise *** this,we can deduce the relationship between the displacement information that recovers the clean surfaces across the two levels of noise,and thus learn the displacement of each noisy point in order to recover the corresponding clean *** experiments demonstrate that our method achieves outstanding denoising results across various datasets with synthetic and real-world noise,obtaining better performance than previous unsupervised methods and competitive performance to current supervised methods.
The aim of this research was to design and simulate a low-cost, easy-to-maintain molten aluminum alloy casting mechanism. This mechanism was intended to address labor shortages in harsh and high-temperature environmen...
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This paper proposes an event-triggered stochastic model predictive control for discrete-time linear time-invariant(LTI) systems under additive stochastic disturbances. It first constructs a probabilistic invariant set...
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This paper proposes an event-triggered stochastic model predictive control for discrete-time linear time-invariant(LTI) systems under additive stochastic disturbances. It first constructs a probabilistic invariant set and a probabilistic reachable set based on the priori knowledge of system *** with enhanced robust tubes, the chance constraints are then formulated into a deterministic form. To alleviate the online computational burden, a novel event-triggered stochastic model predictive control is developed, where the triggering condition is designed based on the past and future optimal trajectory tracking errors in order to achieve a good trade-off between system resource utilization and control performance. Two triggering parameters σ and γ are used to adjust the frequency of solving the optimization problem. The probabilistic feasibility and stability of the system under the event-triggered mechanism are also examined. Finally, numerical studies on the control of a heating, ventilation, and air conditioning(HVAC) system confirm the efficacy of the proposed control.
Climate change is a major issue all over the world which has a great impact on global warming especially in countries with hot arid climates like Egypt. With rapid urbanization, streets in Greater Cairo and new cities...
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Graph neural networks(GNNs)have gained traction and have been applied to various graph-based data analysis tasks due to their high ***,a major concern is their robustness,particularly when faced with graph data that h...
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Graph neural networks(GNNs)have gained traction and have been applied to various graph-based data analysis tasks due to their high ***,a major concern is their robustness,particularly when faced with graph data that has been deliberately or accidentally polluted with *** presents a challenge in learning robust GNNs under noisy *** address this issue,we propose a novel framework called Soft-GNN,which mitigates the influence of label noise by adapting the data utilized in *** approach employs a dynamic data utilization strategy that estimates adaptive weights based on prediction deviation,local deviation,and global *** better utilizing significant training samples and reducing the impact of label noise through dynamic data selection,GNNs are trained to be more *** evaluate the performance,robustness,generality,and complexity of our model on five real-world datasets,and our experimental results demonstrate the superiority of our approach over existing methods.
The effect of hydrogen and helium interaction,especially H-He ratio,on the irradiation behavior of nuclear materials has not yet been ***,this is an important basis for evaluating the irradiation properties of nuclear...
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The effect of hydrogen and helium interaction,especially H-He ratio,on the irradiation behavior of nuclear materials has not yet been ***,this is an important basis for evaluating the irradiation properties of nuclear materials and developing high irradiation resistant ***,30 keV H_(2)^(+)and He^(+)dual beams with four H-He ratios of 0:10,3:10,15:10,and 30:10 were used to irradiate the newly developed Fe9Cr1.5W0.4Si F/M steel in TEM to in-situ study the interaction and ratio effect of hydrogen and *** addition of H atoms significantly promoted the nucleation of dislocation loops and *** the early stage of irradiation,the average size and density of dislocation loops increased with the increase of H-He ***,the larger the H-He ratio,the easier it was to form a complex dislocation ***,the final saturation size of bubbles increased with the increase of H-He *** was first found that the swelling was affected by H concentrations,with high H concentrations slowing down the increase in *** a certain irradiation dose,a specific H-He ratio would lead to a swelling peak of Fe9Cr1.5W0.4Si F/M *** super-sized bubbles at grain boundaries(GBs)were found after H addition,resulting in a bigger swelling of GBs than the *** the swelling of the GBs and the matrix show a dependence on the H-He *** current work is of great significance for understanding the interaction between hydrogen and helium in nuclear materials.
作者:
Chaudhri, Shiv Nath
Faculty of Engineering & Technology Department of Computer Science and Design Wardha India
Organoid intelligence (OI), the next paradigm of intelligence, draws inspiration from the biological learning of organs. On the other hand, artificial intelligence (AI) draws its inspiration only from the cognitive pr...
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