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Research on Bionic Airfoil Design Method Based on Re-Evolution Optimization and Multi Objective Application on Horizontal Axis Wind Turbines

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SSRN 2023年

作者： Huang, ShengXian Yan, Hua Qiu, HuiHe Wang, Ying Shanghai Key Laboratory of Multiphase Flow and Heat Transfer of Power Engineering School of Energy and Power Engineering University of Shanghai for Science and Technology Shanghai China Department of Mechanical and Aerospace Engineering The Hong Kong University of Science and Technology Clear Water Bay Hong Kong

The design of specific airfoil for wind turbine is a crucial factor in the research of wind turbine performance and stability. Based on bionic methods and numerical optimization methods, a brand new airfoil design method is proposed without relying on any traditional airfoil and airfoil design experience. This study proposes a re-evolution method (numerical optimization methods) suitable for designing bionic airfoils based on the previously proposed bionic airfoil (Dol-Rot24°), which was inspired by the Dall's Porpoise. According to this method, a new airfoil is successful designed that gives consideration to both aerodynamic performance and roughness sensitivity. The research content mainly focuses on two aspects: new airfoil design and the new airfoil performance verification. In terms of the new airfoil design, a surrogate model based on radial basic function (RBF) is established for predicting aerodynamic performance and roughness sensitivity of airfoils. This surrogate model can significantly reduce the cost of bionic airfoil optimization calculations, and control the time of 8000 optimization iterations within 1 minute. Based on the actual engineering environment of a horizontal axis wind turbine, the multi-island genetic algorithm is used to adjust the profile of the Dol-Rot 24° airfoil. The optimized airfoil is named Dol-Rot 24° opt. In the performance verification of the Dol Rot 24° opt airfoil, it is found that compared with the Dol Rot 24° airfoil, the lift coefficient of the Dol Rot 24° opt airfoil is increased by 171.06%, and the lift-to-drag ratio is increased by 52.41% at most. Moreover, the roughness sensitivity of the Dol-Rot 24° opt airfoil is also the best among the three airfoils (S809, Dol-Rot 24°, Dol-Rot 24° opt). By modeling the three airfoils according to the NREL Phase VI wind turbine blade parameters and conducting numerical simulations, it is found that the newly optimized wind turbine blades exhibit greatly improved energy efficiency. Th

关键词： Airfoils

Research on Bionic Airfoil Design Method Based on Re-Evolution Optimization and Multi Objective Application on Horizontal Axis Wind Turbines

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SSRN 2023年

作者： Huang, Shengxian Yan, Hua Qiu, Huihe Wang, Ying Shanghai Key Laboratory of Multiphase Flow and Heat Transfer of Power Engineering School of Energy and Power Engineering University of Shanghai for Science and Technology Shanghai China Department of Mechanical and Aerospace Engineering The Hong Kong University of Science and Technology Clear Water Bay Hong Kong

The design of specific airfoil for wind turbine is a crucial factor in the research of wind turbine performance and stability. Based on biomimetic methods and numerical optimization methods, a brand new airfoil design method is proposed without relying on any traditional airfoil and airfoil design experience. A new airfoil is successful designed that gives consideration to both aerodynamic performance and roughness sensitivity. Based on the actual engineering environment of a horizontal axis wind turbine, the multi-island genetic algorithm is used to adjust the profile of the biomimetic airfoil (Dol-Rot24°). The optimized airfoil is named as Dol-Opt. In the performance verification of the Dol-Opt airfoil, it is found that compared with the Dol-Rot24°, the lift coefficient of the Dol-Opt airfoil is increased by 171.06%, and the lift-to-drag ratio is increased by 52.41% at most. Moreover, the roughness sensitivity of the Dol-Opt is also the optimum among the three airfoils (S809, Dol-Rot 24°, Dol-Opt). By conducting numerical simulations, it is found that the newly optimized wind turbine blades exhibit greatly improved energy efficiency. The purpose of this study is to provide effective references for the design, bionic methods, and practical engineering applications of wind turbine specific airfoils. © 2023, The Authors. All rights reserved.

关键词： Airfoils

Pirani gauge based hermeticity monitoring for un-cooled micro bolometer array

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Pirani gauge based hermeticity monitoring for un-cooled micr...

2009 16th IEEE International Symposium on the Physical and Failure Analysis of Integrated Circuits, IPFA 2009

作者： Tao, Dong Bin, Xiao Anders, Elfving Zhaochu, Yang Nhut, Tran-Minh Einar, Halvorsen Nils, Høivik Norwegian Center of Expertise on Micro- and Nanotechnology Vestfold University College I.M.S.T./R.I. Tønsberg Norway SensoNor AS Knudsrødveien 7 N-3192 Horten Norway State Key Lab of Multiphase Flow in Power Engineering Xi'an Jiaotong University Xi'an China

ISBN: (纸本)9781424439102

This paper presents a novel method to analyze the thermal conductance under vacuum environment for MEMS devices. The Si/Ge-based Pirani gauge introduced is developed for monitoring the package hermeticity of MEMS Bolometer array, which has the total same structure as the single bolometer pixel for the characteristic of functional material. Meanwhile the 'Extended Fourier's Law' is verified by free molecular theory and is applied into the thermal analysis of the micro-structure under the pressure below 100Pa. Thermal interaction between Focus Plane Arrays (FPAs) and Pirani gauge is checked to guarantee the normal performance as the influence from each side are under 2X lO-3K, which is acceptable for the products. This design can save the cost in fabrication significantly due to no extra process flow. The commercial value is affirmed by industry partner. ©2009 IEEE.

关键词： Bolometers

Analysis of Different Control Strategies Considering Individual Regulation of Heat User

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Analysis of Different Control Strategies Considering Individ...

Electrical engineering and Mechatronics Technology (ICEEMT), IEEE International Conference on

作者： Zhiwei Xun Huijie Wang Liyuan Wang Long Yang Yunfang Gao Ming Liu Guoneng Jinjie Energy Co. Ltd Yulin China Xi’an Jiaotong University Xi’an China State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong University Xi’an China

In the process of outdoor temperature change, it is beneficial to improve the comfort of thermal users to formulate adjustment and control strategies according to the actual needs of each user. In this paper, different adjustment modes are established according to the thermal comfort of users, and the control strategies of rising and cooling within 0, 30 and 60 minutes are proposed, and the indoor temperature control effect and heating energy consumption of each adjustment mode under different control strategies are analyzed. The results show that: in different modes, when the rise and cooling time increase, compared with the design room temperature, the indoor temperature difference under the control mode is smaller, but the time needed to reach stability is longer. At the same time, the total heat load is unchanged, but the total pump work decreases.

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Research on Bionic Airfoil Design Method Based on Re-Evolution Optimization and Multi Objective Application on Horizontal Axis Wind Turbines

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SSRN 2023年

作者： Wang, Ying Huang, ShengXian Yan, Hua Qiu, HuiHe Shanghai key laboratory of multiphase flow and heat transfer of power engineering School of Energy and Power Engineering University of Shanghai for Science and Technology Shanghai China Department of Mechanical and Aerospace Engineering The Hong Kong University of Science and Technology Clear Water Bay Hong Kong

关键词： Airfoils

Experimental Study on Non-Isothermal Mixing Characteristics of Water in T-Junction

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Experimental Study on Non-Isothermal Mixing Characteristics ...

China Instrument and Control Society (ACCIS), Academic Conference of

作者： Shuhan Liu Wencang Guo Xianliang Lei Zhaojun Yuan Shuqi Meng Desheng Jin State Key Laboratory of Multiphase Flow Engineering Xi'an Jiaotong University Xian China China Nuclear Power Technology Research Institute Co. Ltd. Shen Zhen Guangdong China

ISBN: (数字)9798350350326

ISBN: (纸本)9798350350333

T-junction is an essential component in piping system of various thermal systems. When hot and cold fluid mixing in the T-junction, several compound mechanisms (like turbulent mixing, turbulent penetration, fluid stratification) make the mixing characteristics more complex. To clearly reveal such mixing mechanism with non-isothermal fluids, an experimental study was conducted with Ultrasound Doppler Velocimetry (UDV) and fast-response thermocouples bundle. The results show that the local velocity uncertainty of the UDV is within 10%, the uncertainty of the thermocouple bundle is 0.5°C, and the response time is 66.7 ms. After verification, the mixing characteristics between the main and branch pipe under different momentum ratios and temperature differences were discussed. It is shown that as the momentum ratio decreases, the location of the most intense radial temperature fluctuations and velocity fluctuations shifts towards the lower wall. At the same time, the peak flow rate in the cross-section increases by 35.7% and the main branch fluid mixing is more homogeneous. As the temperature difference increases, the thermal stratification is more pronounced and the velocity fluctuation peak moves towards the upper wall of the pipe.

关键词： Temperature measurement Temperature distribution Fluctuations Fluids Uncertainty Measurement uncertainty Thermocouples Distance measurement Velocity measurement Voltage control

Research on the Performance Enhancement of Accident Tolerant Fuel for Eliminating Core Melting Based on Isaa

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SSRN 2022年

作者： Tang, Shaowei Zhang, Bin Shan, Jianqiang School of Nuclear Science and Technology Xi’an Jiaotong University Shaanxi Xi’an710049 China State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong University Shaanxi Xi’an710049 China

Based on the Integrated Severe Accident Analysis (ISAA) code, this paper studies the influence of thermo-physical properties of Accident Tolerant Fuel (ATF) materials on the plant responses to severe accidents. By selecting ATF with IMDP as the core material and SiC as the cladding material and changing different physical parameters, it is found that fuel density and cladding density have the greatest influence on the fuel temperature rise. In addition, to eliminate core melting, the ATF parameters in ISAA are modified step by step to improve the thermodynamic properties of the fuel, and the core is finally made to reach thermal equilibrium. According to the calculation results, the supporting capacity of the cladding, the supporting capacity of the core supporting plate, and the melting point of the fuel are the main factors limiting the core melting, which can be eliminated by appropriately improving these properties. © 2022, The Authors. All rights reserved.

关键词： Thermodynamic properties

A Gpu-Accelerated Multi-Resolution Lsmps Method for multiphase flows Simulation with Gas-Liquid Phase Transition

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SSRN 2024年

作者： Cao, Sheng Ren, Qianyong Wang, Wenpeng Zhang, Bin Shan, Jianqiang School of Nuclear Science and Technology Xi’an Jiaotong University Shaanxi Xi’an710049 China State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong University Shaanxi Xi’an710049 China

The meshless Lagrangian method (particle method) demonstrates significant advantages in simulating multiphase flows with highly dynamic phase interfaces and has been widely applied in research areas such as ocean engineering, nuclear engineering, and aerospace engineering. The least squares moving particle semi-implicit (LSMPS) method theoretically attains high-order accuracy, significantly enhancing the precision and stability of simulations. However, compared to traditional Eulerian methods, its numerical discretization is more complex and computationally intensive, which limits its applicability in large-scale simulations. To mitigate these challenges, a multi-resolution particle model is implemented to reduce computational costs, and algorithmic improvements and optimizations enable GPU-based parallel processing, significantly boosting computational efficiency. Building on this foundation, a high-precision surface particle detection algorithm and a stable gas-liquid phase transition model are developed. The phase transition model integrates the volume change resulting from phase transition as a source term in the pressure Poisson equation. Benchmark tests of single bubble rising in liquid, Rayleigh-Taylor instability, and two-dimensional horizontal film boiling were conducted to validate the accuracy and efficiency of the GPU- accelerated multi-resolution LSMPS method for simulating multiphase flows, thereby promoting the application of the LSMPS method in both scientific research and practical engineering. © 2024, The Authors. All rights reserved.

关键词： Poisson equation

Effects of Imposing Contact Angle Schemes and Constructing a Special Ghost Fluid Layer on the Heated Substrate in Pseudopotential Lattice Boltzmann Simulation of Sessile Droplet Evaporation

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SSRN 2022年

作者： Wang, Dongmin Cheng, Ping Key Laboratory of Multiphase Flow and Heat Transfer in Shanghai Power Engineering School of Energy and Power Engineering University of Shanghai for Science and Technology Shanghai200093 China School of Mechanical Engineering Shanghai Jiao Tong University Shanghai200240 China Jiangsu Key Laboratory of Micro and Nano Heat Fluid Flow Technology and Energy Application Suzhou University of Science and Technology Suzhou215009 China

The primitive pseudopotential-based scheme (PP scheme), the modified pseudopotential-based scheme (MP scheme) and the improved virtual-density scheme (IVD scheme) are the three most widely used contact angle schemes to simulate wall wetting characteristics in the pseudopotential lattice Boltzmann (LB) model under isothermal conditions. In this paper, these three widely used contact angle schemes are applied to simulate the problem of sessile droplet evaporation on a heated substrate, which is a non-isothermal phase-change process where temperature varies spatially and temporally. It is found that (i) using the PP scheme (primitive pseudopotential-based scheme) and the MP scheme (modified pseudopotential-based scheme) may lead to algorithmic instability problems in certain ranges of contact angles, deformation of droplet interface shape or Marangoni vortices shape, generation of unphysical vortices near the heated substrate, or result in erroneous temperature distributions near droplet triple-phase line. (ii) The IVD scheme (improved virtual-density scheme) has better algorithmic stability than the PP scheme and MP scheme (primitive pseudopotential-based scheme and the modified pseudopotential-based scheme), where the droplet interface shape and Marangoni vortices shape are correct, the unphysical vortices and the erroneous temperature distribution near droplet triple-phase line disappear. (iii) If a special ghost fluid layer (as proposed in this paper) is constructed on the wall when the PP scheme or the MP scheme (primitive pseudopotential-based scheme or the modified pseudopotential-based scheme) is implemented, the instability of the numerical solution is improved, the deformation of droplet interface shape and the Marangoni vortices shape are corrected, and the unphysical vortices near the heated substrate and the erroneous temperature distribution near droplet triple-phase line disappear. The addition of such a special kind of ghost fluid layer at the heated wa

关键词： Vortex flow