It is highly important in Japan to choose a good site for wind turbines, because the spatial distribution of wind speed is quite complicated over steep complex terrain. We have been developing the unsteady numerical m...It is highly important in Japan to choose a good site for wind turbines, because the spatial distribution of wind speed is quite complicated over steep complex terrain. We have been developing the unsteady numerical model called the RIAM-COMPACT (Research Institute for Applied Mechanics, Kyushu University, Computational Prediction of Airflow over Complex Terrain). The RIAM-COMPACT is based on the LES (Large-Eddy Simulation). The object domain of the RIAM-COMPACT is from several m to several km, and can predict the airflow and gas diffusion over complex terrain with high precision. In the present paper, the design wind speed evaluation technique in wind turbine installation point by using the mesoscale meteorological model and RIAM-COMPACT CFD model was proposed. The design wind speed to be used for designing WTGs can be calculated by multiplying the ratio of the mean wind speed at the hub-height to the mean upper-air wind speed at the inflow boundary, i.e., the fractional increase of the mean hub-height wind speed, by the reduction ratio, R. The fractional increase of the mean hub-height wind speed was evaluated using the CFD simulation results. This method was proposed as Approach 1 in the present paper. A value of 61.9 m/s was obtained for the final design wind speed, Uh, in Approach 1. In the evaluation procedure of the design wind speed in Approach 2, neither the above-mentioned reduction rate, R, nor an upper-air wind speed of 1.7 Vo, where Vo is the reference wind speed, was used. Instead, the value of the maximum wind speed which was obtained from the typhoon simulation for each of the investigated wind directions was adopted. When the design wind speed was evaluated using the 50-year recurrence value, the design wind speed was 48.3 m/s. When a somewhat conservative safety factor was applied, that is, when the 100 year recurrence value was used instead, the design wind speed was 52.9 m/s.展开更多
目前设计领域都在向着数字化迈进,其中在建筑与城市规划领域以BIM(Building Information Modeling)和CIM(City Information Modeling)的研究最为成熟,但在小区域精准落地的风景园林设计中,数字化的应用仍处于起步阶段,尤其在场地规模较...目前设计领域都在向着数字化迈进,其中在建筑与城市规划领域以BIM(Building Information Modeling)和CIM(City Information Modeling)的研究最为成熟,但在小区域精准落地的风景园林设计中,数字化的应用仍处于起步阶段,尤其在场地规模较小且原始地形可塑潜质较差的沟道地形的辅助设计中,数字化研究和应用仍处于空白。以可塑性较差的西宁市某沟道公园的原始地形为对象,利用Rhino+Grasshopper编程插件分析地形,通过开源端口Python代码与遗传算法辅助地形低影响优化设计,实现土方量最小,为不同设计方案经济比选提供支撑。最终完成场地地形模型的构建,并具备低影响开发必要条件,且设计与施工之间拟合度较高,从而确保了设计开发工作的可行性。展开更多
文摘It is highly important in Japan to choose a good site for wind turbines, because the spatial distribution of wind speed is quite complicated over steep complex terrain. We have been developing the unsteady numerical model called the RIAM-COMPACT (Research Institute for Applied Mechanics, Kyushu University, Computational Prediction of Airflow over Complex Terrain). The RIAM-COMPACT is based on the LES (Large-Eddy Simulation). The object domain of the RIAM-COMPACT is from several m to several km, and can predict the airflow and gas diffusion over complex terrain with high precision. In the present paper, the design wind speed evaluation technique in wind turbine installation point by using the mesoscale meteorological model and RIAM-COMPACT CFD model was proposed. The design wind speed to be used for designing WTGs can be calculated by multiplying the ratio of the mean wind speed at the hub-height to the mean upper-air wind speed at the inflow boundary, i.e., the fractional increase of the mean hub-height wind speed, by the reduction ratio, R. The fractional increase of the mean hub-height wind speed was evaluated using the CFD simulation results. This method was proposed as Approach 1 in the present paper. A value of 61.9 m/s was obtained for the final design wind speed, Uh, in Approach 1. In the evaluation procedure of the design wind speed in Approach 2, neither the above-mentioned reduction rate, R, nor an upper-air wind speed of 1.7 Vo, where Vo is the reference wind speed, was used. Instead, the value of the maximum wind speed which was obtained from the typhoon simulation for each of the investigated wind directions was adopted. When the design wind speed was evaluated using the 50-year recurrence value, the design wind speed was 48.3 m/s. When a somewhat conservative safety factor was applied, that is, when the 100 year recurrence value was used instead, the design wind speed was 52.9 m/s.
文摘目前设计领域都在向着数字化迈进,其中在建筑与城市规划领域以BIM(Building Information Modeling)和CIM(City Information Modeling)的研究最为成熟,但在小区域精准落地的风景园林设计中,数字化的应用仍处于起步阶段,尤其在场地规模较小且原始地形可塑潜质较差的沟道地形的辅助设计中,数字化研究和应用仍处于空白。以可塑性较差的西宁市某沟道公园的原始地形为对象,利用Rhino+Grasshopper编程插件分析地形,通过开源端口Python代码与遗传算法辅助地形低影响优化设计,实现土方量最小,为不同设计方案经济比选提供支撑。最终完成场地地形模型的构建,并具备低影响开发必要条件,且设计与施工之间拟合度较高,从而确保了设计开发工作的可行性。
