On July 14, the 2008 Summer Olympic Venue Design Competition concluded with a U.S.-China joint venture scooping the first prize. The event was held for the conceptual designs of two major venues for the Games ?the Oly...On July 14, the 2008 Summer Olympic Venue Design Competition concluded with a U.S.-China joint venture scooping the first prize. The event was held for the conceptual designs of two major venues for the Games ?the Olympic Green and the Wukesong Culture and Sports Center. A total of 87 plans were submitted since the contest was opened in April, 54 for the Olympic Green and 33 for the Wukesong Center.San Francisco-based Sasaki Associates won the top prize for the Olympic Green which was designed in partnership with Tianjin展开更多
Small propeller-type wind turbines have a low Reynolds number,limiting the number of usable airfoil materials.Thus,their design method is not sufBciently established,and their performance is often low.The ultimate goa...Small propeller-type wind turbines have a low Reynolds number,limiting the number of usable airfoil materials.Thus,their design method is not sufBciently established,and their performance is often low.The ultimate goal of this research is to establish high-performance design guidelines and design methods for small propeller-type wind turbines.To that end,we designed two rotors:Rotor A,based on the rotor optimum design method from the blade element momentum theory,and Rotor B,in which the chord length of the tip is extended and the chord length distribution is linearized.We examined performance characteristics and flow fields of the two rotors through wind tunnel experiments and numerical analysis.Our results revealed that the maximum output tip speed ratio of Rotor B shifted lower than that of Rotor A,but the maximum output coefficient increased by approximately 38.7%.Rotors A and B experienced a large-scale separation on the hub side,which extended to the mean in Rotor A.This difference in separation had an impact on the significant decrease in Rotor A's output compared to the design value and the increase in Rotor B's output compared to Rotor A.展开更多
文摘On July 14, the 2008 Summer Olympic Venue Design Competition concluded with a U.S.-China joint venture scooping the first prize. The event was held for the conceptual designs of two major venues for the Games ?the Olympic Green and the Wukesong Culture and Sports Center. A total of 87 plans were submitted since the contest was opened in April, 54 for the Olympic Green and 33 for the Wukesong Center.San Francisco-based Sasaki Associates won the top prize for the Olympic Green which was designed in partnership with Tianjin
文摘Small propeller-type wind turbines have a low Reynolds number,limiting the number of usable airfoil materials.Thus,their design method is not sufBciently established,and their performance is often low.The ultimate goal of this research is to establish high-performance design guidelines and design methods for small propeller-type wind turbines.To that end,we designed two rotors:Rotor A,based on the rotor optimum design method from the blade element momentum theory,and Rotor B,in which the chord length of the tip is extended and the chord length distribution is linearized.We examined performance characteristics and flow fields of the two rotors through wind tunnel experiments and numerical analysis.Our results revealed that the maximum output tip speed ratio of Rotor B shifted lower than that of Rotor A,but the maximum output coefficient increased by approximately 38.7%.Rotors A and B experienced a large-scale separation on the hub side,which extended to the mean in Rotor A.This difference in separation had an impact on the significant decrease in Rotor A's output compared to the design value and the increase in Rotor B's output compared to Rotor A.
