The wind engineering research group of Chongqing University (CQU) led by Prof. Qingshan Yang and Prof. Yukio Tamura was invited to visit Japan for academic exchange and cooperation by Kyushu University and Tokyo Polytechnic University (TPU) from March 7 to March 15, 2019. , Prof. Hui Yi, Associate Professor Bowen Yan and Dr. Li Ke also took part in the visit.

On March 8, 2019, Prof. Qingshan Yang and Prof. Yukio Tamura were invited by Prof. Yuji Ohya to visit Kyushu University for academic coordination and communication. Associate Prof. Koichi Watanabe and Associate Prof. Takanori Uchida from Institute of Applied Mechanics of Kyushu University also attended the meeting. First of all, Prof. Ohya reviewed the history and development in the field of wind power at Kyushu University and then introduced the recent progress in diffusion-enhanced wind turbines (Windlens turbine), multi-rotor systems (MRS), and floating wind power generation systems. Associate Professor Uchida gave a brief introduction on his RIAM-COMPACT numerical simulation platform and the application in urban wind environment, mountainous wind field and wind turbine wake model. And Associate Professor Watanabe presented the wind-solar-chimney which is co-developed with Prof. Ohya. They brought forward for the recent developments and application prospects in distributed wind energy and urban pollutant dispersion. Dean Prof. Qingshan Yang introduced the general situation of civil engineering disciplines in Chongqing University and Chongqing City, and presented the recent progress achieved by the wind engineering center of Chongqing University in the past two years. In addition, Prof. Yang suggested to continue enhancing cooperation and academic exchange with Institute of Wind Power of Kyushu University as well as carrying out joint postgraduate program. Then, Prof. Qingshan Yang presented the wind-resistant design of large-scale roof structures. Moreover, Dr. Bowen Yan gave a lecture pertinent to wind effects on super-tall buildings and wind energy assessment of complex terrain. Dr. Li Ke presented the wind-induced vibration control of long-span bridges. After the seminar, Prof. Ohya said that CQU and Kyushu University have established a close relationship and have the common research foundation and interests. He called on both sides to continue promoting cooperation and enhancing communication. In the end, he also mentioned about the delegation of Kyushu University will visit our university to carry out academic exchanges and cooperative research.

Fig.1 Prof. Qingshan Yang and Prof. Yukio Tamura visited the laboratory of Kyushu University accompanied by Prof. Ohya

Fig.2 Prof. Qingshan Yang gave the lecture at Kyushu University

Fig. 3 Associate Professor Yan Bowen addressed the lecture at Kyushu University

Fig. 4 Dr. Li Ke gave his presentation at Kyushu University

Prof. Qingshan Yang together with Associate Prof. Bowen Yan and Dr. Li Ke visited the TPU Wind Tunnel Laboratory on March 10, 2019. During the visit, they had communicated with Prof. Yong Chul Kim, the director of the Wind Tunnel Laboratory, regarding the operation and maintenance of the wind tunnel laboratory. Prof. Kim pointed out that it is necessary to consider the blocking effects of traverse system on the flow quality in the wind tunnel. He also suggested that the noise reduction measures, sound insulation, regular maintenance and standardized management of equipment.

Fig.5 Attend International Workshop in Tokyo Polytechnic University

Prof. Qingshan Yang and Prof. Yukio Tamura attended the opening ceremony of International Workshop on Wind Effects on Buildings and Urban Environment on March 11, 2019. Prof. Yukio Tamura made an important speech at the opening ceremony and gave the report entitled "Pedestrian-level wind speed around isolated square type buildings: Effect of height, width, aspect ratio".

Associate Professor Bowen Yan made a report entitled "Wind tunnel experiments and Numerical simulations of pedestrian-level wind environment around groups of tall buildings: effects of building shape, layout and local wind climate". In addition, Professor Hui Yi gave a report entitled "Effects of surface roughness on the local pressure of high-rise building" .

Fig. 6 Prof. Yukio Tamura gave an opening speech at TPU International Workshop

Fig. 7 Associate Professor Bowen Yan gave a report at the TPU International Workshop

Fig. 8 Prof. Yi Hui gave a report at the TPU International Workshop

Prof. Qingshan Yang and Prof. Yukio Tamura met with Mr. Atsushi Yamada, the director of Mitsubishi Heavy Industries Machinery Co., Ltd. on the morning of March 12, 2019 while attending International Workshop on Wind Effects on Buildings and Urban Environment in TPU. Mr. Yamada introduced key projects of Mitsubishi Heavy Industries in heavy machinery, high-precision instruments and large-scale infrastructure, including Toyota Wind Tunnel and Japan E-defense full-scale shaking table. Prof. Qingshan Yang briefed Mitsubishi Heavy Industries on the general situation of major civil engineering disciplines in Chongqing University and Chongqing City. Prof. Yang then introduced the construction plan for the large-scale recirculation wind tunnel of Chongqing University to Mitsubishi Heavy Industries. Both sides had a further communication and exchange on the feasibility, technical parameters, critical design and manufacture issues of the wind tunnel construction plan of Chongqing University. In the afternoon, CQU research group together with Prof. Kawai and Prof. Shuyang Cao from Tongji University have met with a group of delegates from Kawasaki Heavy Industries Machinery Co., Ltd.  Both sides have exchanged the thoughts on the expected completion time of the wind tunnel construction plan of Chongqing University, the joint construction of civil and wind tunnels, the project bidding method, the feasibility analysis of the wind tunnel and the comparison and selection methods. 

Fig.9 Prof. Qingshan Yang discussed the construction plan of major wind tunnels with representatives of Mitsubishi Heavy Industries.

Fig. 10 Visit the RTRI Large Scale Low Noise Wind Tunnel Laboratory

Prof. Qingshan Yang and Prof. Yukio Tamura visited the Large Scale Low Noise Wind Tunnel Laboratory of the Railway Technical Research Institute (RTRI) at Maibara, Japan on March 13, 2019. First of all, the director of RTRI Wind Tunnel Institute briefly introduced the history and development of RTRI Wind Tunnel Laboratory. Later, Prof. Qingshan Yang and Prof. Yukio Tamura visited the wind tunnel laboratory and learned about the specific construction process and operation of the heat exchange section, the contraction section, the power section, the test section and the model preparation room of the wind tunnel laboratory. After that, Prof. Qingshan Yang together with other CQU delegates and Prof. Shuyang Cao had a technical meeting with the researchers from RTRI Wind Tunnel Laboratory and both sides came to an agreement on future joint experiments in the Maibara Wind Tunnel Laboratory which enabled the further cooperation, and exchanged the opinions about the investment and construction process, staff operation, management and maintenance etc.

Fig.11 Visit RTRI Research Center Headquarters

Prof. Qingshan Yang visited headquarters of Tokyo Railway Technology Research Institute (RTRI) on March 14, 2019. Dr. Toru Miyauchi and Ms. Eriko Kimoto, directors of International Business Department in RTRI showed their warm welcome to CQU. Ms. Miyauchi briefly introduced the history and development and current situation of RTRI, which is a Japanese research institute specialized in in railway technology research. Founded in 1986 by Japan National Railways, it officially operated and inherited the technical development departments of the former Japan National Railways, the Railway Technology Research Institute and the Railway Labor Science Research Institute after the privatization of the National Railways in 1987. The research facilities mainly include the Wind Tunnel laboratory and Yanzawa Snow Damage Prevention Laboratory, and Hino Civil Engineering Laboratory et al. Later, Prof. Qingshan Yang visited the advanced experimental research equipment such as the maglev train test site, the train brake test lab, the large-scale shaking table and the large-scale full-scale rainstorm test lab. After the visit, Prof. Qingshan Yang had technical exchanges with Dr. Yutaka Sakuma, bchief researcher of vehicle aerodynamic characteristics of RTRI Environmental Engineering Research Department, discussing key technical problems such as aerodynamic performance optimization, aerodynamic noise reduction measures and sonic booms for Shinkansen trains. Dr. Suzuki, Prof. Shuyang Cao, Associate Prof. Bowen Yan and Dr. Li Ke also accompanied the visit to Tokyo Railway Technology Research Institute.