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The cross-runway is still a new runway configuration in my country,and its operation safety and efficiency need to establish relevant standards and evaluation methods,and establish a safe separation for the possible track crossing of the approaching aircraft and the departing aircraft.Firstly,the distance from the approaching aircraft to the end of the runway is calculated by establishing a collision risk model;then a wake separation model between the approaching and departing aircraft across the runway is established,and whether the wake generated by the departing aircraft will affect the approaching go-around aircraft is obtained.So as to determine the wake safety separation;finally,compare the safety separation calculated by the collision risk model with the safety separation calculated by the wake model,and take the largest one as the final safety separation;taking the takeoff aircraft B747 and approach aircraft B737 as examples.When considering the wake factor,the calculated minimum safe separation value of 6 km is less than the current operating separation standard of Daxing Airport,which is 12 km,which further optimizes the operating separation standard of Daxing Airport′s cross-runway.

[Introduction] The paper aims to obtain the optimal layout of offshore wind farm and gain the maximum profit in the project life-cycle, it is high necessary to analyze its impact factors. [Method] The own developed application was used to compare the wake models between Jensen and Larsen, different superposition algorithm among wind turbines and the interannual variability of wind direction, this disquisition had combined the practical offshore wind farm case to analyse and provide the optimal layout. [Result] The results we obtained demonstrate that the interannual variability of wind direction is the most key factor to layout, followed by the different wake model, with superposition algorithm least. [Conclusion] This work provides some guidance for further project on choosing the optimal layout, thus the billions of dollars in losses caused by interannual variability of wind direction can be avoided in life-cycle of 25 years.

This paper studied its application of WindPRO software in practice teaching in colleges and universities. Considering either no wake model or N.O. Jensen wake model, the simulation of power generation of wind farm were carried out. When the N.O. Jensen wake model was considered, the simulation of optimizing the ordinary arrangement of wind turbine was carried out. The results of experiment were compared and analyzed, which helped students of colleges and universities to understand and master the professional knowledge of wind resources, wake effect and site arrangement of wind turbine or other wind power knowledge; promote students to translate the textbook knowledge into practical ability, and verify and expand theoretical teaching The teaching achieves the purpose of practical teaching reform in Colleges and Universities. [ABSTRACT FROM AUTHOR]

A design and analysis procedure for rotor blades is developed based on vortex theory. Based on free wake model, the aerodynamic performances of horizontal axis wind turbine rotor by adding spiroid O winglets and L winglet at the tip of the blade are studied numerically, the vortex location and induced velocity distribution in different conditions are investigated. The results show that the presence of winglet at the tip of the wind turbine blade improves the power coefficient at the design wind speeds, and downwind winglets are superior to upwind ones with respect to optimization of power. [ABSTRACT FROM AUTHOR]

The earthquake input directions affect seismic response of free spanning submarine pipeline. A hydrodynamic force model improved from Wake model considering three dimensional excitation inputs is presented. Equations of motion are derived from the improved Wake model on the basis of finite element method. Finite element model is established to simulate the experimental conditions. The numerical results subjected to sine wave input and simulated El Centro earthquake input are obtained. The comparison of numerical and experimental results shows that the Wake model considering excitation directions could satisfactorily predict dynamic response of free spanning submarine pipelines under earthquake, and the numerical results are in agreement with the experimental ones. [ABSTRACT FROM AUTHOR]