The Research On Small Scale Meteorology Model In Imitating Effect Of Urban Landscapeconstruction

With the rapid development of economic and intensifying urbanization, the promptly expansion of city size, population growth, dense buildings, the doubled or redoubled of vehicles and the large quantities of waste gas, waste liquid, tailing and artificial heat release of combustion in urban production and living activities, which making the urban climate changed significantly, the following urban heat island effect become the potential constraints to the further improvement on quality of life and development of the city.In this paper, a detailed description of the complex and diverse urban surface characteristics has been made. A small-scale urban meteorological numerical model has also been established based on the coupling of the energy balance model as well as the dynamic system framework. Through selecting some green space as simulation experiments, a further quantitative analysis demonstrates the considerable influence of the landscape greening construction to the improvement of the quality of thermal environment. This paper is organized as five parts:In partâ… the reserach background and purpose as well meaning has been discussed. A review of the different national and international research approaches has also been made. Partâ…¡is contributed to the construction of the small-scale meteorological numerical model. Using Fortran programming language, this small-scale meteorological numerical model is well suitable to represent the urban energy balance model by coupling the dynamic system framework. The model uses three-dimensional quasi-static equations and k-s turbulence closure scheme, also introduces the effective air volume ratio and form resistance to analyse the influence of urban buildings to the air flow. This model also takes into account the energy balance within the canopy. In partâ…¢, a simulation verification is conducted based on simulating the wind field and thermal field of Temple of Heaven Park. In partâ…£, based on the case study of Temple of Heaven Park, a sensitivity study of discussing the influence of choosing different energy balance parameters in the model to the changes of land surface parameters in the same time period has been analysised. By the trees reflectivity, woodland inverse heat, roughness and length sensitivity tests, an overall result is reached:the different parameters in the surface energy balance equation have different effects on the land surface temperature. In part V:The effects of different scales of green land on the temperature has been discussed. Using the same model the wind field and thermal field of Nanhu Park are also been simulated, prove that different scales of green land do contribute differently to the mitigation of urban heat island phenomenon, basically a larger scale green land has a much more apparent cooling effect.This paper laid the foundation to an accurate and objective forecast and review of the wind thermal environment of green land. Provide a comprehensive solution to the parameters processing, meteorological data acquisition as well as grid processing so make it feasible to understand the characteristics of wind-thermal environment of green space within the urban canopy, also provide a practical way to improve the wind thermal environment by simulation guide and optimized green land design.