The fluid dynamic behavior of feeding gas (TiCI4) in an annular channel affects the combination of 02 and TiCI4 in an oxidation reactor, a key piece of equipment in titanium pigment production. The numerical procedu...The fluid dynamic behavior of feeding gas (TiCI4) in an annular channel affects the combination of 02 and TiCI4 in an oxidation reactor, a key piece of equipment in titanium pigment production. The numerical procedure was validated by a 3-dimensional gas flow in the annular channel. Applying the validated model, the flow character- istics of TiCl4 in the oxidation reactor with a tangential inlet were simulated and characterized. The flow distribu- tion with five rectifying rings of different structure was simulated and analyzed. The results showed that the rectifying ring improved the distribution uniformity of the pressure and outlet velocity. Compared to the original case without a rectifying ring, the non-uniformity of the pressure and outlet velocity could be reduced by up to 91% and 69% respectively. The rectifying ring #5, which can be installed and adjusted easily, is more effective in realizing even distribution. In addition, installation of the rectifying ring effectively reduced the circulating flow in an annular channel as well as the total energy loss.展开更多
The aim of this paper is to illustrate the benefits,and challenges towards providing multifunctional urban green spaces.The results are based on critical analysis of study findings from different cities in Europe,Amer...The aim of this paper is to illustrate the benefits,and challenges towards providing multifunctional urban green spaces.The results are based on critical analysis of study findings from different cities in Europe,America and to a lesser extent in Asia.Inner-city green spaces are especially important for improving air quality through uptake of pollutant gases and particulates which are responsible for respiratory infections.Due to their amenity and aesthetics,green spaces increase property value.To ensure multifunctional role of urban a green space is achieved,in particular the social and psychological role,certain standards of quantity,quality and distribution within the urban area should be adequately established.Green spaces need to be uniformly distributed throughout the city area,although each does not need to be extremely large but should be large enough to accommodate the city population.展开更多
基金Supported by the National Natural Science Foundation of China(21566015,51404123)the Applied Basic Research Projects of Yunnan(2013FC002,2013FC003,2015FB126)the Provincial Personnel Training Funds of Yunnan Province of China(KKSY201352109,KKPT201563013)
文摘The fluid dynamic behavior of feeding gas (TiCI4) in an annular channel affects the combination of 02 and TiCI4 in an oxidation reactor, a key piece of equipment in titanium pigment production. The numerical procedure was validated by a 3-dimensional gas flow in the annular channel. Applying the validated model, the flow character- istics of TiCl4 in the oxidation reactor with a tangential inlet were simulated and characterized. The flow distribu- tion with five rectifying rings of different structure was simulated and analyzed. The results showed that the rectifying ring improved the distribution uniformity of the pressure and outlet velocity. Compared to the original case without a rectifying ring, the non-uniformity of the pressure and outlet velocity could be reduced by up to 91% and 69% respectively. The rectifying ring #5, which can be installed and adjusted easily, is more effective in realizing even distribution. In addition, installation of the rectifying ring effectively reduced the circulating flow in an annular channel as well as the total energy loss.
文摘The aim of this paper is to illustrate the benefits,and challenges towards providing multifunctional urban green spaces.The results are based on critical analysis of study findings from different cities in Europe,America and to a lesser extent in Asia.Inner-city green spaces are especially important for improving air quality through uptake of pollutant gases and particulates which are responsible for respiratory infections.Due to their amenity and aesthetics,green spaces increase property value.To ensure multifunctional role of urban a green space is achieved,in particular the social and psychological role,certain standards of quantity,quality and distribution within the urban area should be adequately established.Green spaces need to be uniformly distributed throughout the city area,although each does not need to be extremely large but should be large enough to accommodate the city population.