Many recent studies have confirmed the existence of liquid slip over particular types of solid surfaces, and these so-called super-hydrophobic surfaces have been shown to generate effective liquid slip because of the ...Many recent studies have confirmed the existence of liquid slip over particular types of solid surfaces, and these so-called super-hydrophobic surfaces have been shown to generate effective liquid slip because of the air trapped between the surface structures. In this paper, based on boundary layer theory, the microscopic structure of the super-hydrophobic surface is analyzed. The liquid slip effect on friction-reduction over super-hydrophobic surfaces under various flow conditions is investigated by experiments with a flume and water tunnel. The experimental results show that the greatest amount of drag-reduction that can be achieved is 8.76% at a low Re.展开更多
With the rapid development of construction engineering and municipal engineering in recent years, water supply and drainage technology has gradually matured. Building water supply and drainage design contains the desi...With the rapid development of construction engineering and municipal engineering in recent years, water supply and drainage technology has gradually matured. Building water supply and drainage design contains the design of rainwater drainage, sewage drainage design, water supply design and fire water supply design. At present, the research on the life cycle assessment of urban drainage system is mainly focused on the sewage treatment plant, therefore in this paper we introduce the theoretical basis of life cycle assessment. In the era of information network, building information model(BIM) technology is widely applied to the design of building water supply and drainage, which and effectively improves the design effi ciency, and makes up for the traditional water supply and drainage design of a lot of problems. In this paper, we analyze the development trend of water supply and drainage engineering based on life cycle assessment and building information model.展开更多
文摘Many recent studies have confirmed the existence of liquid slip over particular types of solid surfaces, and these so-called super-hydrophobic surfaces have been shown to generate effective liquid slip because of the air trapped between the surface structures. In this paper, based on boundary layer theory, the microscopic structure of the super-hydrophobic surface is analyzed. The liquid slip effect on friction-reduction over super-hydrophobic surfaces under various flow conditions is investigated by experiments with a flume and water tunnel. The experimental results show that the greatest amount of drag-reduction that can be achieved is 8.76% at a low Re.
文摘With the rapid development of construction engineering and municipal engineering in recent years, water supply and drainage technology has gradually matured. Building water supply and drainage design contains the design of rainwater drainage, sewage drainage design, water supply design and fire water supply design. At present, the research on the life cycle assessment of urban drainage system is mainly focused on the sewage treatment plant, therefore in this paper we introduce the theoretical basis of life cycle assessment. In the era of information network, building information model(BIM) technology is widely applied to the design of building water supply and drainage, which and effectively improves the design effi ciency, and makes up for the traditional water supply and drainage design of a lot of problems. In this paper, we analyze the development trend of water supply and drainage engineering based on life cycle assessment and building information model.