论文部分内容阅读
暖通空调工程中的风道,通常采用圆形或矩形风道,它的沿程摩擦阻力,习惯上用“当量直径法”,但在特殊场合,有利用建筑空间不另设风道,也有结合建筑空间设置非标准断面的风道,如地下隧道的上、下部为弓形、拱形的通道;水电站溢流厂房的三角廊道等。其形状是多样的:有弓形、梯形、三角形马蹄形等,如图1所示。这类风道的沿程摩擦阻力的计算,利用现有书刊中的公式,图表均不能解决。随着近期地下工程的日益增多,各种不同断面风道使用得更为广泛,广大设计者迫切希望能研究出一种适用于任意断面风道的沿程摩擦阻力计算法。作者根据多年的工程实践,探讨了这一计算
The ducts in HVAC projects usually use round or rectangular air ducts. The friction resistance along the way is customarily used in the “equivalent diameter method”. However, in special occasions, there is no separate air duct for the use of building space. In combination with the building space, wind tunnels with non-standard sections are to be provided, such as arched and arched tunnels at the upper and lower parts of underground tunnels, and triangle corridors of overflow plants at hydropower stations. Its shape is varied: there are arches, trapezoids, triangular horseshoes, etc., as shown in Figure 1. The calculation of the frictional resistance along this type of air duct can not be solved by using the formulas in the existing books and magazines. With the increasing number of underground projects recently, various sections of wind tunnels are used more widely. Designers are eager to develop a friction resistance calculation method that can be applied to arbitrary sections of wind tunnels. The author explores this calculation based on years of engineering practice.