通风管道设计阻力平衡需要怎么处理？

发布人：http://www.sftfgd.com   发布时间：2018-06-21 11:58:14

一、在通风系统中的通风管道是相互连接的一个整体，必然得遵循各支路阻力平衡规律，当风管系统的结构 形式、管道尺寸一经确定，在一定的风机作用下，各段的风量是按阻力平衡规律自动分配的。在设计计算时未经阻力平衡计算，会导致系统实 际风量分配与设计不符。当然我们也可以通过调节风阀来分配风量，但这样一来就又使非较不利环路的风压多余。所以在设计计算时考虑各环 路的阻力平衡具有现实意义。

First, the ventilation pipe in the ventilation system is a whole which is connected to each other. It must follow the law of resistance balance of each branch. When the structure form and pipe size of the wind pipe system are determined, under the action of a certain fan, the air volume of each section is automatically divided according to the law of resistance balance. In the design calculation, the calculation of the actual air volume does not match the design without the calculation of the resistance balance. Of course, we can adjust the air volume by adjusting the air valve, but this will make the wind pressure of the non most unfavorable loop redundant. Therefore, it is of practical significance to consider the resistance balance of each loop when designing and calculating.

然而，不少设计人员在进行风道水力计算及阻力平衡过程中仅仅凭经验估算或查图手算，这样费时费力还达不到理想效果。笔者所设计的计算 软件以excel为工作平台，用vba语言为开发工具，从而确保了程序的执行效率。

However, many designers only use experience estimation or map hand calculation in the process of wind tunnel hydraulic calculation and resistance balance, so that time consuming and hard work can not reach the ideal effect. The computing software designed by the author takes excel as the working platform and VBA language as the development tool, so as to ensure the efficiency of the program execution.

二、阻力自动平衡计算的基本步骤

Two, the basic steps of the automatic balance calculation of resistance

风道系统阻力平衡自动计算的执行过程基本延用常规设计的计算步骤，主要如下：

The implementation of automatic calculation of resistance balance in duct system basically extends the conventional design calculation steps, mainly as follows:

①将各节点间的逻辑关系、管段的相关参数依次输入并保存，然后根据技术要求初步选定各管段的假定风速;

First, input the logical relationship between the nodes and the relevant parameters of the pipe in sequence, and then according to the technical requirements, the assumed wind speed of each section is preliminarily selected.

②根据假定风速自动计算管段当量水力直径及阻力损失;

2. According to the assumed wind speed, the equivalent hydraulic diameter and resistance loss of the pipe section are automatically calculated.

③用节点逆寻法自动查找系统各环路的路径及阻力损失，并确定系统较不利环路;

(3) find the path and resistance loss of each loop automatically by node inverse search method, and determine the most unfavorable loop of the system.

④对非不利环路进行自动阻力平衡。

(4) the automatic resistance balance is carried out on the non unfavorable loop.

⑤对计算结果进行校核。

Check the results of the calculation.

以上过程中只有工作量不大①、⑤需人工干预，而其他步骤全部由计算机自动完成。从而不但确保其计算速度及准确性，而且还可根据需要进 行适当的手工调整。

In the above process, there is only a small amount of work and manual intervention. All other steps are automatically completed by the computer. It not only ensures the speed and accuracy of calculation, but also adjusts manually according to needs.