管道中的

The front panel of the baseboard channel is removable, and outlets may be placed at any point along the channel.

踢脚板管道的前面板可以移动，而电源插座可以安放在管道中的任意位置。

The Geothermal heating radiator is to replace the method has many advantages, but the iron in the boiler and piping rust, groundwater, water scale, timing and other high-temperature heating conditions for the one-time approach which it can not replace the pipeline pipe and can not guarantee that from the use of requirements and life.

地热取代散热器的取暖方法优点很多，但铁锅炉及管道中的铁锈、地下水，自来水的水垢、定时高温供热等这些条件，使一次性埋管做法无法更换管道，从根本无法保证使用要求及使用寿命，后患无穷，这也是业内人士共同担忧的问题，改变方法势在必行。

At the same time, combining with the actual condition of delivery pipeline of our country and some prevalent leak detection and location methods, this paper raised a method, which is based on wavelet analysis and negative- pressure-wave to detect and locate the leakage. Jobs in the paper are as follows:As affected by gas density, pressure, specific heat and pipe material, the velocity of negative-pressure-wave improved depending on the energy conservation. At one time, taking the affection of velocity of gas flow, the location formula was modified in some degree.When locating the leaks with location formula, the iterative approach algorithm was adopted as a new method to increase the location accuracy level of system.Multi-scale decomposition and reconstruction of wavelet transform is utilized to filter the noise of negative-pressure-wave, which was brought by leakage. With the capacity to detect the signal singularity fast and accurately, wavelet transform was used to catch the break point of pressure signal. The work improved the accuracy of At in location formula, accordingly improved the location accuracy.Wavelet is a suitable tool for signal analysis. The distinct character is that the mother-wavelet is of optional. That means choosing different mother-wavelet will get different analysis result. So we studied how to choose mother-wavelet and its scale for signal singularity detection. The method is to choose a wavelet by regularities of the wavelet and the signal.Finally, a plan, which bases on SCADA system for inspection and detection of natural gas leakage, is proposed in the article.

其中，主要进行了以下几方面的工作：针对泄漏产生的负压波在管道中的传播速度受媒介的密度、压力、比热及材质等因素的影响，而非声波在空气中传播的速度，本文利用能量守恒原理，对其进行了修正；考虑到管内气体流速对压力波速的影响，对原始的负压波定位公式进行了一定程度的改进，并在利用定位公式进行泄漏点定位时采用逐步迭代逼近算法，提高了系统的定位精度；利用小波变换的多分辨率分解和重构技术，对采集到的管道发生泄漏时产生的负压波信号进行了降噪处理；并利用小波变换技术对信号奇异点的快速、准确的识别能力，对经上述消噪后的负压波信号进行了奇异点捕捉，精确捕捉的结果提高了定位公式中上下游站点采集到的负压波奇异点的时间差△t的精度，从而进一步提高了定位的精度；考虑到小波变换是一种基波可变的信号分析工具，也就是说，不同的小波基波对信号分析的结果将有很大差别，这势必影响最终的处理结果，因此，我们又对比分析了本课题中小波基及尺度的选择问题，依据规则性系数相似性原理对母小波的选择进行了探索性研究；最后，还提出了基于SCADA的泄漏检测与定位系统的软件开发构想及系统的嵌入方案。

The flow field of the PCCP pipeline is simulated, so the head loss and resistance coefficient are calculated which are consistent with the test data. Additionally, other pipelines of different diameter are also simulated, and the resistance coefficient's law along with the diameter is carried out.

对PCCP管道中的水流流场进行数值模拟，计算并求解出管道的水头损失和阻力系数，与模型试验取得了较为一致的结果；另外，还对不同管径的管道进行了模拟，得到了阻力系数随管径的变化规律。

According to the existing toilet bowl pipeline shape produced by some enterprises,the effect on the pipeline siphonage which is caused by the alterations of hydraulic packing control point was investigated with the hydrodynamics calculation in this paper.

该文从企业现有的坐便器管道形状入手，首先应用水动力学知识计算水封控制点位置的变化对管道虹吸性能的影响，然后基于计算结果提出更优位置的假设，并依据试验确定其合理的变化范围，最后通过CFD方法模拟改进前后管道中的虹吸速度和虹吸压力，结果表明管道虹吸性能得到了优化。

The transducer, which is coaxially connected with the transport pipeline, does not disturb the flow state and has the features of ruggedness and durability, it is especially suitable for industry process control.

基于极化电荷的流量传感器不仅结构简单、寿命长，而且与气输管道同轴密封连接，不影响粉粒体在管道中的流动状态，因此特别适合于工业过程控制。

Before installing the trap must use pressurized steam blowing pipe, clear pipe of debris.

在安装疏水阀之前一定要用带压蒸汽吹扫管道，清除管道中的杂物。

It is determined as a result of heating facilities, regular and high-temperature heating. It operated hot water pipes so that in the 15 ℃---- 90 ℃ from time to time between the operation, resulting in accelerated aging boiler and pipe rust and scale in the United States on heating and heating from time to time out after a period of time. The purpose is to accelerate the pipeline of the scale and rust solid precipitation knot a few years later so easy to plug.

由于供热设施所决定，定时和高温供热，使热水管在15℃----90℃之间不定时运行，产生热胀冷缩加速老化，锅炉和管道中的铁锈和水垢在美日定时供热和取暖期过后停用时间，加速管道的水垢与铁锈的沉淀结固，几年后，使管理易产生堵塞。

The three-dimensional finite element model of guided wave in the pipe was built by the finite element method.

利用有限元方法建立管道导波3-D模型，通过在管道中激励纵向超声波，模拟导波在管道中的传播形态。

The mode simulated the propagation of guided wave in a pipe by applying the longitudinal ultrasonic to the pipe end.

利用有限元方法建立管道导波3-D模型，通过在管道中激励纵向超声波，模拟导波在管道中的传播形态。

Plunder melds and run with this jewel!

掠夺melds和运行与此宝石！

My dream is to be a crazy growing tree and extend at the edge between the city and the forest.

此刻，也许正是在通往天国的路上，我体验着这白色的晕旋。