1) water circulation coefficient
水循环系数
2) recirculation factor
循环系数
1.
The effect of recirculation factor on the main parameters of non steady controlled recirculation system;
循环系数对非稳态可控循环通风系统主要参数的影响
3) circulating water system
循环水系统
1.
Discussion about the relationship between corrosion and total iron in circulating water systems;
循环水系统腐蚀与总铁关系探讨
2.
On-line chemical cleaning of circulating water system;
循环水系统在线化学清洗的现场实施
3.
Unshut - down chemical cleaning of mazut catalysis circulating water system;
重油催化循环水系统的不停车化学清洗
4) water circulation system
循环水系统
1.
Through the investigation and analysis on the corrosion situation of 5 ℃ water circulation system in the production of PVC by calcium carbide method,reasons for the corrosion failure were discussed as well as the influencing factors,and the corresponding protection methods were proposed.
通过对PVC生产过程中5℃循环水系统腐蚀状况的调查分析,探讨了其腐蚀失效原因及影响因素,提出了相应的防护措施。
2.
The stabilizing agent of water quality especially for the corrosion and incrustation is developed out through test for the water circulation system of blast furnace body.
针对高炉炉体循环水系统的腐蚀与结垢倾向,通过实验找出了水质稳定药剂,实际生产运行结果表明循环水系统结垢附着速度和腐蚀速度大大低于国家标准,对运行水质没有明显影响。
3.
Because of changes of environment and water supply capacity for water circulation system of power plant,makes it need of technology reform to solve the conflict between water supply and consumption,and it can reduce the energy consumption of water circulation system,increase the set s thermal efficiency,and save energy.
本文主要介绍了电厂循环水系统在取水环境和供水容量等方面进行改造,通过技术改造既解决了水量的供需矛盾,又大大降低了循环水系统的能量消耗,提高了机组的热效率,节约了能源。
5) water circulating system
水循环系统
1.
Water-supply and water-treatment practice of water circulating system for underground equipments
井下大型设备水循环系统给水及水处理方法实践
2.
With the assist of online monitoring system,TS-223A was applied in the water circulating system in the ethylene plant of Tianjin Petrochemical Corporation, the adhesion rate was less than 15 mg/cm2 a month, corrosion rate was under 0.
配合自控装置和计算机远程控制平台,将TS-223A应用于天津石化公司乙烯厂第一循环水场水循环系统,每月黏附速率≤15 mg/cm2,腐蚀速率≤0。
3.
Using the arithmetic of interveined gridding dispersing may better resolve the influence of the compressibility and heat dilatability of liquid on the arithmetic of water circulating system, and will supply the .
采用交错网格离散化算法较好地解决了流体的压缩性和热膨胀性对循环系统算法的影响,为锅炉水循环系统的数值模拟和设计提供重要参数。
6) circulation water system
循环水系统
1.
The precipitation bailing planning of circulation water system construction of Wangtan electric power plant
王滩电厂循环水系统施工降排水方案
2.
There were some problems in the circulation water system for continuous casting of square billet of Jiuquan Iron & Steel Co.
针对酒钢方坯连铸循环水系统存在的水量不平衡、水温超标及水质超标等问题,分析了产生问题的原因,论述了改进措施及效果。
3.
When a transient hydraulic change occurs to the circulation water system of a thermal power plant, the condenser may be subjected to a loss of cooling water, leading to an increase of operating pressure of the condenser, and thereby affecting the operating stability and safety of a steam turbine unit.
这样既能保证循环水系统的水力安全,又考虑了瞬变过程中凝汽器的动态特性,有利于汽轮机组的安全稳定运行。
补充资料:阀门技术注重流量系数和气蚀系数
阀门的流量系数和气蚀系数是阀的重要参数,这在先进工业国家生产的阀门资料中一般均能提供。我国生产的阀门基本上没有这方面资料,因为取得这方面的资料需要做实验才能提出,这是我国和世界先进水平的阀门差距的重要表现之一。
3.1、阀门的流量系数
3.1、阀门的流量系数
阀门的流量系数是衡量阀门流通能力的指标,流量系数值越大,说明流体流过阀门时的压力损失越小。
按KV值计算式
式中:KV—流量系数
Q—体积流量m3/h
ΔP—阀门的压力损失bar
P—流体密度kg/m3
3.2、阀门的气蚀系数
用气蚀系数δ值,来选定用作控制流量时,选择什么样的阀门结构型式。
式中:H1—阀后(出口)压
H2—大气压与其温度相对应的饱和蒸气压力之差m
ΔP—阀门前后的压差m
各种阀门由于构造不同,因此,允许的气蚀系数δ也不同。如图所示。如计算的气蚀系数大于容许气蚀系数,则说明可用,不会发生气蚀。如蝶阀容许气蚀系数为2.5,则:
如δ>2.5,则不会发生气蚀。
当2.5>δ>1.5时,会发生轻微气蚀。
δ<1.5时,产生振动。
δ<0.5的情况继续使用时,则会损伤阀门和下游配管。
阀门的基本特性曲线和操作特性曲线,对阀门在什么时候发生气蚀是看不出来的,更指不出来在那个点上达到操作极限。通过上述计算则一目了然。所以产生气蚀,是因为液体加速流动过程中通过一段渐缩断面时,部分液体气化,产生的气泡随后在阀后开阔断面炸裂,其表现有三:
(1)发生噪声
(2)振动(严重时可造成基础和相关构筑物的破坏,产生疲劳断裂)
(3)对材料的破坏(对阀体和管道产生侵蚀)
再从上述计算中,不难看出产生气蚀和阀后压强H1有极大关系,加大H1显然会使情况改变,改善方法:
a.把阀门安装在管道较低点。
b.在阀门后管道上装孔板增加阻力。
c.阀门出口开放,直接蓄水池,使气泡炸裂的空间增大,气蚀减小。
综合上述四个方面的分析、探讨,归纳起来对闸阀、蝶阀主要特点和参数列表便于选用。两个重要参数在阀门运用中 。
说明:补充资料仅用于学习参考,请勿用于其它任何用途。
参考词条