几种喷头的布水性能对比试验

开发了具有自主知识产权的玻璃防火分隔专用喷头。通过对自行研制的专用喷头与WS窗玻璃喷头及国内普通侧喷喷头的冷态布水情况开展对比试验,对在不同压力、与玻璃之间不同安装距离的情况下,3种喷头在玻璃上的布水喷洒、水在玻璃上的分布情况、流量系数K值等进行对比分析研究。结果表明,自行研制的玻璃防火分隔专用喷头的喷洒效果显著,能达到甚至超过WS窗玻璃喷头的喷洒效果,而普通侧喷喷头的喷洒效果最差。

高大空间场所自动喷水灭火系统布水性能试验研究

为研究工作压力、安装高度等对喷头布水性能的影响,以K161喷头为研究对象,在安装高度分别为8m、12m和18m,工作压力分别为0.05MPa、0.10MPa、0.15MPa和0.20MPa的条件下,共计开展了12次喷头布水性能试验。试验结果显示,喷头集水率受安装高度的影响较小,在相同工作压力下,12m和18m高度下实测喷水强度基本一致,但随着工作压力的增加,喷头集水率逐渐增加,与理论计算值趋于一致,但均小于理论计算值;工作压力越高,喷头布水均匀性越差。

信息熵在人工湿地布水性能评价中的应用探析

研究了信息熵应用于垂直流人工湿地布水性能评价中的可行性。结果表明:其评价结果不受时间和单次布水总量的影响,能有效将布水面积与基质底部各位置接水量的均匀性结合起来,评价结果更具有实际意义。对于单一粒径5~10 mm、连通孔隙率25.3%~32.9%的粘结型模块化基质而言,布水性能随布水管单孔进水流量的增大而提高得越来越慢,运行初期布水管单孔最佳进水流量为600 mL/min;布水性能随基质深度的增加而提高,在深度为70 cm以后布水性能提高不再明显。

喷头的布水性能还是提出均匀度指标好——对GB5135的补充意见

众所周知,无论是洒水喷头还是泡沫喷头,在它的整个保护面积内的介质密度分布都不是绝对均匀的。为了描述喷头的喷洒特性,人们采用了介质分布曲线或分布图,其中最普遍采用的是以喷射半径R为横座标,以沿喷射半径方向上集水盒的接水深度h为纵座标,或以沿喷射半径方向上喷头喷射到单位面积上的介质量,即喷洒强度P为纵座标。

高吸水性非织造布的研制

介绍了合成聚丙烯酸接枝淀粉浆液并使其在非织造布上形成吸水树脂 ,从而得到高吸水性非织造布的实验过程 ,对接枝单体的比例、交联条件、浸轧量及非织造布本身材质等因素对吸水非织造布吸水性能的影响进行了讨论。

新型火冰灭火剂喷洒布水性研究

通过实验数据阐述新型火冰灭火剂在自动喷水灭火系统中的喷洒布水性能。对比水、A型火冰灭火剂、AB型火冰灭火剂的喷洒质量分布情况,得出:AB型火冰灭火剂与水相近,可直接用于自动喷水灭火系统或水-泡沫灭火两用系统中;A型火冰灭火剂则不可直接使用。

微波技术制备吸水性无纺布

讨论了微波加热的基本原理及影响因素,研究了微波法制备缠绕着丙烯酸交联物的吸水性无纺布的生产工艺,讨论了AA浓度、引发剂用量、辐射时间、交联剂用量诸因素对无纺布相对吸水率的影响。通过正交实验得出最佳工艺条件及配方:微波功率485W,微波辐射时间30s,AA浓度35％,引发剂与单体摩尔比为0.05,交联剂用量为0.3％。与常规法相比,微波加热法优于常规加热法。

土工布透水性测定仪校准方法与影响分析

介绍了土工布透水性测定仪的工作原理和用途,建立了土工布透水性测定仪校准结果的测量模型,分析了各不确定度分量主要来源,结合测量实例具体数据,对其合成不确定度进行分析评定,对各不确定度分量进行计算并得出合成不确定度和扩展不确定度,最终可得出该项目的校准测量能力,为纺织行业提供的技术支撑。

间接蒸发冷却器高效换热材料亲水和布水研究

研究间接蒸发冷却器高效换热材料的亲水性与布水均匀性。采用测试接触角、喷雾布水、喷淋布水等方法,分别对聚丙烯高分子材料、金属铝箔材料、植物纤维聚合物材料的亲水性和布水性进行对比分析。结果表明:材料亲水性较优顺序依次为植物纤维聚合物材料、金属铝箔材料、聚丙烯高分子材料。喷嘴布水均匀应该控制的喷雾布水时间:聚丙烯高分子材料,02^(#)、03^(#)喷嘴布水时间120 s~300 s,05^(#)喷嘴布水时间30 s~120 s;金属铝箔材料,02^(#)喷嘴布水时间120 s~300 s,03^(#)、05^(#)喷嘴布水时间30 s~120 s;植物纤维聚合物材料,02^(#)喷嘴布水时间120 s~300 s,03^(#)喷嘴布水时间30 s~120 s。认为:间接蒸发冷却器高效换热材料宜采用亲水性较好的植物纤维聚合物材料和03^(#)喷嘴,喷雾布水时间30 s~120 s;采用喷淋布水时,适当增加喷水量,可使布水更加均匀。

闭式旋转型雨淋喷头的试验研究

介绍闭式旋转型雨淋喷头的结构和工作原理。通过动态热性能试验验证闭式旋转型雨淋喷头玻璃球热反应灵敏度,进行了下垂安装方式两个高度的布水性能试验,通过木垛火灭火试验和不同工作压力的转速试验检验其灭火控制性能,并在0.2 MPa的工作压力下试验连续喷水性能。试验结果表明:闭式旋转型雨淋喷头结构设计利于热传递,具有良好的动态热性能和布水均匀性,且达到轻危险级洒水密度要求,工作稳定可靠。

Drainage performance and capillary rise restraint effect of wicking geotextile

Wicking geotextile(WG)is considered as a possible countermeasure to reduce water content in unsaturated soil.In this research,rainfall tests were carried out to verify the drainage performance of WG.And capillary rise tests were conducted to study the effect of WG on the prevention of capillary rise.Test results indicated that WG with good drainage performance could drain gravitational and capillary water out of kaolinite soil.For kaolinite soil column with water content of 12%and compaction degree of 90%,the whole process of capillary rise in soil column with a layer of WG was a typical two-stage mode,and the maximum capillary height was about 380 mm,which provided that the WG could work as a barrier to prevent capillary rise effectively.In addition,the total vertical influential regions of WG in kaolinite soil above and below the WG layer were 400 and 100 mm,respectively.

Physical properties and filter cake structure of fine clean coal from flotation

In order to improve the dewatering rate and the effect of fine clean coal(FCC), the advanced method offine coal( 0.5 mm) dewatering and the correlated basic theory were investigated in this study. It was found that the dewatering by sleeve type press filter was an efficient way of FCC dewatering. On the other hand, the results also proved that particle size distribution, volatile matter, ash content, pore size distribution and specific surface area of coal particles of FCC samples, as well as viscosity and density of FCC slurry, were important parameters in determining the process of efficient dewatering. Especially, wet mass to dry mass, specific resistance of average mass, compressibility factor and microstructure of filter cake explained the reasons and mechanisms of fine clean coal efficient dewatering.

用于PP非织造织物的纤维亲水整理剂

介绍了英国Uniqema公司研制的CirrasolPP 842和CirrasolPP 82 2纤维亲水整理剂。这是能使织物快速、反复传递水分和其他液体的高效芯吸剂 ,可用于尿布、妇女卫生用品等包覆材料的整理。

Study of Vertical Breakwater Reliability Based on Copulas

The reliability of a vertical breakwater is calculated using direct integration methods based on joint density functions.The horizontal and uplifting wave forces on the vertical breakwater can be well fitted by the lognormal and the Gumbel distributions,respectively.The joint distribution of the horizontal and uplifting wave forces is analyzed using different probabilistic distributions,including the bivariate logistic Gumbel distribution,the bivariate lognormal distribution,and three bivariate Archimedean copulas functions constructed with different marginal distributions simultaneously.We use the fully nested copulas to construct multivariate distributions taking into account related variables.Different goodness fitting tests are carried out to determine the best bivariate copula model for wave forces on a vertical breakwater.We show that a bivariate model constructed by Frank copula gives the best reliability analysis,using marginal distributions of Gumbel and lognormal to account for uplifting pressure and horizontal wave force on a vertical breakwater,respectively.The results show that failure probability of the vertical breakwater calculated by multivariate density function is comparable to those by the Joint Committee on Structural Safety methods.As copulas are suitable for constructing a bivariate or multivariate joint distribution,they have great potential in reliability analysis for other coastal structures.

Investigation on Water Jet Treated Polyester/cotton Blended Cambric

Analytical examination was made to ascertain the effect of the high pressure water flow on the fabric properties.Polyester/cotton blended cambric was spurted by high pressure water flow. Fabric properties such as handle,thickness, tensile strength , stiffness and air permeability after the water treatment were investigated.

Contrastive Analysis of Cooling Performance between a High-level Water Col-lecting Cooling Tower and a Typical Cooling Tower

A three-dimensional （3D） numerical model is established and validated for cooling performance optimization between a high-level water collecting natural draft wet cooling tower （HNDWCT） and a usual natural draft wet cooling tower （UNDWCT） under the actual operation condition at Wanzhou power plant, Chongqing, China. User defined functions （UDFs） of source terms are composed and loaded into the spray, fill and rain zones. Consider- ing the conditions of impact on three kinds of corrugated fills （Double-oblique wave, Two-way wave and S wave） and four kinds of fill height （1.25 m, 1.5 m, 1.75 m and 2 In）, numerical simulation of cooling performance are analysed. The results demonstrate that the S wave has the highest cooling efficiency in three fills for both towers, indicating that fill characteristics arc crucial to cooling performance. Moreover, the cooling performance of the HNDWCT is far superior to that of the UNDWCT with fill height increases of 1.75 m and above, because the air mass flow rate in the fill zone of the HNDWCT improves more than that in the UNDWCT, as a result of the rain zone resistance declining sharply for the HNDWCT. In addition, the mass and heat transfer capacity of the HNDWCT is better in the tower centre zone than in the outer zone near the tower wall under a uniform fill layout. This behaviour is inverted for the UNDWCT, perhaps because the high-level collection devices play the role of flow guiding in the inner zone. Therefore, when non-uniform fill layout optimization is applied to the HNDWCT, the inner zone increases in height from 1.75 m to 2 m, the outer zone reduces in height from 1.75 m to 1.5 m, and the outlet water temperature declines approximately 0.4 K compared to that of the uniform layout.