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整体式热流道热嘴易断裂问题探讨
Discussion on the Problem of Breakable Nozzle of Integral Hot Runner
 [PDF]

王焕, 张茜, 钟少基, 黄诗君
Mechanical Engineering and Technology (MET) , 2015, DOI: 10.12677/MET.2015.44030
Abstract:
热流道中热嘴断裂严重影响了整体式热流道的使用寿命,制约了热流道技术在模具中的推广和应用,为了解决断裂问题,本文就此展开讨论。结合热嘴自身结构和使用环境因素综合考虑,归纳出四个主要因数:螺纹连接的缺陷、温度的影响、针阀冲击、注射压力,同时对每一种影响因数进行了详细的计算。针对断裂现象提出了三种改进方案。改进后的热流道系统断裂现象明显减少,极大地提高了系统的可靠性和使用寿命。
Nozzle fracture of hot runner severely affects the overall service life of hot runner, restricting the promotion and application of hot runner technology in the mold. In this paper, we discussed the fracture problem in order to solve it. Taking into account the structure and use environment of the nozzle, four main factors of the fracture problem were summarized: threaded connection defect, temperature effect, needle valve shock, and injection pressure. And then each impact factor was calculated in detail. Aiming at the fracture, three improvement projects were also proposed. Frac-ture had been reduced significantly in the improved hot runner system, greatly enhancing the re-liability and service life.
FRACTURE FAILURE ANALYSIS OF FIRE EXTINGUISHER NOZZLE FOR Y-5 AIRCRAFT
运五飞机灭火瓶管嘴断裂的失效分析

WANG Zai-jun,LIU Xian-chao,
王在俊
,刘显超

腐蚀科学与防护技术 , 2007,
Abstract: The fractograph,chemical composition and microstructure of the failed extinguisher nozzle were analyzed by SEM and energy spectrum. The result shows that the fracture of the fire extinguisher is caused by the tensile stress and atmospheric corrosion. To prevent the nozzle failure, some improved measures are suggested in the paper.
喉嘴距对喷射器性能影响的实验研究
Experimental investigation of influences of primary nozzle exit position on ejector performance
 [PDF]

陈伟雄,陈会强,石朝胤,王迎春,种道彤,严俊杰
- , 2016, DOI: 10.7523/j.issn.2095-6134.2016.02.017
Abstract: 摘要 喉嘴距是影响喷射器性能的重要结构参数,研究其对喷射器性能的影响对提升喷射器性能有重要意义.本文对喷射器性能进行实验研究,获得不同喉嘴距和运行工况参数下,喷射器性能的变化规律.研究发现:在本实验范围内,喉嘴距对喷射器的临界背压值影响较小,对喷射器引射比影响较大,引射比随喉嘴距的增大先增大后减小.喷射器单相运行时和两相运行时均存在一个最优喉嘴距,最优喉嘴距随低压流体含液量的增大而增大.当喷射器单相运行时,最优喉嘴距为2.8 mm,当低压流体含水量达到0.07 kg/min时,最优喉嘴距为3.6 mm.
孕穗期叶面喷素对小麦穗粒数和粒重的影响  [PDF]
田艳云,张国钊,郑春风,段建钊,秦一凡,朱云集,,,杨家蘅
- , 2016, DOI: 10.7606/j.issn.1009-1041.2016.07.13
Abstract: 为探讨孕穗期叶面喷素对小麦穗粒数和粒重的调控效应,于2014-2015年在河南农业大学科教示范园区进行试验,以半冬性品种豫麦49-198 为供试材料,在小麦拔节后25 d(4月6号),以清水为对照,叶面分别喷施硼砂(B)、6苄基腺嘌呤(6-BA)、6-BA+B、奇善宝(QSB)、双增1号(CPD),对不同喷素条件下小花败育速率和籽粒灌浆进程及其成熟后小麦穗部性状进行观察和分析。结果表明,与对照相比,不同喷素处理均能降低小花的败育速率,显著增加小麦不同部位的小穗粒数和粒重。对小麦各部位小穗粒数的促进效果,以CPD处理对小麦下、中部小穗粒数提高幅度最大,分别较对照增加了1.95个和4.85个;对不同部位小穗粒重的促进效果,也以CPD处理效果最佳,使小麦下、中和上部小穗粒重分别较对照提高了11.97%、5.87% 和9.32%。
响蜜Lie科的新记录
杨岚
动物学研究 , 1995,
Abstract: 1994年10月15日马中翼等人在云南省泸水县的老窝捕获到1只雄鸟,经中国科学院昆明动物研究所鉴定为黄腰响蜜lie,为我国鸟类科的新记录。标本保存在中国科学院昆明动物研究所鸟类标本室。科的特征体形较小。嘴形似雀,短而粗实,上嘴稍弯曲;尾羽12枚;翅形长而尖,仅具9枚初级飞羽;脚呈对趾型,第2、3趾向前,第1、4趾向后,似啄木鸟。
响蜜lie科的新记录  [PDF]
动物学研究 , 1995,
Abstract: 1994年10月15日马中翼等人在云南省泸水县的老窝捕获到1只雄鸟,经中国科学院昆明动物研究所鉴定为黄腰响蜜lie,为我国鸟类科的新记录。标本保存在中国科学院昆明动物研究所鸟类标本室。科的特征体形较小。嘴形似雀,短而粗实,上嘴稍弯曲;尾羽12枚;翅形长而尖,仅具9枚初级飞羽;脚呈对趾型,第2、3趾向前,第1、4趾向后,似啄木鸟。
空化水喷丸工艺中喷嘴几何参数对空化行为影响的研究
Influence of Nozzle Geometric Parameter on Cavitation Behavior in Water-jet Cavitation Peening Processing
 [PDF]

韩冰,赵刚,王梓卉敏
- , 2016,
Abstract: 空化水喷丸是利用微小空泡群在固体边界附近溃灭时产生的冲击波压力和微射流来强化金属材料表面,而这些空泡群则是由缩放型喷嘴产生的空化射流所提供。因此,缩放型喷嘴的空化性能可直接影响喷丸效果。利用FLUENT计算软件对缩放型喷嘴产生的淹没式空化水射流进行计算机模拟,并模拟分析了喷嘴喉部直径和喷嘴扩张角对流场中空化行为的影响,同时使用Fujifilm压敏试纸对垂直于空化水射流轴线的截面上的冲击压力场进行测量。结果表明,随着喷嘴喉部直径的增大或喷嘴扩张角的减小,流场中的整体汽含率会升高,试验测得的最高冲击压力高达300 MPa。
Water-jet cavitation peening uses the shock wave pressure and micro-jet produced by the cavitation bubbles collapsing near the surface of materials to strengthen the material surface, the cavitation bubbles are provided by the submerged cavitating water jet generated by convergent-divergent nozzle. Therefore, the cavitation capability of convergent-divergent nozzle can affect the peening effect directly. With using FLUENT software,the computer simulation is applied to study the submerged cavitating water jets, and the influences of nozzle throat diameter and nozzle divergence angle on the cavitation behavior in the flow field are analyzed. The Fujifilm pressure-sensitive paper is applied to measure the pressure distribution on the section which is perpendicular to the axis of cavitating water jet. The results show that the vapor fraction in flow field rises with the nozzle throat diameter increasing or the nozzle divergence angle decreasing, and the measured pressure in the experiment is up to 300 MPa
喷嘴数和温比对旋流冷却流动和传热特性的影响
Effects of Nozzle Numbers and Temperature Ratios on Flow and Heat Transfer Characteristics of Vortex Cooling
 [PDF]

范小军,邹佳生,周源远,李亮
- , 2018, DOI: 10.7652/xjtuxb201803003
Abstract: 针对喷嘴数和温比对叶片前缘旋流冷却特性影响的问题,根据实际燃气轮机前缘结构进一步完善了旋流冷却模型,建立了含有进气腔室的旋流腔结构,采用数值模拟方法分析了喷嘴数和温比对旋流冷却特性的影响。研究时保持进口雷诺数和靶面温度不变,仅改变喷嘴数和温比。研究结果表明:进气腔室的引入使得喷嘴冷气沿流动方向逐渐增加。随着喷嘴数增加,喷嘴冷气流速降低,压力系数增加,流阻系数减小,换热强度降低但均匀性提高,综合换热因子增大。随着温比增加,喷嘴冷气流速增加,流阻系数减小,靶面热流密度降低,换热强度提高,综合换热因子增大。对于含有进气腔的叶片前缘冷却结构,推荐选取喷嘴数为6,温比范围为0.6~0.7。
Aiming at the influences of the number of nozzles and temperature ratio on vortex cooling characteristics of gas turbine blade leading edge, a coolant chamber was added to establish a more reasonable vortex cooling configuration. Numerical method was used to investigate the flow and heat transfer behavior. The inlet Reynolds number and target temperature remained constant while the number of nozzles and temperature ratio were changed in the research. Results showed that the mass flow of air from nozzles increases along the flow direction with the introduction of coolant chamber. As the number of nozzles increases, the velocity of nozzle air, the friction coefficient and the heat transfer intensity decrease while the pressure coefficient, the uniformity of heat transfer intensity distribution and the thermal performance factor increase. As temperature ratio increases, the velocity of air from nozzles, the heat transfer intensity and the thermal performance factor increase, while the friction coefficient and the target heat flux decrease. For the gas turbine blade leading edge with the coolant chamber, the number of nozzles N=6 and the temperature ratio 0.6??0.7 are recommended
激波诱导推力矢量喷管不同气体喷注时的性能分析
Performance analysis of shock thrust vector nozzle under different gas injections
 [PDF]

王晓明,刘辉,韩龙柱,袁修干
- , 2018, DOI: 10.13700/j.bh.1001-5965.2018.0161
Abstract: 摘要 针对激波诱导推力矢量控制研究仅限于主流和次流气体为同种气体的研究现状,开展了不同次流气体分子质量对推力矢量性能的影响规律研究。首先采用二阶精度AUSM+格式和k-ω SST两方程湍流模型求解三维Favre平均Navier-Stokes方程,模拟了喷管复杂干扰内流场。然后计算了He、N2和CO2等次流气体在不同注气角度、注气压力和主流落压比下的矢量偏转角度和推力系数。计算结果表明:平均分子质量越小的次流气体矢量偏转角度越大,推力损失越小。因此可选用平均分子质量小的气体作为次流气源,或者将从燃烧室引出的高温燃气与分子质量小的气体混合。
Abstract:Aimed at the research status of the shock thrust vector control, which is limited to the mainstream and secondary flow gas as the same gas, the influence of different secondary flow gas molecular mass on thrust vector performance is investigated. First, a turbulence model described by two equations (AUSM+ scheme and k-ω SST) at two-order accuracy was utilized to solve the Favre averaged three-dimensional Navier-Stokes equations, which simulated the complex interference inner flow field of the nozzle, and the vectorial deflection angles and thrust coefficients were calculated under different gas injection angles, injection pressures and nozzle pressure ratios when the secondary flow gas of He, N2 and CO2 were selected. The calculation results show that the smaller the mean molecular mass of the secondary flow gas is, the larger the vectorial deflection angle is, the less the thrust loss is. Therefore, the gas with smaller mean molecular mass could be used as the gas source of the secondary flow, or the high temperature gas derived from the combustion chamber could be mixed with the gas with a smaller mean molecular mass.
大嘴乌鸦繁殖生态的初步研究  [PDF]
任建强,高建新,安文山,胡玉娥,薛恩祥,杨向明,郝映红
动物学杂志 , 1995,
Abstract: 本文为大嘴乌鸦繁殖生态的研究报告。研究内容主要有大嘴乌鸦的栖息生境,数量统计,繁殖习性。观察得知大嘴乌鸦5月上旬产卵,窝卵数3-6枚,大小平均34.9×36.9毫米,卵重平均15.3克,孵化期15-16.5天,育雏期27-31天。
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