Numerical Simulation of Shaped Charge Jet Using Multi-Phase SPH Method

Since the jets and detonation gaseous products are separated by sharp interfaces, the traditional smoothed particle hydrodynamics (SPH) method is difficult to avoid the computational instability at interfaces. The multi-phase SPH (MSPH) method was applied to improving the stabil-ity, which smoothes the particle density and makes pressure continuous at interfaces. Numericalexamples of jet forming process were used to test capability of the MSPH method. The results show that the method remains algorithm stability for large density gradient between the jets and gaseous products and has potential application to both the explosion and the jet problems. The effect of initiation ways of the shaped charge was discussed as well.     

Heat Transfer of an Array of Round Impinging Jets with One-Sided Exhaust of the Spent Air

ＨｅａｔＴｒａｎｓｆｅｒｏｆａｎＡｒａｙｏｆＲｏｕｎｄＩｍｐｉｎｇｉｎｇＪｅｔｓｗｉｔｈＯｎｅＳｉｄｅｄＥｘｈａｕｓｔｏｆｔｈｅＳｐｅｎｔＡｉｒＳｏｎｇＹｉｊｕｎ（宋益军）ＣｈｅｎＹｏｎｇｙｕａｎ（程永元）ＣａｉＳｏｎｇ（蔡崧）（Ｔｈｅｒｍｏｅｎｅ...     

Large eddy simulation of a particle-laden turbulent plane jet

Gas-solid two-phase turbulent plane jet is applied to many natural situations and in engineering systems. To predict the particle dispersion in the gas jet is of great importance in industrial applications and in the designing of engineering systems. A large eddy simulation of the two-phase plane jet was conducted to investigate the particle dispersion patterns. The particles with Stokes numbers equal to 0.0028, 0.3, 2.5, 28 (corresponding to particle diameter 1 μm, 10μm, 30μm, 100μm, respectively) inRe=11 300 gas flow were studied. The simulation results of gas phase motion agreed well with previous experimental results. And the simulation results of the solid particles motion showed that particles with different Stokes number have different spatial dispersion; and that particles with intermediate Stokes number have the largest dispersion ratio. Project (No. G19990222) supported by the Special Funds for Major State Basic Research of China     

活性硫对喷气燃料银片腐蚀影响的研究

考察了硫化氢、元素硫、硫醇、硫醚、多硫化物等单独存在时对喷气燃料银片腐蚀的影响；同时考察了元素硫与其它硫化物以不同浓度混合时对喷气燃料银片腐蚀的影响。试验结果表明，硫化氢、元素硫是导致喷气燃料银片腐蚀不合格的主要原因。当元素硫和硫化氢单独存在时，元素硫的浓度只要大于0．5μg／g硫化氢的浓度只要大于1．5μg/g，喷气燃料银片腐蚀就不合格。当与其它硫化物共存时，其它硫化物只起着协同的作用。     

下喷自吸环流反应器内液相局部流动特性

对下喷自吸环流反应器内气－液两相流和气－液－团三相流体系的液相局部流动特性进行了实验研究．用改进皮托管对液相瞬时速度进行了测量，并借助湍流统计理论对渡相平均速度、液相湍动速度和湍动微尺度等液相局部流动参数进行了统计分析和处理，着重讨论了喷射液体流量和固体粒子加入量分别对喷射有效区和导流筒内管流区液相局部流动参数的影响．     

Research on disturbance properties of suspensions near the injection area of moving jet

The equation of the suspension-gas non-streamwise complex disturbance velocity ratio near the injection area of moving jet was theoretically derived by using a phase-coupled model and stability theory. Then the ratio curves were obtained by the finite difference method based on the asymptotic method and the Euler conservative difference scheme. Analysis of the curves yielded conclusions on the disturbance properties of suspensions and effects of the natures of the flow-field and the properties of the suspensions on the suspensions ability to track the disturbed gas flow are presented in this paper. Projects supported by the State Education Commussion’s Trans-century Training Program Fund for Talents     

Experiments on Deflecting & Oscillating Waterjet

A new type jet, the oscillating & deflecting jet, is put forward and its oscillating and deflecting characteristics are investigated. The nozzle of the self-oscillating & deflecting water jet consists of an upstream nozzle, a downstream nozzle, an oscillating chamber and two switches. It is experimentally shown that the deflective angle may reach 9.53 degree. The generated pressure fluctuation is very regular and the jet can efficiently increase the ability for breaking and cutting by eliminating the water cushion effect associated with a continuous jet.     

圆柱射流截面形状的周向变化对界面不稳定性的影响

This paper concentrated on the effect of azimuthal variation of section shape on the instability of a cylindrical jet.A single fluid model under certain assumptions was constructed.The characteristic relation between frequency and wave number is obtained using the normal-mode method.The effect of some parameters on the stability was examined and some phenomena in experiments were explained.     

深基坑侧壁的分层、刚柔支护结构分析

提出了一套全新的支护深基坑侧壁的方法,即分层、刚柔支护方法.给出了分层、刚柔支护结构的理论计算方法,并将该方法与传统的支护方法作了全面的技术对比分析。     

气流粉碎机渐缩型喷嘴关键参数的研究

介绍了气流磨的特点,重点研究了渐缩型喷嘴设计的主要参数,对喷嘴的喷气速度、工质流量及喷嘴几何参数进行了研究,得到了喷嘴设计过程中的关键参数对粉碎性能的影响,为进一步将气流粉碎应用到煤炭提供了依据。