High strain rate fragmentation of liquid systems at atmospheric pressure

The fragmentation characteristics of liquid systems at atmospheric pressure has been investigated experimentally and compared to hydrodynamic calculations as well as theoretical predictions. The geometry is a one-dimensional (1-D) nylon flat plate impacting a flat plate liquid system at velocities of approximately 0.3 km/s. The experiments were conducted at the Marquette University's gas gun facility. Hydrocodes calculations were used to investigate early time shock evolution, material deformation and strain rate. High-speed photography and witness cards were used to capture the impact and fragmentation event as well as drop distributions. The experimental drop distributions are compared to distributions obtained from a Grady–Kipp (GK) fragmentation model. The liquid spall GK fragmentation model predicted the correct median drop size while the flow stress spall over predicted the median drop size. The standard GK Poisson drop distribution superimposed over the median drop size produces a distribution which is wider than the data obtained.     

A1－Cu合金液态过热处理的研究

对二元Ａｌ－１０ｗｔ％Ｃｕ亚共晶和Ａｌ－３３．２ｗｔ％Ｃｕ共晶合金液态进行７００～１２００℃范围过热处理，然后在粘土砂型和金属型中凝固。试验研究了液态过热对固态显微组织、显微硬度、宏观晶粒大小及凝固过程特征温度的影响，分析了Ａｌ－Ｃｕ合金的液态结构。     

液态金属电阻率测定装置及应用

概括述评了液态金属电阻率测定方法，建立了直流恒流四电极法测试液态金属电阻率的系统装置，并利用该方法对高铝液态电阻率进行了测定，验证了该系统装置测试的可靠性。     

下塔液空液位异常的原因及处理

对液空吸附器损坏造成下塔液空液位异常的故障原因进行分析 ,提出了解决措施。     

新型液氧水浴式汽化器的开发与应用

为解决宣钢现有液氧汽化系统中液氧水浴式汽化器振动较大的问题,改变液氧水浴式汽化器中蒸汽与循环水的换热形式,开发了一种新型水浴式汽化器,获得了很好的使用效果。     

基于液滴指纹图波形分析的液体识别方法

为了定量地描述“光电液滴指纹图”鉴别液体的功能,提出一种波形分析法来提取指纹图的特征参数。采用“邻域比较法”或“基于最大值和最小值的极值检测法”确定指纹图的峰谷位置,分别计算表征主峰、次峰和波谷的电容信号和光纤信号的参数,以及指纹图的曲线长度和曲线面积。实验证明,“曲线面积”是最有效的识别参数,不同种类液体的相对分辨率为7.45%;同一种类不同品牌的水、饮料、酒、醋和酱油的相对分辨率分别为1.96%,7.64%,14.39%,0.07%和3.65%。指纹图的“次峰”是相对较弱的特征,相对分辨率仅为0.07%。     

Design of multi-scale textured surfaces for unconventional liquid harnessing

The ability to manipulate liquids in a loss-free and refined manner has long been anticipated, with applications in fields such as analytical chemistry, medical diagnosis, and droplet-based manufacturing. The challenge derives from the liquid/solid contacts, which incur spontaneous spreading, strong pinning, and substantial retention. The retention-proof interfaces, including superhydrophobic surfaces, lubricant-infused surfaces, and liquid marbles, mitigate these issues by respectively introducing air, lubricant, and particulate layers to isolate liquids from underlying solids. Assisted by these interfaces, contrastive physical/chemical designs and engineering methods are leveraged to unlock unparalleled liquid-control methods that are otherwise inaccessible. In this review, we focus on the application of retention-proof interfaces in three facets of manipulation: the aliquoting, grip, and transport of fluids. We discuss the key features, strategies and implementations, highlighting the fundamental physics and operation principles. For aliquoting, the cooperation between diminutive geometries and interfaces in partition droplets are examined. For the grip, we discuss the impact of micro-/nanotextures on adhesion behavior and highlight the mechanisms of switching the adhesive forces. For the transport, we review various engineering and functionalizing forms through which subtle driving forces are dexterously imposed on mobile droplets. The performance of different techniques is evaluated, and potential directions are proposed.     

缩短KDON-400/1000型空分设备启动时间的操作

介绍了为缩短KDON-400/1000型空分设备启动时间而采取的改进操作;实施后,空分设备的启动时间由24~36h缩短到6~8h,保证了后续生产的正常用氧;最后提出了改进操作时需注意的事项。     

Bistable cholesteric-blue phase liquid crystal using thermal hysteresis

The study investigates the thermal hysteresis in the phase transition between the cholesteric liquid crystal and the blue phase of liquid crystal. Both the CLC phase and the blue phase can stably exist at room temperature and be switched to each other using temperature-controlled processes. Two sets of bistable conditions are demonstrated using various surface treatments. In a homogeneous aligned sample, two stable states, CLC with a planar alignment and blue phase with a uniform lattice distribution, reflect light of wavelengths 480-510 nm and 630 nm, respectively, as determined by the corresponding Bragg’s reflection conditions. In the untreated sample, the CLC phase with a focal conic texture can scatter light and the blue phase with a non-uniform lattice distribution provides high isotropic optical transparency.     

Statistics of Capillary Waves on the Surface of Liquid Hydrogen in a Turbulent Regime

Excitation of the surface of liquid hydrogen by a harmonic force at low frequencies leads to the formation of turbulent cascade in the system of capillary waves. We have found that the probability density function for a high-frequency surface deviation from equilibrium state in the regime of developed turbulence is well approximated by the Gaussian distribution.      

Characterisation and optimisation of flexible transfer lines for liquid helium. Part I: Experimental results

The transfer of liquid helium (LHe) into mobile dewars or transport vessels is a common and unavoidable process at LHe decant stations. During this transfer reasonable amounts of LHe evaporate due to heat leak and pressure drop. Thus generated helium gas needs to be collected and reliquefied which requires a huge amount of electrical energy. Therefore, the design of transfer lines used at LHe decant stations has been optimised to establish a LHe transfer with minor evaporation losses which increases the overall efficiency and capacity of LHe decant stations. This paper presents the experimental results achieved during the thermohydraulic optimisation of a flexible LHe transfer line. An extensive measurement campaign with a set of dedicated transfer lines equipped with pressure and temperature sensors led to unique experimental data of this specific transfer process. The experimental results cover the heat leak, the pressure drop, the transfer rate, the outlet quality, and the cool-down and warm-up behaviour of the examined transfer lines. Based on the obtained results the design of the considered flexible transfer line has been optimised, featuring reduced heat leak and pressure drop.