The spontaneous formation of inhomogeneity in a classical one-particle “gas”: An example in silico

A single classical isoergic particle was placed in a cube and allowed to propagate for 100 ns to 10 ms. The interaction of the particle with the inner wall of the cube was modeled as a linear combination of specular and random reflection, the extent of the combination being governed by a user-defined “roughness” parameter α. As a function of α, the particle’s relative pressure and density spontaneously took on an inhomogenous distribution.     

一种富于启发性的热机实验演示与分析

利用试管、玻璃球、器、圆盘等易取材料研制了使玻璃球通过重力作用原理来转移工作物质的方法，并可用燃烧热、电阻热和光转化热作为高温热源的动力的热机实验演示，同时我们给出了相应的理论分析。     

热机的第二定律效率与不可逆性

利用热机的功－熵关系和可用能概念，给出热机经二定律效率的表达式，同时了热机相对损失功的概念，并用它们比较了几个实际动力源的不可逆程度。     

模糊控制器用于改善涡轮增压柴油机的部分负荷性能

模糊控制已在一类缓变的过程控制中得到成功的应用,本文将它引入到柴油机这一高速系统的性能控制,研究了相应的模糊控制器的设计方法,研制了以微计算机为核心的增压空气泄放控制系统,并在B6135-ZG20涡轮增压柴油机上实现了最大爆发压力的闭环控制。这一研究进一步改善了增压系统的性能,也为模糊控制开辟了一个新的应用领域。     

多循环脉冲爆震发动机流场数值研究

针对二维带有收敛扩张喷管的脉冲爆震发动机模型，采用带基元化学反应的Euler方程组和H2、空气的9组分20基元反应，对发动机在前六个工作循环的流场进行了数值模拟。通过对前几个循环流场进行比较，发现脉冲爆震发动机在第五个循环后流场就基本稳定，单循环得到的流场和多循环稳定后的流场有很大的差别，同时喷管对发动机内流场影响特别大。     

Theory of Disappearance of the Electric Signal Induced by an Aircraft Jet Engine in the Afterburner Regime

Electrical aspects of aircraft jet engine operation are considered. A phenomenon previously observed experimentally, namely, the disappearance of the engine current and alternating electric signal induced by the engine jet in the afterburner regime, is explained. It is shown that this phenomenon results from the detachment of electrons from negative ions when the gas temperature in the afterburner increases. This leads to an increase in the effective conductivity of the gas. As a result, the engine current circuit is closed on the internal duct walls and engine charging becomes insignificant.A physico-mathematical model of the electrical processes in the afterburner is formulated and model problems are solved.     

气缸垫对机体受力和缸套变形影响的实验研究

某四缸柴油机在试制中出现机体裂纹现象，为保证内燃机正常工作，机体裂纹问题急待处理．应用力学理论对此进行分析，得出机体裂纹是由机体受力不均匀引起的结论．同时采用实验应力分析方法，对两种四缸柴油机机体进行了对比实验研究，在实验中发现了缸垫对机体受力和缸套变形的影响，从而提出了一种有效的改进方法，使机体的应力有明显下降，并不再出现裂纹，也未出现漏油、漏气和活塞拉缸等不良现象，大大提高了产品可靠性．     

用固体润滑剂改善汽车刮水胶条使用性能的研究

作者将含有MoS_2和石墨的不同配方的固体润滑涂料刷涂在几种国产汽车刮水胶条上,并分别于干摩擦和水润滑的两种刮刷状态下,就固体润滑剂改善刮水胶条的擦拭性能进行了试验研究,指出这是使刮水胶条降低擦拭阻力、提高刮刷效果的可行途径,同时强调配制涂料时应当选用颗粒细小而均匀的固体润滑剂粉末。     

内燃机活塞环－缸套摩擦功耗的设计计算方法之研究

以往在计算内燃机活塞环－缸套摩擦副的摩擦功耗时，只是计算活塞环与缸套之间流体润滑剂的粘性剪应力，这显然不能客观地反映出该摩擦副的润滑状态。实际上，活塞环－缸套间的摩擦力产生于两个方面，一是粘性流体的剪应力，二是摩擦界面相互接触峰元的剪切作用。然而截至目前，针对这两方面进行全面分析研究的报道却还很少，因此，为了给低摩擦功耗环组的设计提供科学依据，基于对活塞环在运动过程中润滑状态的分析，提出了一种适用于不同类型内燃机设计计算的活塞环－缸套摩擦功耗的计算方法，并以其对现有结构的Ｓ１９５柴油机活塞环－缸套摩擦副的摩擦功耗进行了计算，同时还对影响摩擦功耗的因素作了考察与讨论，利用台架试验测量油膜厚度的方法对这种算法进行试验验证的研究结果表明，理论值与实测值吻合得很好。     

Detonability of simple and representative components of pyrolysis products of kerosene: pulsed detonation engine application

The use of liquid fuels such as kerosene is of interest for the Pulse Detonation Engine (PDE). In this context, a representative gaseous mixture of the lighter products resulting from the decomposition of a kerosene of type JP-10 was studied. The detonability limits of simple components (hydrogen, ethylene, propylene) and mixtures of these components were tested in a 50 mm diameter and 2.5 m long detonation tube. This dimension is compatible with the applications of the aircraft industry and more particularly the PDE. The influences of the nitrogen dilution, geometry of the DDT device (Schelkin spiral), ignition energy and initial pressure were investigated. This paper was based on work that was presented at the 19th International Colloquium on the Dynamics of Explosions and Reactive Systems, Hakone, Japan, July 27 - August 1, 2003. Communicated by J.E. Shepherd