进气参数对柴油机排放及性能的影响

结合CY6102BZLQ柴油机开发研制过程,针对中冷器参数、增压器和进气涡流的选择及这些因素对柴油机排放和性能的影响,确定该柴油机的参数及方案,为今后其他机型的开发提供参考。     

基于模糊控制的大客车冷却系统

冷却系统是发动机的重要组成部分,分析了传统冷却系统的不足,设计了基于模糊控制发动机电子控制冷却系统,该冷却系统能够实现散热风扇的无级变速,使发动机工作在最佳温度,使之更经济、更环保,给出了模糊控制器的仿真结果以．及模拟情况下工作稳定可靠。     

CD法开挖隧道的顶板破坏机理分析

在隧道修建过程中，CD法被广泛用于软弱围岩隧道和大断面隧道的修建。工程经验表明，CD法比全断面法更能够减少对隧道的扰动，降低顶部围岩塌陷的可能性，但目前对该经验的认识仍缺乏足够深入的了解。比如，CD法隧道顶部的塌陷机理，相比全断面法的定量优势比较等。为此，提出了一种预测CD法开挖隧道顶板破坏机理的运动学方法。推导了确定塌块形状的理论解。所提出的方法与全开挖方法进行了比较，证明了方法的合理性和CD法开挖的优越性。研究发现，与全断面开挖的结果相比，CD法开挖可以显著降低顶板坍塌的高度，提高顶板稳定性的安全系数。     

Constructal design of tree-shaped microchannel disc heat sink with wavy walls北大核心CSCD

［Objective］To meet the efficient thermal management needs of electronic devices such as ships and underwater vehicles, this study focuses on the constructal design of a tree-shaped microchannel disc heat sink with wavy walls. ［Method］A design prototype of the heat sink with wavy walls is first proposed. Based on constructal theory, the amplitude and wavelength of the wavy walls are designed under the constraints of fixed heat sink volume and fixed microchannel volume by maximizing the comprehensive performance evaluation criteria (PEC) while considering both heat transfer and flow pressure drop. ［Results］The results show that the wavy walls increase the heat transfer surface areas and generate vortices in their cavities, effectively reducing the maximum temperature. When the inlet Reynolds number is fixed at 700, 900 or 1100 respectively, the maximum temperature is reduced by 13.5 K by increasing the amplitude of the wavy walls, while the pressure drop increases significantly; and the maximum temperature is reduced by 4.7 K by reducing the wavelength of the wavy walls, while the pressure drop increases slightly. There are optimal amplitudes that raise the comprehensive performance evaluation criteria to extreme values for given larger wavelengths, while the comprehensive performance evaluation criteria increase monotonously as the amplitude increases for given smaller wavelengths. ［Conclusion］Wavy walls can significantly improve the thermal performance of tree-shaped microchannel disc heat sinks, and the use of constructal design can realize optimal geometric constructs with optimal comprehensive performance evaluation criteria. © 2023 Authors. All rights reserved.     

海洋油气平台油气分离中控系统仿真开发

从海洋油气平台油气分离中控系统的控制逻辑出发，简化抽取油气分离系统主要部件的控制模型，采用分段线性函数近似处理原本复杂的流量函数和容积函数，降低模拟仿真难度。在Unity3D中实现海洋油气平台油气分离中控系统作业仿真，可为海洋油气平台研发提供必要支持。     

集控室兼作防海盗安全舱室设计分析

以某新制大型挖泥船项目为例,实施将集控室改进后兼作防海盗安全舱室的设计优化方案.从舱室结构强度、电源系统、安全门、通信系统、视频监控系统、应急爬梯、通风、生活设施等设计方面详细介绍该优化方案.通过与独立防海盗舱室设计方案的比较,优化方案具有节省空间、完善功能、降低成本等多方面优势.经船舶检验机构和船舶所有人认可,优化方...