A non-lumped dynamic simulation method of sorption compressor for sorption cryocooler

A dynamic analysis of sorption compressor is motivated by the design of a practical sorption compressor. In this paper a non-lumped dynamic simulation method based on a non-isothermal parameter has been developed. An algorithm for simulating the dynamic behaviors of sorption compressor involving mass and energy transport is described and is calculated using Computational Fluid Dynamics (CFD). The calculated time-dependent pressure and temperature across the sorption compressor are obtained and verified by experiments. Then, the effects of thermal gradient and non-equilibrium adsorption–desorption on the net gas outflow from the sorption compressor are also investigated. It is shown that thermal gradient and non-equilibrium adsorption–desorption can significantly affect the net gas outflow with the same total heat input.     

Effects of airfoil-probe tubes on the flow field of a compressor cascade

To explore the effects of airfoil-probe tubes and its installment position on the flow field of the compressor cascade,and find out the mechanism that how the airfoil-probes affect the aerodynamic characteristics of the compressor cascade,this paper performed both numerical and experimental works on the same compressor cascade.The experiment mainly focused on the cases of low Mach number (Ma =0.1),and cases with different Mach numbers (0.1,0.3,0.7) and different incidence angles (-5,0,5) are investigated by the numerical method.The case without the airfoil-probe tube was referenced as the baseline,and other three cases with the airfoil-probe tubes installed in different chordwis positions (30％,50％,70％ of the chord length) were studied.The diameter of the airfoil-probe tube is 3ram,which is configured as 300％ amplification of some particular airfoil-probe according to the geometrical similarity principle.The results show that the airfoil-probe tubes have a negative influence on the flow capacity of the cascade at all investigation points.The separations and the large scale streamwise vortices that induced by the airfoil-probe tube on the pressure side cause most the losses at the high Mach number.The influence of the airfoil-probe tube on the flow field in the vicinity of the pressure side surface is local separation at the low Mach number.The airfoil-probe tubes also have a clearly effect on the leakage flow.It decreases the mass flow of the leakage flow and weakens the intensity of the leakage vortex,but enlarges the influence area.The total pressure loss of the case that the tube is installed at the half chordwise position is generally lower than other cases especially at the high Mach number,it can even decrease the losses compared with the basic case.     

气动潜孔锤跟管钻进技术在岩土工程勘察施工中的应用

以渤船重工新型总装生产线工程岩土工程勘察项目为依托，应用KG940 A型高风压履带式潜孔钻车﹑采用气动潜孔锤跟管钻进工艺，结合空气正循环排渣方式，摸索总结出一套针对复杂破碎覆盖层的干式成孔新方法，钻进效率及钻孔质量显著提高，为岩土工程勘察勘探孔施工增添了一种新的思路。     

Acoustic power measurement of linear compressors

The linear compressor works as an important driver for high frequency regenerative cryocoolers. The acoustic power output of the compressor is a critical parameter in the design and the optimization of a linear compressor. To measure this parameter, several approaches based on different theories have been developed. In this paper, the RC load approach and the back chamber approach have been applied to a linear compressor to measure the acoustic power output. The results measured by the approaches indicate a good consistency with the theoretical calculation and reveal the connections between different approaches.The difference between the acoustic power at the piston surface and the exit of a linear compressor has been analyzed based on the experimental results from the RC load approach and the back chamber approach. The volume flow rate difference which accounts for the acoustic power difference is studied theoretically. Furthermore, based on the RC load approach, the optimum impedance together with the impedance cloudy map for the linear compressor to reach its highest efficiency has been obtained by analyzing the experimental and the theoretical results.     

CO压缩机优化运行总结

为确保原CO压缩机在净化系统升级改造项目实施后能安全稳定运行,采取了流程优化、工艺条件论证、设备缺陷排查、联锁指标重新确定等一系列措施。改造措施实施后,CO压缩机出口压力稳定在3.23 MPa左右,有效缓解了前后工序压力波动对压缩机稳定运行的影响,各级水冷却器的换热效果也得到了较大的改善。     

螺杆式空气压缩机智能控制技术研究与应用

根据国家关于空气压缩机节能降耗及智能化控制要求,针对空气压缩机耗能运行现状、控制方式落后等问题,采用PID控制器、PLC智能控制、工业以太网等技术,设计了空气压缩机组智能控制系统。实现空压机组节能降耗、智能控制、远程监控、无人值守等功能,对于企业设备自动化化管理及经济安全运行具有重要意义。     

基于混合润滑模型的往复密封动特性研究

为研究往复运动密封性能,采用MatLab数值方法建立一种混合润滑模型,该模型包含弹性力学、流体力学和接触力学分析。基于混合润滑模型,研究粗糙度和往复速度对动态往复密封摩擦力、泄漏量和油膜厚度等密封性能的影响规律,揭示液压往复密封机制。结果表明:往复运动密封圈处于混合润滑状态,接触区不仅有流体压力,还包含粗糙度接触压力;存在临界粗糙度σ_c和临界速度u_c,当粗糙度σσ_c时,随粗糙度的增大内行程的泄漏表现为越来越小的内泄漏,当σ≥σ_c时,随粗糙度的增大内行程的泄漏表现为越来越大的外泄漏;当速度uu_c时,净泄漏量随速度的增大表现为越来越小的外泄漏,当u≥u_c时,净泄漏量随速度的增大表现为越来越大的内泄漏;随着粗糙度的增加,膜厚与内行程的摩擦力增大,而外行程的摩擦力无明显变化;随着速度的增加,油膜厚度增加,内行程摩擦力减小,而外行程摩擦力变化很小。     

40000m~3/h空分设备变负荷操作及过程优化

主要探讨了冶金用制氧机组如何适应炼钢炼铁需求量的不断变化,减少氧气放散。通过对40000 m3/h制氧机组进行变负荷操作以及对操作过程的优化,实现了节能降耗、减少氧气放散的目的。     

污水处理场4M10-34/78-76型往复式空气压缩机改造

无油润滑是现代成熟的压缩机润滑技术,它节省了能源,简化了工艺流程,提高生产效率,本次4M10-34/78-76型往复式空气压缩机少油润滑改为无油润滑着力于降低设备故障频率,延长设备使用时间,降低检修所产生的费用,降低生产停工产生的损失。