含阻系统中多孔板的流动分析及其工业应用研究

发布时间：2018-03-29 16:25

本文选题：含阻系统　切入点：多级孔板　出处：《浙江大学》2016年博士论文

【摘要】：多孔板是管路系统中进行压力和流动调节、水力空化和吸声降噪的重要元件,对满足系统特定操作条件、保护设备与系统的安全稳定具有重要意义。随着国家重大工程的建设与发展,传统管路系统已不能满足复杂工况下的安全稳定运行要求；利用多孔板作为管路系统的外加组成元件,可起到对管路系统的压力与流量控制、水力空化和吸声降噪等作用。尤其在国际社会对节能环保越来越关注、国家政策对于先进制造越来越重视的背景下,开展对孔板、阀门和换热器等流动分析具有重要的科学意义与工程价值。本文在浙江省重大科技专项“极端工况下高效节能减温减压技术及装置的研制与应用”(2012C11018-1)、“抗污染超滤技术在海水淡化预处理中的研究与应用”(2012C13009)和“流程工业高效节能技术与绿色装备”浙江省重点创新团队项目(2011R50005)的支持下,通过数值模拟与实验方法,对多孔板的流动及其典型工业应用进行了研究分析。主要研究内容和成果有：首先,建立了多孔板在管路中的含阻系统模型。从系统分析方法入手,对弹簧滑块系统、直流电路系统、流场压降系统和平板传热热阻系统进行了分析研究,并对计算流体力学、场协同分析和实验分析三种流动分析方法进行了阐述；提出了含阻系统的概念,即其是一种系统分析方法,由阻元、过体和势头三个部分组成,可直接建立阻元对于势头的影响关系；结果表明采用其开展基于孔板结构的性能预测具有一定准确性。其次,建立了单级孔板的数值模型,开展了单相流和两相流分析,将典型模型与现有的文献结果进行对比验证,分析了孔板的孔板厚度、开孔率、中心孔和孔间距对于阻力特性和空化特性的影响；结果表明：开孔率对孔板的压降水平表现敏感,中心孔的存在可使压降水平下降约10%；出口压力较小时更容易发生空化；含阻系统的分析方法可较好分析开孔率等不同参数下的孔板压降水平等。再之,建立了多级孔板的数值模型,开展了阻力和气动特性分析,研究了两级孔板板间距、相同总空间下的多级孔板、两级孔板中心孔偏心和两级孔板旋转错位等对阻力特性和气动特性的影响；结果表明：当板间距增大到一定程度后压降不再上升；在相同空间下的多孔板结构板间距与压降水平在同一速度下成线性关系；偏心度较大时最大马赫数较高；旋转错位角较小时流动的影响范围较广；含阻系统的分析方法可对偏心距和旋转错位问题的压降特性等进行分析。最后,针对先导式截止阀、化工生产后处理过程集成装备蜂窝夹套、含多级孔板的减温减压装置等三种含孔板结构的典型工业装备进行了研究。(1)对先导式截止阀的阀芯处的流动特征进行了数值分析,并用实验结果进行了验证；对不同孔结构下的流动和汽蚀特性进行了研究,提出了基于含阻系统分析方法的先导式截止阀阀芯孔结构的设计方法。(2)对化工生产后处理过程集成装备中蜂窝夹套换热器进行了数值分析,并用实验结果进行了验证；对不同的孔分布情况下的传热与压降特性进行了分析,提出了基于含阻系统的蜂窝夹套换热器的孔分布设计方法。(3)对减温减压装置中多孔板的应用进行了研究,对多级孔板的马赫数和多级减压情况进行了数值分析,提出了应用含阻系统思维的减压阀内多级减压孔板的设计方法。结果表明：在含孔板结构的三种典型工业装备中,含阻系统的分析方法可较好地指导结构优化设计。此外,本文还提出了带手轮的两级孔板调压装置、螺旋错位型两级稳压孔板装置、可用于管路多级压力调节的孔板法兰、带波纹通道孔板的微通道板式换热器等新型多孔板或含多孔板的结构装置,作为含孔板结构装置的创新设计探索。
[Abstract]:The porous plate is the pressure and flow regulation of the pipeline system, the important components of hydraulic cavitation and noise, to meet the specific operating conditions, has important significance to protect safety and stability of equipment and systems. With the construction and development of major national projects, the traditional pipeline system can not meet the requirements of the safe and stable operation of the complex condition; the use of porous plate as external piping system components, can play the pressure and flow control of the pipeline system, hydraulic cavitation and noise effect. Especially in the international community more and more attention to energy saving and environmental protection, the national policy more and more attention to the advanced manufacturing background, carried out on the valve plate, and a heat exchanger flow analysis has important scientific significance and engineering value. In this paper, in Zhejiang Province, a major science and technology projects, energy efficient under extreme conditions of temperature and pressure reduction technique and device The development and application "(2012C11018-1), anti pollution of ultrafiltration technology in research and application in the pretreatment of seawater desalination (2012C13009)" and "process industry high efficient energy saving technology and green equipment" Zhejiang province key innovation team project (2011R50005) support, simulation and experimental methods of value through the analysis of the number. The porous plate flow and its application in the typical industry. The main research contents and results are as follows: firstly, water resistance system model of porous plate in the pipeline. Based on the system analysis method of spring slider system, DC system, flow pressure drop and heat transfer resistance plate system system is analyzed, and the calculation of fluid mechanics and expounds the field synergy analysis and experimental analysis of three kinds of flow analysis method; put forward the concept of system which contains the resistance, is a system analysis method, the resistance element, a body and a momentum of three Parts can be directly set for momentum impact resistance element; the results show that the use of the performance of orifice structure based prediction has certain accuracy. Secondly, a numerical model of single stage orifice, the single-phase flow and two-phase flow analysis, the typical model and the existing literature results were verified. Orifice plate thickness analysis, porosity, impact resistance and Kong Hekong center spacing for the cavitation characteristics; the results show that the opening rate of pressure drop in horizontal hole plate sensitive, center hole can make the pressure drop levels decreased by about 10% hours; the pressure of the outlet is more prone to cavitation; analysis method drag system can be used to effectively investigate the opening rate of different parameters of the orifice pressure drop level. Then, set up a numerical model of multistage orifice, the resistance and aerodynamic characteristics analysis, studied two orifices Multistage orifice plate spacing, the same total space under the influence of grade two hole plate central hole and two hole plate rotating eccentric displacement on the dynamic characteristics and resistance characteristics; the results show that when the plate spacing increases to a certain extent drop no longer rise; in the same space structure in porous plate spacing and voltage level a linear relationship at the same speed; larger eccentricity when the maximum Maher number is higher; the influence range of rotation angle is smaller than the dislocation flow; analysis system of resistance with eccentricity and rotation malposition of the pressure drop characteristics were analyzed. Then, according to the pilot type valve, chemical production postprocessing the process of integration of equipment honeycomb jacket, with multistage orifice temperature reducing device and other three kinds of plates with holes structure of the typical industrial equipment were studied. (1) the flow characteristics of the spool pilot valve is numerically Analyzed and verified with the experimental results; flow and cavitation characteristics of different pore structure were studied. The proposed pilot analysis method with vibration system based on valve spool hole structure design method. (2) of chemical production equipment in the postprocessing process integrated honeycomb jacket heat exchanger was carried out numerical analysis, and verified with the experimental results; on the heat transfer and pressure drop characteristics of different pore distribution are analyzed, puts forward the design method of distribution system containing resistance honeycomb jacket heat exchanger based on hole. (3) the application of temperature reducing device in porous plate is studied, the Maher number and the multi-stage vacuum multistage orifice was studied by numerical analysis, puts forward the design method of the valve with resistance of system thinking in multistage decompression orifice. The results showed that: in the three typical industrial equipment with hole plate structure, containing The analysis method of resistance system can better guide the structure optimization design. In addition, this paper also put forward the pressure regulating device two orifices with handwheel and screw dislocation type two stage stabilized orifice device which can be used for multi-stage pressure regulating orifice flange pipe, new porous plate micro channel heat exchanger with corrugated plate channel of or containing porous plate structure, as the innovative design of plate with holes structure exploration.

【学位授予单位】：浙江大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：TQ021.1

【相似文献】