【作者】 金江明；

【导师】 吴荣仁； 洪伟荣；

【作者基本信息】 浙江大学 ， 化工过程机械， 2010， 博士

【摘要】 对大型活塞压缩机而言,实现排气量的无级连续调节必不可少。相对于其它无级气量调节方法,部分行程顶开进气阀排气量调节方式不仅实现了排气量全量程的无级连续调节,而且使压缩机仅压缩实际需要的气体,在减少排气量的同时也降低了能耗。目前,国外贺尔碧格公司已开发出类似的产品,但因为价格和可靠性问题,使其在国内推广应用受到了限制；同时国外COOK等压缩机公司也将压缩机气量调节装置的研究作为技术开发重点,已有相关的研究计划见诸报导。因此研制开发一套符合我国国情并有自主知识产权的部分行程顶开进气阀气量无级调节系统意义重大。论文以教育部博士点基金项目“变质量压缩系统新型回流气阀运动特性研究”和“十一五”科技支撑计划项目“高效节能压缩机关键技术研究”(编号:2008BAF34B13)为依托,对气量调节工况下的压缩机热力循环过程和气阀运动规律进行了较为深入的理论和实验研究,研制开发了能够实现0—100%全量程气量无级调节方法的关键技术和装置,并成功应用于大型石化活塞式压缩机中。现场使用效果表明,本论文所开发的部分行程顶开进气阀压缩机气量调节装置运行可靠、节能效果明显。本文的主要研究内容有：1.建立了气量无级调节工况下压缩机热力循环模型,理论计算了排气量与进气阀顶开角度的变化规律,实验室压缩机试验表明计算结果同测量基本吻合；2.建立了气量无级调节工况下阀片动力学模型,分别给出了基于实际气体状态方程和理想气体状态方程的气阀阀片运动方程组,通过试验验证和理论计算对比研究,揭示了气量调节工况下气阀阀片的运动规律；3.建立了气量无级调节下气阀多自由度运动模型,通过计算正常工况和气量无级调节工况下气阀运动过程表明,用于气量调节的压叉的存在将大大地减少阀片侧倾运动；4.设计了一套应用于气量无级调节装置的控制系统,提出一种能实现压缩机与液压分配器保持转速与相位同步的反馈控制方法,构建了上位机控制压缩机运行、下位机控制气量调节的系统构架,提出了应用于气量无级调节系统的压缩机多级控制策略；5.研制了一套能应用于爆炸性气体区域的气量无级调节装置,并成功应用于镇海炼化的工业现场大型活塞压缩机上；6.借助有限元工具,分析了在气量调节工况下压叉与阀片的碰撞过程,评估了气阀装配、压叉重量和不同材料的压叉对阀片碰撞过程中最大应力的影响。更多还原

【Abstract】 Reciprocating compressors are widely used in industry. It’s really important to realize stepless capacity regulation for reciprocating compressor. The stepless capacity regulation method by depressing the suction valve makes the inhalational intake gas back to suction chamber during partial compression stroke, only the required gas is compressed. By this method, compressor capacity can be regulated steplessly in a range between 0-100%and the power consumption is saved proportionally with capacity. By now, the similar capacity regulation system of reciprocating cpmpressor developed by Hoerbiger has been widely used in the world, but it is difficult to be popularized in domestic industry for the high price and reliability limitation. It is still the major research interest for the other international compressor valve companies (eg. COOK) to study the stepless capacity regulation facility since relevant projects have been reported. Therefore, it is great need to develop the stepless capacity regulation system, which conforms national conditions of our country and has independent intellectual property rights.Based on the National Key Technology R&D Program "Key Technology Development Program for High Efficiency Compressor" (No.2008BAF34B13), and Doctoral Fund Project from Education Department "Research on Valve Dynamic in case of Reflow situation for Variable Mass Compressor System", the thermal cycle and valve dynamic in the case of stepless capacity regulation are deeply studied by theroy and experiment in this dissertation, the key techonolgy and equipment for the 10～100% capacity regulation system are also developed. The field tests show that this stepless capacity regulation equipement possesses smooth operation and significant energy savings.The main researche topics in this dissertation are as follows:1. A theoretical thermal cycle model in case of stepless capacity regulation has been developed. Capacity variation with the unloader crankangle has been calculated. The calculation result is in accordance with experiments.2. The valve dynamic model in case of stepless capacity regulation has been established. The valve dynamic differentical equations based on real gas state equation and ideal gas state equation respectively in stepless capacity regulation are derived in this dessisation. Valve plate dynamic motion in stepless capacity regulation has been revealed through computer calculation and experiment.3. Multiple freedrom motion model for compressor valve in the case of stepless capacity regulation has been developed. The valve plate motions under normal operating condition and stepless capacity regulation condition are calculated respectivly and compared. The calculation results show that the unloader in stepless capacity regulation makes valve plate incline impact velocity reduced obviously.4. A control system used in stepless capacity regulation system has been designed. A method to keep the rotating speed and phase synchronization between the compressor motor and hydraulic distributor has been proposed. System framework, which uses the upper computer to control the operation of reciprocating compressor and uses the lower computer to control the stepless capacity regulation system, is constructed. The multiple stage control strategy of reciprocating compressor in stepless capacity regulation has also been proposed in this dissertation.5. The stepless capacity regulation system, which is suitable for explosive gas zone has been developed, which has been successfully applied on large-scale industry reciprocating compressor in Zhenhai Refining & Chemical Company(ZRCC).6. By using the finite element analysis tool, the impact process between the unloader and valve plate has been demonstrated in the case of stepless capacity regulation situation. The influence factors for the maximum stress in the valve, which are generated by valve assemble errors, unloader material or unloader mass and so on have been evaluated.更多还原