膀胱动力泵尿道阀的设计及可靠性研究

发布时间：2018-04-04 09:15

本文选题：膀胱动力泵　切入点：尿道阀　出处：《广东工业大学》2012年硕士论文

【摘要】：神经源性膀胱是指由于人体控制排尿的中枢神经受到损害而引起的膀胱排尿功能障碍。该病可引发膀胱结石、泌尿系统感染、肾功能衰竭等并发症,给病人带来极大的痛苦,对其治疗或辅助病人排尿是医学界公认的难题。目前,对神经源性膀胱治疗尚无有效办法。针对此问题,本课题提出了一种体外电磁驱动的膀胱动力泵。通过体外电磁铁产生的电磁场对体内磁动子产生电磁驱动力,调节尿道口和输尿管口开闭,压迫膀胱排尿。模拟实验证明该泵工作原理可行,但开启尿道口所需的电磁驱动力较大,导致电磁铁结构较大。为了优化膀胱动力泵的结构,有必要对其尿液配流机构做出改进。为此,本文设计了一种新型的膀胱动力泵尿道阀。运用电磁学理论和流体力学理论,建立了尿道阀的数学模型,利用该模型仿真分析了电流和气隙等不同因素对尿道阀特性的影响。通过仿真和实验对比,验证了所建立模型的有效性。在模拟实验台上,研究了尿道阀对膀胱动力泵排尿动力特性的影响规律。结果表明：增大电磁铁电流、减小电磁铁与尿道阀之间的气隙,有利于提高最大尿流率、缩短尿流时间。尿道阀是膀胱动力泵实现尿液配流的重要部件,一旦发生失效,将导致泵失去辅助排尿作用。因此,研究提高尿道阀的可靠性具有重要的意义。为了提高尿道阀的工作可靠性,根据尿道阀的结构原理及故障树,建立了尿道阀可靠性仿真模型。基于蒙特卡罗方法基本思想,提出了尿道阀可靠性仿真算法,并仿真计算了尿道阀的可靠度、失效概率、底事件重要度和模式重要度等指标。仿真与实验结果表明：尿道阀寿命达到50000次的可靠度为0.73；弹性带脱落和老化是尿道阀的薄弱环节。研究结果可为膀胱动力泵特性分析和结构优化设计提供依据,为设计新型的辅助排尿装置提供指导,对合理设计适用于人体的生物医学装置有参考作用。
[Abstract]:Neurogenic bladder refers to the bladder urination dysfunction caused by the damage to the central nervous system of human controlled urination.The disease can lead to bladder stone, urinary system infection, renal failure and other complications, and bring great pain to patients. It is a difficult problem to treat or assist patients to urinate.At present, there is no effective method for the treatment of neurogenic bladder.In order to solve this problem, a bladder dynamic pump driven by electromagnetism in vitro is proposed.The electromagnetic field produced by electromagnet in vitro produces electromagnetic driving force on magnetomagnetic movemons in vivo, adjusts the opening and closing of ureteral and ureteral orifice, and compresses bladder urination.The simulation results show that the pump is feasible, but the electromagnetic driving force needed to open the urethra is larger, which leads to the larger electromagnet structure.In order to optimize the structure of bladder power pump, it is necessary to improve its urine flow distribution mechanism.Therefore, a new type of bladder dynamic pump urethral valve is designed in this paper.The mathematical model of urethral valve was established by using electromagnetic theory and hydrodynamic theory. The effects of different factors such as current and air gap on the characteristics of urethral valve were simulated and analyzed.The validity of the proposed model is verified by simulation and experiment.The effect of urethral valve on the urination characteristics of bladder power pump was studied on a simulated test bench.The results show that increasing the electromagnet current and reducing the air gap between the electromagnet and the urethral valve can increase the maximum urinary flow rate and shorten the urinary flow time.Urethral valve is an important part of bladder power pump to realize urine flow distribution. Once failure occurs, the pump will lose its auxiliary urination function.Therefore, it is of great significance to study and improve the reliability of urethral valves.In order to improve the reliability of urethral valve, the simulation model of urethral valve reliability was established according to the structure principle and fault tree of urethral valve.Based on the basic idea of Monte Carlo method, the reliability simulation algorithm of urethral valve is proposed, and the reliability, failure probability, bottom event importance and mode importance of urethral valve are simulated and calculated.The results of simulation and experiment show that the reliability of urethral valve is 0.73 when the life of urethral valve reaches 50000 times, and the weak link of urethral valve is the falling off and aging of elastic belt.The results can provide the basis for the characteristic analysis and structural optimization design of the bladder power pump, provide guidance for the design of a new type of auxiliary urination device, and can be used as a reference for the rational design of the biomedical device suitable for human body.
【学位授予单位】：广东工业大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：R311

【参考文献】