Research On Optimal Design For The Electromagnetic Driven System Of Bladder Power Pump

Neurogenic bladder is a general name of bladder or urethra dysfunction disease,which is caused by pathology change or damage of central nerve system which controls micturition.And there is no effective treatment for this disease.At present,the bladder fistula bypass,the electrostimulation,the urethra catheterization drainage and the drug injection are commonly used to assist micturition in clinical.But these measures are easy to trigger urinary tract infection and complications.In order to solve these problems of urinary system infection and complications which are caused by assist micturition measures,a extracorporeal electromagnetic driven assist micturition system(also called bladder power pump)was proposed in the early stage of the research group.The core institution of bladder power pump is the electromagnetic drivern system which is composed by electromagnet and magnet mover.At present,there are many problems in the electromagnetic driven system,like the weight and the volume are larger,the portability is poor.These problems cause the bladder power pump to be diffcult to meet the requirements of animal and clinical research.Therefore,the electromagnetic drivern system of bladder power pump is optimized design in this paper,the electromagnetic driven performance and the temperature rise performance of the electromagnetic drivern system,and the micturition performance of bladder power pump are simulated by finite element method.The experiment researchs are carried out by simulated experiment platforms.The concrete of works are as follows:The structure of electromagnet was preliminary designed based on the theory of electromagnet design and the composition principle of bladder power pump.The optimization design models of magnet mover and electromagnet were established based on the optimization theory and the characteristics of physiological tissue structure.The optimal structure design parameters were obtained by using the sequential quadratic programming(SQP)algorithm to solve these models.The 3D models of the electromagnetic drivern system before and after the optimization were established by using Solidworks software.The static magnetic field and the transient magnetic field were simulted by using ANSYS Workbench software.The magnetic field distribution nephograms of the electromagnetic drivern system and the variation rule of the electromagnetic driven force were obtained.The temperature field of the electromagnet was simulted by using the electromagnetic-thermal coupling analysis function of ANSYS Workbench software.The temperature field distribution nephograms of the electromagnet and the curves of the temperature rise affected by times were obtained.The 3D models of bladder power pump before and after the optimization were established by using Solidworks software.The micturition performance of bladder power pump was simulted by using the fluid-structure interaction analysis function of ANSYS Workbench software.The distribution nephograms and the variation curves of the intravesical pressure and the urine flow were obtained.According to the optimization design results,the physical models of the electromagnetic drivern system and bladder power pump were made,and the simulated experiment platforms were built.The electromagnetic driven performance,the temperature rise performance and the micturition performance were obtained by expreiment.The validity of the optimization design models and the finite element models were verified by expreiment.The research results show that:the optimization design models and the finite element models are effective and practical,comparing to before optimize,the volume of electromagnet is reduced by 65.45%,the weight of electromagnet is reduced by 60.25%,the volume of magnet mover is reduced by 14.03%,the electromagnetic driven force is increased by 2.09%,the maximum of intravesical pressure is increased by 2.74%,the maximum of urine flow rate is increased by 14.22%,the temperature rise is only increased1.64~oC.The research can provide theoretical and technical guidance for designing of bladder power pump which is portable,reliable and applicable for animal and clinical studies.