Development Of Medical Adjustable Atomizer Based On Venturi

Atomizing inhalation therapy is an important treatment method for respiratory system related diseases.For critically ill patients,compressed atomizer can generate moist air to help patients moisten the airway,which can avoid more complications caused by dry breathing.For patients with respiratory diseases,the compressed atomizer can atomize liquid drugs to form tiny drug droplets,which can be inhaled through the respiratory tract and directly reach the respiratory tract lesions.In this way,not only the utilization rate of drugs can be improved,but also the absorption of patients can be accelerated.However,the current medical compression atomizer has simple structure and uneven atomization concentration,which makes the atomization treatment effect not ideal,drug waste,and even make patients feel uncomfortable.Therefore,the development of medical adjustable compression atomizer to improve the atomization effect has important theoretical significance and practical value in the field of atomization.The main work of this paper is as follows:(1)The working principle and atomization process of the medical compression atomizer were analyzed.The actual fluid flow of the three-dimensional physical model of the medical compression atomizer was studied and analyzed.The Solidworks modeling software was used to establish the physical model of the atomizer.The KH-RT prediction model and k-εturbulence model,established the mathematical model in the process of liquid atomization;analyzed the stress distribution in the atomization process of liquids,established the atomization effect is the main performance index is composed of three aspects: the liquid after atomization droplet size proportion,under 5μm export momentum,and the atomizing rate.(2)By using the method of VOF-DPM and the finite element analysis software Fluent,the influences of gas flow rate,liquid channel width and crushing baffle shape on the atomization effect were numerically analyzed.The numerical simulation results show that the atomizer on the original structure,the increase of gas velocity,droplet diameter can improve the exit of under 5μm accounted,with the increase of gas velocity,liquid atomization droplets kinetic energy will be improved after;under the condition of other condition is constant,change the liquid channel width,with the increase of liquid channel width,sucked up liquid volume increased,droplet velocity increases,the kinetic energy of liquid atomization droplet after is increase,but the exit of droplet diameter under 5μm accounted,particle size distribution also can become relatively dispersed;shape optimization for crushing the atomizer internal baffle,other things being equal,the optimized conical baffle structure broken,not only improve after the liquid atomization droplets kinetic energy,and droplet diameter can be the exit under 5μm accounted for about 5% than ascension.(3)The control system of the adjustable medical compression atomizer is built.The control system is divided into hardware circuit design and software design;hardware circuit mainly includes motor drive circuit and current signal detection circuit,software design mainly includes lower computer software and upper computer software.The designed adjustable medical compression atomizer has four gears: the gas flow rate of first gear is 4L/min,the gas flow rate of second gear is 6L/min,the gas flow rate of third gear is 8L/min,and the gas flow rate of fourth gear is 10L/min.The atomization effect of each gear is different,so as to meet the needs of different patients for atomization effect.Using 3D printing technology to produce atomizer nozzle and debug test system software.(4)Atomizing performance analysis of the atomizer.Through the method of test measurement,the actual atomizing performance of the medical adjustable atomizer is analyzed,and the following conclusions are drawn: under the condition of the same kind of liquid,improving gas flow rate,rate of the spray atomizer from 0.348 m L/min up to 0.657 m L/min,the range of the droplet from 115 mm to 237 mm,the exit droplet diameter under 5μm proportion can be increased from 46.56% to 59.52%;in view of the different concentrations of physiological saline,under the condition of the same gas velocity,the slower the liquid concentration,the higher the atomizing rate,droplet diameter at the exit under 5μm proportion also reduces,but little impact on export the kinetic energy of the liquid concentration;in different liquid broken baffle,the same conditions of gas velocity,improve the solution after crushing baffle,the exit of droplet diameter under 5μm accounted for about 5% than ascend,atomization rate increase 0.05 m L/min,the range of the droplet from 195 mm to 214 mm.