Study On Rheological And Atomization Characteristics Of ADN/Water-Based Gel Propellant

With the gradual deterioration of environmental issues,the development of environmental propellants has always been the industry goal.Among them,ammonium dinitroamidate propellant(ADN)as a green,non-polluting high specific impulse propellant,has attracted worldwide attention.At the same time gel propellants compared with the liquid,it can be long-term storage,not easy to leak and not shaking in the tank,the performance of the collision is not sensitive.Compared with the solid propellant,but also to achieve adjustable thrust,multiple starts,and relatively high specific impulse,storage,transportation and maintenance are very convenient,with a wide range of applications.At present,there are few studies on the gel state of ADN,and there is not a comprehensive data support and characterization.At the same time,the numerical calculation model of the gel fluid,the atomization effect and so on are all hot spots for research.In order to broaden the application field of ADN and to fill the gap in this area,this paper uses the method of numerical simulation and experiment to study the rheological and atomization characteristics of ADN/water-based gel propellant,including the following contents:First of all,based on the purpose of this study,ADN/water-based gel propellant test system was established.Select the appropriate gel,ADN/water-based gel preparation,prepared at different concentrations of gel propellant.The viscosity of the gel was measured by a rotational viscometer and the rheological index and the viscosity coefficient were obtained by mathematical solution.After that,according to the requirements of atomization experiment,we design and process the structures such as intercommunication,swirling nozzle and liquid storage tank,build the pipeline system and finally establish the whole atomization test system.Considering the research progress,according to the purpose of this study,the design of cyclone atomization and atomization atomization experimental scheme.Secondly,according to the rheological thermodynamics of gel propellant,the related mathematical model is established,and the constitutive equation,the governing equations and the viscosity equation are determined.The physical model of different pipeline structures was established.Based on different physical models,the grid drawing and the example verification were completed.Based on the above,the rheological properties of ADN/water-based gel propellants were studied.The effects of pipe diameter,bending radius ratio and shrinkage radius ratio were investigated to investigate the rheological properties.Secondly,for the swirl nozzle structure,experimental study on swirling atomization of ADN/water-based gel propellant was carried out.Malvern particle size analyzer and high-speed photography system were used to record the atomized images under different pressures.The obtained images were analyzed and the influence of injection pressure on the spray patterns was summarized.At the end of this paper,we studied the influence of different atomization parameters on the atomization characteristics of ADN/water-based gel propellants under intercalating nozzles,and analyzed the coupling law between different parameters.The effects of spray system parameters such as injection pressure,impact angle and orifice diameter on the atomization characteristics of spray,spray cone angle and liquid film length were studied.