Development Of High-viscosity Double-barrel Rheometer And Research On Rheological Properties Of Three-base Propellant

Tri-base propellants usually refer to solid propellants with nitrocellulose,nitroglycerin(or other nitrates)and solid explosives(Nitroguanidine,RDX,etc.)as the main components.In this paper,the rheological response of three-base propellant in the mixing process was studied under different processing conditions.capillary rheometer is a method to measure the flow state and dynamic parameters of the material flowing through the pipe under the extrusion of the plunger Rod.Considering the security and rationality of the test,the substitute materials with similar properties to the three-base propellant were prepared and tested,and then the three-base propellant was tested.The three-base propellant is mainly composed of nitrocellulose,RDX and Nitroglycerin.The solvent is a mixture of acetone and ethanol.Instead,calcium carbonate and cellulose,triacetin,solvent for Ethyl Acetate.Firstly,a multi-functional high viscosity double-barrel capillary rheometer is designed and developed for the high viscosity,explosive and high sensitivity to pressure,temperature and holding time of solid propellant,the accuracy of the test results was compared and studied.Secondly,the rheological behavior of substitute material under different technological conditions was studied by using double-cylinder capillary rheometer.The rheological constitutive model was obtained by fitting the rheological characteristic curve of the substitute.Finally,the rheological behavior of the three-base propellant at different mixing and plasticizing time and the rheological response of the propellant at different testing temperatures were studied by using a multi-functional high viscosity double-cylinder capillary rheometer.The rheological constitutive model of three-base propellant was obtained by fitting the rheological characteristic curve of three-base propellant.The flow channel model of single-hole propellant extrusion molding was established by using Mesh and other software,and the simulation was carried out by using POLYFLOW software.The results show that the dual-cylinder capillary rheometer is safe and accurate,and the Williamson model can fit the rheologic characteristic curve of the three-base propellant and its substitute well The self-construction model based on the shear rate-shear stress curve has a good fitting effect.