共轴聚焦型微流控装置剪切高粘溶液连续制备双基球形发射药

Continuous Preparation of Double⁃based Spherical Propellants by Shearing High Viscosity Solution with A Co⁃axial Flowing Microfluidic Installation

为了探索连续化生产粒径可控的百微米范围内双基球形发射药工艺条件,以质量分数为10%的双基发射药溶液为分散相,采用共轴聚焦型微流控装置制备了400~700μm范围内粒径可控的双基球形发射药,并研究了两相流量比(Q_(c)/Q_(d))、芯片尺寸对其粒径和形貌的影响。通过扫描电镜、光学显微镜、密闭爆发器等测试方法,表征了样品形貌、粒径分布和定容燃烧性能。结果表明:随两相流量比(Q_(c)/Q_(d))减小,相同芯片下制备样品的中位粒径(D_(50))先增大后减小;随芯片的连续相或分散相通道内径增大,相同两相流量比下制备样品的D50依次增大。当分散相通道内径为0.85 mm,连续相通道内径为2.00 mm,两相流量比为200.00时,制备的样品单分散性好、表面光滑、内部密实、球形形状规则(平均球形度φ_(K)=0.949)且粒径分布窄(跨度span=0.09),其D50为539.94μm,平均颗粒密度ρ为1.601 g·cm^(-3)。密闭爆发器实验中,压力⁃时间曲线表明球形样品在2种装填密度(Δ_(1)=0.12 g·cm^(-3)、Δ_(2)=0.20 g·cm^(-3))下能稳定燃烧,动态活度⁃相对压力曲线符合密实球形药减面燃烧规律。

In order to explore the processing parameters for the continuous production of double⁃based spherical propellants with particle sizes in the range of hundred microns,a Co⁃axial flowing microfluidic installation was used to process the dispersed phase of a 10%double⁃based propellant solution and prepare the double⁃based spherical propellants with a controllable particle size in the range of 400⁃700μm.The effects of two⁃phase flow ratio(Q_(c)/Q_(d))and chip size on the morphology and particle size of double⁃based spherical propellants were investigated.Moreover,the morphology,particle size distribution,and constant vol⁃ume combustion performance of samples were characterized using scanning electron microscopy,optical microscope,and closed bomb test,respectively.Results show that,the median particle size(D_(50))of the samples prepared into the same type of chip increases first and then decreases with the decrease of two⁃phase flow ratio.As the internal diameter of the continuous phase or the dispersed phase channel increases,the D50 of the samples obtained at the same two⁃phase flow ratio increases suc⁃cessively.When the internal diameter of the continuous phase and the dispersed phase channels are 2 and 0.85 mm,and the two⁃phase flow ratio is 200.00,the resultant sample displays high monodispersity,smooth surfaces,dense inside,regular spheri⁃cal shapes(average sphericityφ_(K)=0.949)and narrow size distribution(span=0.09).Its D_(50)is 539.94μm,and the average parti⁃cle density is 1.601 g·cm^(-3).In the closed bomb test,the pressure⁃time curve shows that the samples with two varied packing densities(Δ_(1)=0.12 g·cm^(-3),Δ_(2)=0.20 g·cm^(-3))can burn stably,and the dynamic vivacity⁃relative pressure curve follows the regres⁃sive burning law of the dense spherical propellants.