Space propulsion of electroosmotic thrusters (EOTs) with a soft charged nanochannel is investigated considering the Navier slip boundary and constant surface charge density on the walls of slit channels. The soft nanochannel is characterized by a wall-grafted ion-penetrable charged polyelectrolyte layer (PEL). The Poisson–Boltzmann equation is solved to give the electric potential distribution based on the assumption of the Debye–Hückel linearization for the low electric potential. An analytical solution of the electroosmotic velocity through the soft channel is obtained. The thrust, specific impulse, and total input power of EOTs produced by the electroosmotic flow are presented, and then, two significant physical quantities, thruster efficiency and thrust-to-power ratio, are described. It is found that these performance curves strongly depend on the slip length, surface charge density on the walls, drag coefficient, equivalent electric double layer thickness, PEL thickness, and density ratio of the PEL to the electrolyte solution layer. By analyzing and optimizing these design parameters, the simulated EOTs can deliver the thrust from 0 μN to 10 µN as well as the specific impulse from 40 s to 100 s, and the thruster efficiency up to 87.22% is realized. If more thrust control and kinetic energy are needed for different space missions, an array composed of thousands of single EOT emitters is constructed and maintains high thruster efficiency. Moreover, during mission operation, the total potential can be simply varied to optimize the performances of thrusters at any moment.

中文翻译：

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用于空间推进的软纳米通道中的电渗推进器

考虑到纳维埃滑动边界和狭缝通道壁上恒定的表面电荷密度，研究了带有软电荷纳米通道的电渗推进器（EOT）的空间推进。软纳米通道的特征在于壁可移植的离子可穿透的带电聚电解质层（PEL）。根据Debye-Hückel线性化低电势的假设，对Poisson-Boltzmann方程进行求解以给出电势分布。获得了通过软通道的电渗速度的解析解。介绍了由电渗流产生的EOT的推力，比冲和总输入功率，然后描述了两个重要的物理量，即推力器效率和推力功率比。已经发现，这些性能曲线很大程度上取决于滑移长度，壁上的表面电荷密度，阻力系数，等效双电层厚度，PEL厚度以及PEL与电解质溶液层的密度比。通过分析和优化这些设计参数，模拟的EOT可以提供从0开始的推力μN到10μN以及40 s到100 s的比脉冲，推进器效率高达87.22％。如果不同的太空任务需要更多的推力控制和动能，则可以构建由数千个单个EOT发射器组成的阵列，并保持较高的推进器效率。此外，在任务运行期间，总潜能可以随时改变以优化推进器的性能。