In micro/nano-devices, the low-speed transport of mass, momentum, and energy through long-ducts is frequently encountered, thereby necessitating scientific investigations. Here, long-ducts of various annular cross sections conducting low-speed gas flows under the influence of a small pressure gradient are considered, in order to understand how the mass flow rate is affected by rarefaction, variations in the radius ratio, and eccentricity of annular geometries. The Boltzmann model equation is treated by a low-variance formulation and simulated by a stochastic kinetic particle-based approach, which addresses the deviation of the molecular distribution function from equilibrium to reduce computational cost significantly. An efficient parallel solver has also been developed and utilized in this research, which is validated against the reported results in the literature. The efficient kinetic particle treatment provides a powerful simulation tool to reveal multi-scale flow physics, which is essential to develop and optimize micro/nano-fluidic devices.

中文翻译：

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低速稀薄气流通过环形截面长微通道的减方差动力学模拟

在微/纳米器件中，经常遇到质量、动量和能量通过长管道的低速传输，因此需要进行科学研究。在这里，考虑在小压力梯度的影响下传导低速气流的各种环形截面的长管道，以了解质量流量如何受稀薄、半径比变化和偏心率影响。环形几何。玻尔兹曼模型方程通过低方差公式处理，并通过基于随机动力学粒子的方法进行模拟，该方法解决了分子分布函数与平衡的偏差问题，从而显着降低了计算成本。本研究还开发并使用了一种高效的并行求解器，这是根据文献中报告的结果进行验证的。高效的动力学粒子处理提供了一个强大的模拟工具来揭示多尺度流动物理，这对于开发和优化微/纳米流体设备至关重要。