Abstract: The process of mass transfer in nano-fluids was simulated by using lattice Boltzmann method based on two different ways，one is based on the finite volume of a particle method and the other is based on the point source of particles method.In those methods，the modified Boltzmann equation and the equation of mass diffusion coefficient in nano-fluids was given，moreover，the numerical results were compared with Xuan Yimin’s experimental data.Finally，the mass diffusion coefficient of CO2 in nano-fluids were calculated，the results show that the micro-perturbation of nano-particles greatly enhanced on the mass transfer，provide a new way for CO2 absorption，and proved that the reason of enhancement of mass transfer in nano-fluid is mainly relied on the convective mass transfer that was caused by the micro-perturbation of nano-particles.

Key words: nano-fluids, diffusion coefficient, enhanced mass transfer

摘要： 使用Boltzmann方法对纳米流体中的传质过程进行了模拟，给出了修改后的Boltzmann方程和计算纳米流体中扩散系数的方程，通过两种方法，基于有限体积颗粒的LBE方法和基于点源颗粒的LBE方法进行了模拟，并与宣益民的实验进行了对比。最后计算了CO2在纳米流体中的扩散系数，计算结果表明，纳米流体因为其纳米颗粒的微扰动对传质有着很大的强化效果，为CO2吸收提供了一种新思路，并且证明了纳米流体的强化传质主要是靠对流传质。

关键词: 纳米流体, 扩散系数, 强化传质