Abstract: Agitators are mainly used for the preparation of the drilling and workover fluids and chemicals on offshore oil platforms. In recent years, the methods to improve the mixing efficiency are mainly limited to the optimization of the blade shape and transmission efficiency, but with few reports about the improvement in the driving mode and the mixing principle. In view of the above problems, a mixing agitator is proposed that uses pressure gas as the power to drive the agitator for two kinds of agitation: mechanical agitation and gas agitation. The mixing flow field is numerically simulated by the computational fluid dynamics (CFD) and tested by the Laser Doppler Velocimeter (LDV). The results are compared and analyzed with those of the conventional agitator. It shows that the velocity distribution above the blades of the new agitator is relatively uniform, and there are fewer low-speed areas under the agitation of bubbles, forming a stable turbulent flow. In the region below the blades, better agitation is found on the two ribs with a wider range of action for the new agitator. The new gas-driven agitator has good research and application value.

Key words: offshore platform, new agitator, gas driven, numerical simulation, laser Doppler velocimeter (LDV)

摘要： 搅拌器在海洋石油平台上主要用于钻修井液和化学药剂的配制。近年来为了提高搅拌效率,改进方法主要局限于对桨叶形式以及传动效率的优化,但对于驱动形式和搅拌原理方面的改进却鲜有报道。文章针对以上问题,提出了一种以压力气体作为动力的混合搅拌装置,即以机械搅拌和气体搅拌2种形式驱动搅拌器。以计算流体力学（CFD）对搅拌流场进行数值模拟,并通过激光多普勒测速法（LDV）对流场进行测试,并与常规搅拌器进行对比和分析。研究结果表明：新型搅拌器桨叶以上部分速度分布比较均匀。在气泡的搅拌作用下,低速区较少,形成稳定的湍流;而桨叶以下区域,新型搅拌器对2个肋部的搅拌更好,作用范围更广。因此,新型气体驱动搅拌器具有较好的研究和使用价值。

关键词: 海洋平台, 新型搅拌器, 气体驱动, 数值模拟, 激光多普勒测速法