This paper studies drag reduction on a reference bluff body (Ahmed body) with single dielectric barrier discharge (SDBD) actuators, also called plasma actuators, located at different positions on the model’s rear part with a spanwise arrangement. This active actuator modifies the laminar-to-turbulent transition leading to reattachments of separated flows on the body. A reduction of actuator efficiency when increasing velocity is the main limitation of this method. The main aim of this work is to find a solution for this problem by employing passive flow control to improve the SDBD actuators’ efficiency. For this purpose, rear linking tunnels are added to the model as a novel passive flow control. Numerical simulations were performed to determine the best position of the active actuators on the model. The next step is to study the effect of the passive and active flow control on drag reduction and investigating the combination of these methods for improving the active flow control performance at four different freestream velocities (Re ​= ​0.289 ​× ​10⁶–0.722 ​× ​10⁶). The positive effect of this combination is noticeable (a 59% increase in the SDBD actuator’s efficiency for Re ​= ​0.722 ​× ​10⁶), and the non-linear behaviour of this combination leads to high drag reduction of between 13.29% and 17.96% for different Reynolds numbers.

本文研究了具有单电介质势垒放电（SDBD）执行器（也称为等离子执行器）的基准钝体（艾哈迈德氏体）上的减阻，该执行器位于模型后部的不同位置，并呈展向分布。该主动致动器修改了层流到湍流的过渡，导致分离的流重新附着在主体上。当增加速度时致动器效率的降低是该方法的主要限制。这项工作的主要目的是通过采用被动流量控制来提高SDBD执行器的效率来找到解决该问题的方法。为此，将后部连接隧道作为一种新型的被动流量控制添加到模型中。进行了数值模拟，以确定主动致动器在模型上的最佳位置。⁶ –0.722×10 ⁶）。这种组合的积极作用是显而易见的（SDBD执行器的Re效率= 0.722×10 ⁶上升了59％），并且这种组合的非线性行为导致了13.29％的高减阻。不同雷诺数的17.96％。