The efficacy of thermal perturbations generated by nanosecond pulse driven dielectric barrier discharge (ns-DBD) plasma actuators for post-stall flow control is explored on a NACA 0012 airfoil. Baseline and controlled flow fields are studied using static pressure measurements, particle image velocimetry and constant temperature anemometry. Experiments are primarily performed at Re=0.74×10 6 (U ∞ =40 m s −1 ) and α=18°. Three regimes of forcing are identified corresponding to separation control (0.92<F + <1.52), bluff body shedding (0.23<F + <0.92) and an impulse-like response (F + <0.23). The response of the flow to a single high voltage pulse is also examined and compared to other studies of transient separation control. Results show that the global structure of the controlled flow is not specific to ns-DBD plasma actuator forcing. Rather, it is the local behavior of the ns-DBD that results in control authority at conditions that are challenging for the majority of active flow control actuators that rely on zero net mass flux momentum addition. The implications of these findings as well as open questions and suggestions for future work are discussed.

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In this paper we discuss the development and implementation of a new Design of Experiment (DoE) experience in the junior-level Thermal-Fluid Systems course. The goal of the DoE is to teach students about dynamic similarity, uncertainty quantification, and technical communications through a hands-on experience with direct connections to real-world applications. In the newly-designed DoE, students must determine whether they can accurately predict pressure drop in real-world pipe systems-including an oil pipeline, a ventilation duct, a natural gas line, and a water supply line-using the equipment we provide. Although the equipment is prescribed, the procedure is not, which has the benefit of minimizing material requirements while allowing students the freedom to pursue a unique approach. The experience is divided into stages with a mixture of individual and group efforts. Students begin by deriving the relevant equations and crafting an experimental procedure as an individual. They then come together in groups of three or four to conduct the experiment and analyze the data, which includes uncertainty quantification. An instructor provides feedback on the data analysis portion before students communicate their results in a short lab report with extensive appendices. Throughout the experience students are required to communicate the limitations of their experiment by quantifying uncertainty and questioning the validity of their assumptions. Overall, the DoE is an exercise in critical thinking, data gathering, analysis, and interpretation of results. We present details of the DoE assignment, assessment of student learning, student feedback from course evaluations, and recommendations for instructors seeking to implement similar projects in their courses.

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