###### Abstract  
This study focuses on the acoustic installation effects that may occur during typical aeroacoustic experiments when the latter are conducted in a closed-vein wind tunnel. More precisely, in regard to the specific problem of airfoil trailing edge noise, an analytical model is derived, which allows predicting the wall-induced reverberation effects that such a noise shall be subjected to, when radiating within a closed-vein, hard-wall, wind tunnel. These effects are then assessed through a parametric investigation so as to characterize their impact on in situ acoustic measurements that would be performed using flush-mounted microphones located on the vein's walls. From a phenomenological perspective, the study highlights how important the reverberation effects by the vein can be. In particular, results reveal how their impact on the noise measurements may greatly vary, depending on the trailing edge noise source location (i.e., the airfoil incidence) and, to a lesser extent, its frequency. The outcomes allow identifying these locations where the installation effects are least, i.e., where to better position a flush-mounted microphone, should in situ noise measurements be conducted. From a methodological viewpoint, the study showcases how the proposed formalism could constitute a simple albeit useful diagnosis tool for mitigating the experimental biases weighing on airfoil trailing edge noise tests to be conducted within closed-vein facilities, whether this would be done a priori by flush-mounting the microphone(s) where these biases are minimal or a posteriori by de-biasing the noise measurements accordingly. a 22 September 202111 October  
or the flow separation occurring in the early stage of stall (as opposed to the deep stall one, which rather results in noise radiating from the entire airfoil). Given its multiple components and complex physics, the airfoil trailing edge (TE) noise is still only partly understood [1; 2; 3], despite half a century of investigations using either experimental [1; 4; 5; 6; 7; 8; 9; 10; 11; 12; 13; 14; 15; 16; 17; 18; 19], theoretical [15; 16; 17; 18; 19], or computational [20; 21; 22; 23; 24; 25] means. Because in situ testing is extremely costly to perform, it is common to characterize aerodynamic noise emissions through small-scale experiments. Traditionally, aeroacoustic tests are conducted within anechoic, open jet wind tunnels, whereas closed-vein installations are rather devoted to pure aerodynamic experiments. Indeed, although closed-vein wind tunnels are known to restitute more accurately the actual flow physics, their confined character incur some unwanted acoustic installation effects, namely, noise reverberation and resonance phenomena due to acoustic backscattering on their walls. It is known, however, that open-jet facilities also come with their own issues, which may complicate (and, in some cases, jeopardize) the experimental characterization and subsequent physical analysis of aeroacoustic phenomena that are sought after. First, open-jet facilities are not entirely free from those side-effects that are commonly attributed to closed-vein wind tunnels, to begin with reverberation issues. Indeed, under some circumstance, the interaction of the noise sources with the experimental apparatus (e.g., mounting side-plates, nozzle, collector) may result in significant acoustic backscattering effects [8; 13; 20; 26; 27; 28]. Alternatively, the interaction between the shear layers generated at the nozzle lips and the mock-up may incur some extraneous noise emission (as clearly pointed out by [PERSON] et al. [8] regarding the well-known airfoil noise experimental campaign by [PERSON] et al. [5]). Even more specific to airfoil noise tests is the fact that, when located within an open jet, a lifting body deflects more importantly the flow streamlines (downwash effect). This results in a modified flow incidence (e.g., effective angle of attack) whose _uncertainty_ can be of several degrees between different apparatus [8; 13].