Determination of aerodynamic drag coefficients using a drop test with a wireless accelerometer and its application to model rockets

Artikel i vetenskaplig tidskrift, 2019

The use of drag coefficients to quantify the drag force on objects moving through air is a key concept in aerodynamics. However, gaining access to a wind tunnel, the conventionally used apparatus with which to measure drag coefficients, can be difficult for students and educators at the undergraduate level. Several methods have been proposed as alternatives to the wind tunnel, but these often suffer from experimental complexity. In this paper, we propose a straightforward method using a wireless accelerometer to eliminate several common drawbacks of previous methods, enabling a simpler and direct analysis of drag. Here, we describe the method and its validation along with an application to model rockets as a possible undergraduate laboratory experiment. We also discuss an inconsistency regarding the drag coefficient of a typical model rocket and use it as an example of not taking published results at face value.