3D Printed Pressure Anemometers

Abstract

Abstract

Pressure anemometers suitable for fabrication by 3D printing employing fused deposition modeling (FDM) technology were designed, built, and tested in a wind tunnel, the work being initiated by attempting to create a particular type of this class of instruments, commonly known as a Pitot tube. After initial issues due to the porosity of the parts, a consequence of the FDM technique, and difficulties in clearing the interior of the probes after manufacturing, a suitable design solution was achieved, with the results from the 3D printed probe being finally identical to those of a standard reference metallic Pitot tube at the investigated airspeed range of 2.1–31.5 m/s. Exploiting the freedom of form that 3D printing allows, several special-shaped pressure anemometer geometries were designed, with the intent of increasing the pressure signal outputted from the probes to achieve a better measurement precision, particularly at low air speeds. In the process of shape exploration of the pressure enhancing probes, computational fluid dynamics experiments were performed to give insights on suitable designs. The special-shaped pressure probes were tested at speeds ranging from 2.2 to 10.4 m/s, with the maximum pressure signal amplification being obtained by a 3D printed Pitot tube of basic conventional geometry equipped with 3D printed add-on parts. This result is relevant as it shows that existing Pitot tubes of traditional metallic construction can have their pressure output enhanced with the installation of bespoke fabricated 3D printed add-on parts. Although 3D printing did not prove to be particularly advantageous to fabricate simple Pitot tubes, special-purpose complex-shaped pressure anemometers can strongly benefit from this technology due to the freedom of shape design at no extra cost that it allows.