Gear pumps are the most versatile models of hydraulic equipment intended for the generation of hydraulic energy. Their widespread use in various industrial applications is due to their low cost, ease of handling and constructional simplicity. This article investigates the volumetric flow produced by an external gear pump driven by an electric motor that plays the role of a wind rotor. This pump was made using additive technologies, which further reduces its production cost and facilitates the decommissioning process. Determining this flow is extremely important for establishing the functional parameters of the pump when they are not known. In this regard, a simplified model of gear pump was designed and created with the Autodesk Inventor design software. The volumetric flow depends on the volume of fluid found in the empty spaces between the teeth. To make these determinations, image processing and performing a CFD simulation are proposed to validate the results.