Design tools applied to a trochoidal gear pump
- Autores: Mercedes García Vílchez
- Directores de la Tesis: Pedro Javier Gámez Montero (dir. tes.), Esteban Codina Macia (dir. tes.)
- Lectura: En la Universitat Politècnica de Catalunya (UPC) ( España ) en 2014
- Idioma: inglés
- Tribunal Calificador de la Tesis: Antonio Vernet Peña (presid.), Roberto Castilla López (secret.), Joan Roca Enrich (voc.)
- Materias:
- Enlaces
- Tesis en acceso abierto en: TDX
- Resumen
Positive displacements pumps, as currently designed, produce significant flow pulsations that result in pressure pulsations. These pulsations contribute to the global noise generated by the installation. Moreover, they interact with the system where the pump is connected shortening the life of both the pump and circuit components. Rotary trochoidal gear pump, a type of rotary positive displacement machine, has characteristics that make it suitable for many applications fields. Nowadays, in cases like additivation and dosage, these applications have not been completely developed, and present a growing potential in the industrial world, such as in new diesel engines generation or in medical applications. The thesis presents a set of design tools applied to trochoidal gear pumps, from the viewpoint of the fluid dynamical performance of the pump. These design tools are aimed to help improving two of the main performance indices of the pump: the volumetric capacity and the flow irregularity, leading the designer to more efficient new designs of gerotor pumps. On the one hand, the volumetric capacity is related with the pump's efficiency, and increases in this particular index result in a higher efficiency of the pump. On the other hand, flow irregularity measures de flow ripple generated by the pump, and by reducing this index, the life of both the pump and the installation can be extended, as phenomena like fatigue are attenuated. This is achieved through the use of analytical, simulation and experimental procedures. From the analytical side, two new modules of GeroLAB Package are created, Minimum Clearance Module and Effective Port Areas. Also, a dynamical simulation through BondGraph is conducted, studying the influence of the port areas geometry. In the present thesis, the model has been improved by adding the information of the effective port areas, thus making it more realistic. Regarding the numerical simulation, a three-dimensional with deforming mesh Computational Fluid Dynamics model is presented. The model includes the effects of the manufacturing tolerance and the leakage inside the pump. Also, the influence of simulating the contact points is studied. A new boundary condition is created for the simulation of the solid contact in the interteeth radial clearance, established as a fluid-dynamic condition. The experimental study of the pump is carried out by means of Time-Resolved Particle Image Velocimetry. This technique is developed in order to adapt it to the gerotor pump, and measurements are captures in the outlet pipe and in the chambers between trochoidal profiles. Results are qualitatively evaluated thanks to the analytical and simulation tools. The presented experimental procedure meets the need of a methodology to directly measure the flow ripple generated by the pump, with a non-intrusive technique. It constitutes an alternative to the Secondary Source Method, and it is the first approach of Time-Resolved Particle Image Velocimetry applied to a trochoidal gear pump, according to the author's knowledge.
