Eventos Anais de eventos
COBEM 2021
26th International Congress of Mechanical Engineering
IMPROVED PRELIMINARY GEOMETRY FOR SCO2 CENTRIFUGAL COMPRESSORS THROUGH FULL 1D MODELING
Submission Author:
Gustavo Singulane Gonçalves , SP , Brazil
Co-Authors:
Gustavo Singulane Gonçalves, Elóy Esteves Gasparin, Vitor Cesar Nogueira Mattos, Paulo Eduardo Batista de Mello, Fabio Saltara, Daniel Dezan, Jurandir Itizo Yanagihara, Leandro Salviano
Presenter: Gustavo Singulane Gonçalves
doi://10.26678/ABCM.COBEM2021.COB2021-2037
Abstract
. In order to extend the life of oil deposits, and therefore the profit from them, a technique called Enhanced Oil Recovery (EOR) can be used. One of the methods for performing this technique is the reinjection of CO2 in the oil reservoir, which not only increases the oilfield life, but also provides a way to permanently sequester carbon dioxide. To accomplish the high pressures required for the reinjection at such depths, supercritical CO2 compressors must be developed. The numerical analysis of the thermal-hydraulic behavior of this equipment usually requires complex and high computational cost for 3D simulations. In order to provide faster and reliable results, a code for the full compressor was written in Python programming language, being an open-source alternative to obtain preliminary results that can provide a starting point for the centrifugal compressor geometry for a 3D design. For a full 1D modeling, a supercritical CO2 centrifugal compressor with impeller, vaneless diffuser and volute is considered. The available 1D models in the literature related to geometry and losses were studied and implemented under hypothesis: steady state, vaneless diffuser, constant passage width in the diffuser, constant angle between tangential, meridional and absolute velocities throughout the diffuser and incompressible flow in the volute. Eight geometrical parameters are submitted to a screening sensitivity analysis method using the 1D model and their impact towards isentropic efficiency, power required and pressure recovery are assessed. A 3D compressor model consisting in impeller and diffuser is simulated, assuming steady state flow, SST k-omega turbulence model and Span and Wagner equation of state. An improved 3D geometry is created based on insight obtained from 1D and 3D evaluations. The 1D model is validated through experimental data and 3D model is used for better understanding of physical phenomena differences between original and improved designs. This methodology can significantly increase the machine performance using relatively low computational resources.
Keywords
Centrifugal Compressor, CFD, One-dimensional model, loss models
