Validación estadística de un modelo de dinámica de fluidos computacional (CFD) optimizado con refinamiento de malla y funciones definidas por el usuario

In common refrigeration systems the energy source required for vapor compression is electricity, while in absorption systems its source is heat. Absorption refrigeration systems have gained ground in recent years, thanks to their low electrical energy consumption, compared to compression refrigeration systems, mainly due to the fact that they use residual thermal energy instead of mechanical energy. (Noriega Sánchez and Pérez Rojas 2011). The absorber absorbs the refrigerant that comes from the evaporator, releasing heat (Fernández 2011), this makes the absorber the "heart" of the refrigeration system. In the last 10 years, there has been a boom in experimental and numerical studies seeking design and operation improvements for this component. One of these tools is called computational fluid dynamics CFD for its acronym in English, which has been used to represent the phenomena of heat and mass transfer within the absorber and its relationship with operating parameters such as pressure, temperature, the concentration and the inflows to the system and outflows from the system. In the present study, the comparison of two CFD models was carried out. of a bubble-type absorber with which the effect of two optimization methods was evaluated: mesh refinement and the use of user-defined functions, comparative statistics and precision test methods were used. The results show that the most sensitive variables of the model are the heat and mass fluxes and that mesh refinement will always be necessary to obtain more accurate results in the model when compared to the experimental results. Reviewing CFD model studies of absorbers reported in the scientific literature, a methodological deficiency was observed in the validation of the models that does not allow to conclude statistically, if the optimizations with mesh refinement and the functions defined by the user improve their performance or not, the purpose of the investigation is to make a statistical comparison and evaluate its effectiveness when performing mesh modeling, with models from other studies and carried out. Obtaining as a result that the greater the number of elements in the mesh, it means that in the four variables (total concentration of ammonium at the outlet of the internal tube, temperature of the solution at the outlet of the internal tube and heat flux transferred from the solution and Flux of ammonium absorbed by the solution) minimize their percentage of error, thus being able to raise the acceptability rates to search for an optimal model, in this type of absorbers, making it more efficient. It is then that there is a need to always evaluate with the four variables, with an optimized system of 250,000 elements in the mesh

• Autores: Charris, Kevin; Castañeda, Juan Pablo
• Tipo de recurso: Trabajo de grado de pregrado
• Fecha de publicación: 2022
• Institución: Corporación Universidad de la Costa
• Repositorio: REDICUC - Repositorio CUC
• Idioma: spa
• OAI Identifier: oai:repositorio.cuc.edu.co:11323/9403
• Acceso en línea: https://hdl.handle.net/11323/9403; https://repositorio.cuc.edu.co/
• Palabra clave: absorbe; CFD; optimization; mesh; cooling; absorbedor; optimización; malla; refrigeración
• Rights: openAccess
• License: Atribución-NoComercial-CompartirIgual 4.0 Internacional (CC BY-NC-SA 4.0)