CFD modelling of the ammonia vapour absorption in a tubular bubble absorber with NH3/LiNO3

The absorber is a key component of absorption cooling systems, and its further development is essential to reduce the size and costs and facilitate the diffusion of absorption cooling systems. Computational fluid dynamics (CFD) can facilitate the characterization of the equipment used in absorption...

Full description

Autores:
Zapata, Andrés
Amaris, Carlos
Sagastume, Alexis
Rodríguez, Andrés
Tipo de recurso:
Article of journal
Fecha de publicación:
2021
Institución:
Corporación Universidad de la Costa
Repositorio:
REDICUC - Repositorio CUC
Idioma:
eng
OAI Identifier:
oai:repositorio.cuc.edu.co:11323/8771
Acceso en línea:
https://hdl.handle.net/11323/8771
https://doi.org/10.1016/j.csite.2021.101311
https://repositorio.cuc.edu.co/
Palabra clave:
CFD
Heat and mass transfer
Absorption refrigeration system
Bubble absorber
Ammonia
Lithium nitrate
Rights
openAccess
License
CC0 1.0 Universal
Description
Summary:The absorber is a key component of absorption cooling systems, and its further development is essential to reduce the size and costs and facilitate the diffusion of absorption cooling systems. Computational fluid dynamics (CFD) can facilitate the characterization of the equipment used in absorption cooling systems at lower costs and complexity, but they must be properly developed and validated to provide reliability. This study provides a detailed description and assessment of a 3D CFD bubble absorber model developed to simulate the absorption process in a vertical double pipe with the NH3/LiNO3 solution. It includes a comprehensive methodology to develop the CFD model and its validation considering the effect of the solution flow and the cooling water temperature on absorber performance parameters such as the absorption mass flux and the solution heat transfer coefficient. The results show that the ‘Volume of Fluid model’ and the ‘Realizable k-epsilon model’ provide the lowest residuals and computational times in the simulations while a good correspondence between the CFD model and the experimental data with errors below 10% and 7% for the absorption mass flux and solution heat transfer coefficient, respectively, was obtained. The maximum absorption rate and heat transfer coefficient were 0.00441 kg m−2 s−1 and 786 W m−2 K−1, respectively.