Single-phase and two-phase secondary coolants: simulation and evaluation of their thermophysical properties

• Autor(a) principal: Medeiros, Pedro Samuel Gomes
• Data de Publicação: 2011
• Outros Autores: Barbosa, Cleiton Rubens Formiga, Fontes, Francisco de Assis Oliveira
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Repositório Institucional da UFRN
• Texto Completo: https://repositorio.ufrn.br/handle/123456789/45343
• topic: Ice Slurry; Secondary Fluids; Thermophysical Properties; Thermal Storage Cooling

This paper makes a comparative analysis of the thermophysical properties of ice slurry with conventional single-phase secondary fluids used in thermal storage cooling systems. The ice slurry is a two-phase fluid consisting of water, antifreeze and ice crystals. It is a new technology that has shown great energy potential. In addition to transporting energy as a heat transfer fluid, it has thermal storage properties due to the presence of ice, storing coolness by latent heat of fusion. The single-phase fluids analyzed are water-NaCl and water-propylene glycol solutions, which also operate as carrier fluids in ice slurry. The presence of ice changes the thermophysical properties of aqueous solutions and a number of these properties were determined: density, thermal conductivity and dynamic viscosity. Data were obtained by software simulation. The results show that the presence of 10% by weight of ice provides a significant increase in thermal conductivity and dynamic viscosity, without causing changes in density. The rheological behavior of ice slurries, associated with its high viscosity, requires higher pumping power; however, this was not significant because higher thermal onductivity allows a lower mass flow rate without the use of larger pumps. Thus, the ice slurry ensures its high potential as a secondary fluid in thermal storage cooling systems, proving to be more efficient than single-phase secondary fluids