CFD optimization of an immersed particle heat exchanger

Crude oil direct fired furnace model

“…There are many different models based on finite element approximations or computational fluid dynamics (CFD), which have been developed and used for heater furnace design and analysis. The CFD models are employed in many different applications such as simulating the process flow phase changes inside tubular passes [7], investigating heat distribution inside furnaces at different operating conditions [8], simulate fouling and analyzing its effects on heat transfer [9], study the effects of changing components' location and design dimensions on the system performance improvement [10] and so on. These models are generally presented in the form of partial differential equations that have been solved with respect to boundary and initial conditions [11].…”

High Temperature Gas-to-Gas Heat Exchanger Based on a Solid Intermediate Medium

“…This task was not studied in this work. A general methodology for approaching this problem, based on design optimization techniques, was proposed by De Bellis and Catalano [18] and applied to a particular geometrical configuration. However, that geometry configuration dealt with a gas mass flow rate that was very low; hence, inlet and outlet pipes were optimized for a very small size column.…”

Analysis of the complementary energy losses of a high temperature gas to gas heat exchanger based on a solid intermediate medium

“…Some of the authors have recently proposed and optimized [8][9][10] an innovative Immersed Particle Heat Exchanger, which employs an intermediate medium with high thermal capacity: with reference to Figure 1, small alumina particles fall in a column where hot gas, coming from a separate combustion chamber (external combustion gas turbine) or from turbine outlet (heat recovery cycle), flows from the bottom to the top; the warmed up particles are then collected at the bottom of the column and inserted at the top of a second column where they transfer the accumulated heat to a counter-flowing cold gas. Cold particles are collected at the bottom of the second module and delivered back at the top of the plant by the conveyor.…”

“…It is noteworthy that, due to the small particle size, conduction inside the intermediate medium can be neglected, as demonstrated in [10] by means of DNS simulations. The experimental facility was also equipped with a second vertical pipe, used to demonstrate that very fine particles, which could damage turbine blades in a real plant, can be completely eliminated by means of centrifugation [8,9]. In addition, a tri-dimensional CFD model, capable of recognizing all 3D geometrical details, was developed and used to optimize the main geometrical parameters affecting the heat exchange effectiveness [9].…”

“…The experimental facility was also equipped with a second vertical pipe, used to demonstrate that very fine particles, which could damage turbine blades in a real plant, can be completely eliminated by means of centrifugation [8,9]. In addition, a tri-dimensional CFD model, capable of recognizing all 3D geometrical details, was developed and used to optimize the main geometrical parameters affecting the heat exchange effectiveness [9]. A mechanical system interposed between the two columns is needed to pressurize the solid intermediate medium; afterwards, the particles can fall in the second column thanks to gravity.…”