1 research outputs found
Mixing Due to Natural Convection in a Hydrothermal Reactor: A CFD Study
The successful design of biomass
hydrothermal reactors could be
substantially enhanced by computational fluid dynamics (CFD) simulations.
However, their performance is still limited by the complexity of the
involved physicochemical phenomena and the scarcity of experimental
data. This study employs such simulations to analyze the thermo-fluid
dynamics of an unstirred batch hydrothermal reactor. By assessing
the reactor’s response to a lateral heat source, we show that
correctly including various phenomena, such as phase transfers and
temperature-dependent properties, enables accurate reproduction of
natural convection, providing a more solid base for CFD studies on
hydrothermal units. The results provide valuable insights into the
reactor’s inner mixing, which for pure water appears adequate
despite the absence of stirring. Additionally, we explore two approaches
to include a biomass fixed bed or a non-Newtonian sludge. Discussing
future efforts needed to make the simulation of such media more established,
we show that their presence may indeed hinder mixing, with implications
for the products’ quality and safety and for hydrothermal processing
control and design