Proceedings of the 27th National and 5th International ISHMT-ASTFE Heat and Mass Transfer Conference December 14-17, 2023, IIT Patna, Patna-801106, Bihar, India
The Dynamics of Distributed Thermals
摘要
The present study analyses the dynamics of distributed
thermals. The buoyancy is injected into a quiescent water
medium by perturbing the temperature field. Subsequent
temperature and velocity field evolution is obtained through
numerical simulations using the Boussinesq-Fourier model for
incompressible water flow. It is observed that the system
evolves from one form of thermal non-equilibrium state to
another form of thermal non-equilibrium state. A
thermodynamic analysis is also conducted to unveil the
evolution dynamics of distributed thermals. The analysis
uncovers a fundamental aspect postulated here as the
"circulation shaft-work hypothesis." The swirling strengthbased
quantification of circulations finds particular relevance in
this hypothesis. Subsequently, the connection between the
swirling strength and velocity fluctuations is unveiled,
uncovering an inherent length scale that signifies the extent of the circulation regions. The present study believes that the
thermodynamics-based analysis, taking swirling strength into
account, can open up a new paradigm for understanding the
evolution of thermals.