  Transient processes generally constitute part of energy-system cycles. If
skillfully manipulated, they actually are capable of assisting systems to
behave beneficially to suit designers' needs. In the present study, behaviors
related to both thermal conductivities ($\kappa$) and heat capacities ($c_{v}$)
are analyzed. Along with solutions of the temperature and the flow velocity
obtained by means of theories and simulations, three findings are reported
herein: $(1)$ effective $\kappa$ and effective $c_{v}$ can be controlled to
vary from their intrinsic material-property values to a few orders of magnitude
larger; $(2)$ a parameter, tentatively named as "nonlinear thermal bias", is
identified and can be used as a criterion in estimating energies transferred
into the system during heating processes and effective operating ranges of
system temperatures; $(3)$ When a body of water, such as the immense ocean, is
subject to the boundary condition of cold bottom and hot top, it may be
feasible to manipulate transient behaviors of a solid propeller-like system
such that the system can be turned by a weak buoyancy force, induced by the
top-to-bottom heat conduction through the propeller, provided that the density
of the propeller is selected to be close to that of the water. Such a turning
motion serves both purposes of performing the hydraulic work and increasing the
effective thermal conductivity of the system.
