Use of the Gibbs thermodynamic potential to express the equation of state in atmospheric models
Thuburn, J
Date: 27 February 2017
Journal
Quarterly Journal of the Royal Meteorological Society
Publisher
Wiley / Royal Meteorological Society
Publisher DOI
Related links
Abstract
The thermodynamics of moist processes is complicated, and in typical atmospheric
models numerous approximations are made. However, they are not always made in a
self-consistent way, which could lead to spurious sources or sinks of energy and entropy.
One way to ensure self-consistency is to derive all thermodynamic quantities from ...
The thermodynamics of moist processes is complicated, and in typical atmospheric
models numerous approximations are made. However, they are not always made in a
self-consistent way, which could lead to spurious sources or sinks of energy and entropy.
One way to ensure self-consistency is to derive all thermodynamic quantities from a
thermodynamic potential such as the Gibbs function. Approximations may be made to
the Gibbs function; these approximations are inherited by all derived quantities in a
way that guarantees self-consistency. Here, the feasibility of using the Gibbs function
in an atmospheric model is demonstrated through the development of a semi-implicit,
semi-Lagrangian vertical slice model, and its application to a standard buoyant bubble
test case. The flexibility of the approach is also demonstrated by running the test
case with four different equations of state corresponding to dry air, moist air that
is saturated, a pseudo-incompressible fluid, and an incompressible fluid. A recently
presented ‘blended’ equation set that unifies the dry fully compressible case and the
pseudo-incompressible case is also easily accommodated.
Mathematics and Statistics
Faculty of Environment, Science and Economy
Item views 0
Full item downloads 0