Prof. Bombardelli's leads a research program which focuses on elucidating
the set of interactions among water turbulence and disperse phases (i.e.,
solid particles and/or bubbles) in multi-phase flows of environmental
importance, including flows such as sediment transport in rivers, lakes and estuaries;
hydraulic jumps; density currents; and bubble plumes, just to mention
a few. His approach is to gain understanding about these flows at different scales by
employing theoretical, numerical and/or experimental techniques, and
field work. This effort is aimed at obtaining better methodologies for
the observation and prediction of a host of environmental problems, including the very challenging
domain of non-dilute flows, i.e., when concentrations of the disperse phase are very high.
Although multi-phase flows have been known for a long time, the theoretical tools
for their analyses have not been made available until recently. Still,
these theories pose serious challenges for their analytical or numerical
treatment; further, their meaning, accuracy and robustness when applied
to solving specific cases is yet to be tested. This already complicated
picture is even more complex given the turbulent nature of most flows.
At present, and despite the progress in recent years, there is no undisputed,
clear explanation for the interactions between sediment particles or
bubbles and water turbulence at small scales. In addition, there are
no universally accepted recipes on how to extrapolate (i.e., to model)
those interactions from the small scales to different larger scales. The possible avenues to solve the puzzle
seem to involve a combination of deterministic and stochastic techniques.
In recent years, Prof. Bombardelli has also devoted efforts to the development of tools for the
verification and validation (V&V) of numerical codes, a very important subject usually overlooked in the development of programs.
(Prof. Bombardelli is scheduled to give a webinar on the subject for ASCE.) Those
tools include analytical solutions and the incorporation of procedures for finding code "bugs."
In addition to the above fundamental investigation, Prof. Bombardelli's group and collaborators
conduct research on California lakes and estuaries. In that line, Prof. Bombardelli has published original work
associated with the phenomenon of sediment resuspension in lakes (Salton Sea), flow and water quality in the Delta
of the Sacramento and San Joaquin Rivers, and the Russian River on the coast. In the case of the Delta, he has explored flow and
water quality issues associated with climate change.
Finally, Prof. Bombardelli undertakes an active expert work for South American countries, namely
Peru and Argentina. In the first case, he worked for the United Nations Office of Projects for Services (2013) and for
Aguas y Saneamiento Argentinos (AySA) of the Argentinian Government (2008, 2010) in a project sponsored by the World Bank.