SPECIAL PHYSICAL MATHEMATICS SEMINAR


TOPIC:		TURBULENT PLUMES IN THE ENVIRONMENT:
		THE CRUCIAL IMPORTANCE OF SOURCE CONDITIONS


SPEAKER:	DR. COLM CAULFIELD
		Department of Mechanical and Aerospace Engineering
		University of California, San Diego

ABSTRACT:

Turbulent isolated sources of fluid of different density appear in a wide
range of circumstances of geophysical, industrial and environmental
interest. Examples in open flows include volcanic eruption clouds, forest
fires and sewage outflows. Turbulent plumes also occur in enclosed spaces,
(e.g. gas leaks, house fires, air conditioners and forced air heating). In
this talk, I shall review bulk models that describe the behavior of such
plumes accurately over a broad range of scales, and then discuss recent
developments that improve the applicability of these models to several
relevant environmental processes.

Particular attention will be given to:

1.	the effect of non-monotonic density variation due to thermal
	expansion as may occur near the vent during volcanic eruptions;

2.	the effect of varying ambient stratification, as often occurs in the
	atmosphere;

3.	the effect of finite fluxes of mass and momentum at the source in an
	enclosed space.

DATE:		FRIDAY, MAY 5, 2000

TIME:		2:30 PM

LOCATION:	Building 2, Room 338

Refreshments will be served at 3:30 in Room 2-349.

						Massachusetts Institute of Technology
						Department of Mathematics
						Cambridge, MA  02139