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Flow maldistribution across automotive exhaust catalysts significantly affects their conversion efficiency. Flow behaviour can be predicted using computational fluid dynamics (CFD). This study investigates the application of CFD to modelling flow in a 2D system consisting of a catalyst monolith downstream of a wide-angled planar diffuser presented with steady flow. Two distinct approaches, porous medium and individual channels, are used to model monoliths of length 27 mm and 100 mm. Flow predictions are compared to particle image velocimetry (PIV) measurements made in the diffuser and hot wire anemometry (HWA) data taken downstream of the monolith. Both simulations compare favourably with PIV measurements, although the models underestimate the degree of mixing in the shear layer at the periphery of the emerging jet. Tangential velocities are predicted well in the central jet region but are overestimated elsewhere, especially at the closest measured distance, 2.5 mm from the monolith.

The National Science Foundation is responsible for the conduct of the United States National Program in Antarctica under Presidential Memorandum 6646 of February 5, 1982. As such, it supports all U.S. scientific activities in the Antarctic at three major stations (two on the continent, McMurdo and South Pole, and one on the peninsula, Palmer), on two research vessels, and at a number of field camps. Antarctica is a land having no indigenous population. All life support and infrastructure have to be brought in by ship and airplane. South Pole Station depends exclusively on air support, mostly from McMurdo Station which is 800 miles away. In this paper, some of the challenges facing the United States Antarctic Program in this decade are examined. Of great concern is the conduct of the program in an environmentally sound and responsible manner.

The United States Antarctic Program implements the U.S. policy of an active and influential presence in Antarctica. The principal expression of this policy is through the conduct of scientific research. This paper describes recent changes in the logistics structure necessary to support the scientific program. It also describes several improvements in communications, highlights accomplishments of the Antarctic Aeronomy and Astrophysics program, and presents a status report on the South Pole Redevelopment Project.

The principal expression of U.S. Presence in Antarctica is through science. Hence, the United States Antarctic Program (USAP) is run by the National Science Foundation. In the austral summer of 1994-1995 (October-February), the Program supported approximately 120 science projects involving 640 scientists and technicians. This paper highlights some of the recent accomplishments at Amundsen-Scott South Pole Station and discusses the need and prospects for a new station there. It also discusses some successes in the USAP waste management program.

The National Science Foundation (NSF) has responsibility for the management, funding, and operation of the United States Antarctic Program (USAP), the U.S. national research program in Antarctica. The program is multifaceted, having international obligations under the Antarctic Treaty, providing grantees funding for Antarctic scientific research, and providing the necessary operational and logistical support to researchers to execute their programs. The latter includes building, maintaining, and operating all research stations, camps, and other facilities, and operating two research vessels, ski-equipped C-130 airplanes, and helicopters. The paper will examine some of USAP's logistical and operational challenges. For example, for 4 of the last 5 seasons the Program has used U.S. Air Force C-5B airplanes to deliver cargo such as helicopters and Twin Otter airplanes to McMurdo Station sea-ice runway at the beginning of the season. USAP has no concrete runway in Antarctica.

The United States Antarctic Program (USAP) is managed by the National Science Foundation (NSF). NSF supports a number of scientific research programs on the Antarctic continent and the surrounding oceans, including biology, glaciology, aeronomy and astrophysics, earth sciences, and ocean and climate systems. Antarctica is a difficult region to reach. It is an inhospitable place to live. At the same time, it is a nearly pristine, natural scientific laboratory where much about our planet can be learned. NSF supplies all life support and infrastructure for USAP, including two research vessels, a number of seasonal field camps, and three permanent research stations: McMurdo, South Pole, and Palmer. Last year, we presented a paper introducing ICES to Antarctica (SAE Technical Paper #921128). This paper provides updates and explores new areas of the program.