Propulsion/airframe interference for ducted propfan engines with ground effect

The advanced propfan propulsion systems design of the next-generation subsonic transport aircraft has been of interest to many airline companies in the past several years. This is due to the studies which indicate that an efficient ducted propfan engine technology offers a significant reduction in aircraft fuel consumption. However, because of the geometric complexity of the configuration, one challenge is the integration of the ducted propfan engine with the airframe so that aerodynamic interference effects frequently encountered near the nacelle can be minimized, or perhaps, optimized. To understand this interaction phenomenon better, it is desirable to have a reliable and efficient computational tool that can predict propeller effects on the flowfield around complex configurations

Combining Computational Fluid Dynamics and Agent-Based Modeling: A New Approach to Evacuation Planning

We introduce a novel hybrid of two fields—Computational Fluid Dynamics (CFD) and Agent-Based Modeling (ABM)—as a powerful new technique for urban evacuation planning. CFD is a predominant technique for modeling airborne transport of contaminants, while ABM is a powerful approach for modeling social dynamics in populations of adaptive individuals. The hybrid CFD-ABM method is capable of simulating how large, spatially-distributed populations might respond to a physically realistic contaminant plume. We demonstrate the overall feasibility of CFD-ABM evacuation design, using the case of a hypothetical aerosol release in Los Angeles to explore potential effectiveness of various policy regimes. We conclude by arguing that this new approach can be powerfully applied to arbitrary population centers, offering an unprecedented preparedness and catastrophic event response tool

Cost curves as a function of SIP compliance level for varying building permeability.

<p>Cost curves as a function of SIP compliance level for varying building permeability.</p

Cost metric.

<p>Cost metric.</p

Temperature error in digital bathythermograph data

234-236Simultaneous Digital Bathythermograph (DBT) and Nansen Cast data collected during two cruises of R.V. Gaveshani (GV-117 and GV-118) and archived in Indian Oceanographic Data Centre (IODC) are used to determine existing temperature errors in DBT. The resulting mean error for DBT data from the GV-117 cruise varies from -0.5 to - 1 oC, while it varied between -0.3 and -0.6 oC for data from cruise GV-118. For both the data sets, the error shows consistently negative bias from surface to 800 m depth, however there is no apparent or measurable systematic dependence of the error on depth. Considering the given temperature accuracy of 0.05 oC, the observed DBT error, varying from -0.3 to -1 oC, is significant and such offsets should be removed from DBT archives. It is found that a corrective measure of +0.5 oC, equivalent to the mean surface offset obtained from two cruises, can considerably reduce the temperature error at all DBT depths

Model snapshot with buildings as reflective polygons, the plume as a translucent red cloud and agents (vehicles) as spheres color-coded by speed.

<p>To view a full animation, see: <a href="http://www.utc.edu/Research/SimCenter/agent.php" target="_blank">http://www.utc.edu/Research/SimCenter/agent.php</a>.</p