Filtering analysis of a direct numerical simulation of the turbulent Rayleigh-Benard problem

A filtering analysis of a turbulent flow was developed which provides details of the path of the kinetic energy of the flow from its creation via thermal production to its dissipation. A low-pass spatial filter is used to split the velocity and the temperature field into a filtered component (composed mainly of scales larger than a specific size, nominally the filter width) and a fluctuation component (scales smaller than a specific size). Variables derived from these fields can fall into one of the above two ranges or be composed of a mixture of scales dominated by scales near the specific size. The filter is used to split the kinetic energy equation into three equations corresponding to the three scale ranges described above. The data from a direct simulation of the Rayleigh-Benard problem for conditions where the flow is turbulent are used to calculate the individual terms in the three kinetic energy equations. This is done for a range of filter widths. These results are used to study the spatial location and the scale range of the thermal energy production, the cascading of kinetic energy, the diffusion of kinetic energy, and the energy dissipation. These results are used to evaluate two subgrid models typically used in large-eddy simulations of turbulence. Subgrid models attempt to model the energy below the filter width that is removed by a low-pass filter

Implementation of a fully-balanced periodic tridiagonal solver on a parallel distributed memory architecture

While parallel computers offer significant computational performance, it is generally necessary to evaluate several programming strategies. Two programming strategies for a fairly common problem - a periodic tridiagonal solver - are developed and evaluated. Simple model calculations as well as timing results are presented to evaluate the various strategies. The particular tridiagonal solver evaluated is used in many computational fluid dynamic simulation codes. The feature that makes this algorithm unique is that these simulation codes usually require simultaneous solutions for multiple right-hand-sides (RHS) of the system of equations. Each RHS solutions is independent and thus can be computed in parallel. Thus a Gaussian elimination type algorithm can be used in a parallel computation and the more complicated approaches such as cyclic reduction are not required. The two strategies are a transpose strategy and a distributed solver strategy. For the transpose strategy, the data is moved so that a subset of all the RHS problems is solved on each of the several processors. This usually requires significant data movement between processor memories across a network. The second strategy attempts to have the algorithm allow the data across processor boundaries in a chained manner. This usually requires significantly less data movement. An approach to accomplish this second strategy in a near-perfect load-balanced manner is developed. In addition, an algorithm will be shown to directly transform a sequential Gaussian elimination type algorithm into the parallel chained, load-balanced algorithm

Simulation of the turbulent Rayleigh-Benard problem using a spectral/finite difference technique

The three-dimensional, incompressible Navier-Stokes and energy equations with the Bousinesq assumption have been directly simulated at a Rayleigh number of 3.8 x 10 to the 5th power and a Prandtl number of 0.76. In the vertical direction, wall boundaries were used and in the horizontal, periodic boundary conditions were used. A spectral/finite difference numerical method was used to simulate the flow. The flow at these conditions is turbulent and a sufficiently fine mesh was used to capture all relevant flow scales. The results of the simulation are compared to experimental data to justify the conclusion that the small scale motion is adequately resolved

A programming environment for distributed complex computing. An overview of the Framework for Interdisciplinary Design Optimization (FIDO) project. NASA Langley TOPS exhibit H120b

The Framework for Interdisciplinary Design Optimization (FIDO) is a general programming environment for automating the distribution of complex computing tasks over a networked system of heterogeneous computers. For example, instead of manually passing a complex design problem between its diverse specialty disciplines, the FIDO system provides for automatic interactions between the discipline tasks and facilitates their communications. The FIDO system networks all the computers involved into a distributed heterogeneous computing system, so they have access to centralized data and can work on their parts of the total computation simultaneously in parallel whenever possible. Thus, each computational task can be done by the most appropriate computer. Results can be viewed as they are produced and variables changed manually for steering the process. The software is modular in order to ease migration to new problems: different codes can be substituted for each of the current code modules with little or no effect on the others. The potential for commercial use of FIDO rests in the capability it provides for automatically coordinating diverse computations on a networked system of workstations and computers. For example, FIDO could provide the coordination required for the design of vehicles or electronics or for modeling complex systems

Crow deaths as a sentinel surveillance system for West Nile virus in the northeastern United States, 1999.

In addition to human encephalitis and meningitis cases, the West Nile (WN) virus outbreak in the summer and fall of 1999 in New York State resulted in bird deaths in New York, New Jersey, and Connecticut. From August to December 1999, 295 dead birds were laboratory-confirmed with WN virus infection; 262 (89%) were American Crows (Corvus brachyrhynchos). The New York State Department of Health received reports of 17,339 dead birds, including 5,697 (33%) crows; in Connecticut 1,040 dead crows were reported. Bird deaths were critical in identifying WN virus as the cause of the human outbreak and defining its geographic and temporal limits. If established before a WN virus outbreak, a surveillance system based on bird deaths may provide a sensitive method of detecting WN virus

Part 2: Preparing Entry-Level Occupational and Physical Therapy Students to Promote Healthy Lifestyles Emphasizing Healthy Eating with Individuals with Disabilities

Rehabilitation professionals including occupational therapists (OT) and physical therapists (PT) are increasingly called upon to incorporate health promotion of lifestyle behaviors including physical activity and healthy eating into routine clinical care. While OTs and PTs may be comfortable promoting activity-related behaviors, many are less comfortable with nutrition behaviors. To address entry-level OT and PT students’ perceived discomfort with discussing diet-related behaviors, faculty developed a healthy eating module for students to use during a community-based service learning program. The purpose of this paper is to describe the formative evaluation process of developing the healthy eating module, and to discuss results of a pilot trial of this module. The formative assessment of the healthy eating module consisted of four steps: focus groups with students, key informant interviews with community partners, expert panel round table, and expert panel review of materials. Students (n=117) completed questionnaires at the end of the service learning program to assess how much they used the new resources, and how useful they found the resources. The final healthy eating module consisted of an on-line training session and a healthy eating toolkit, including resources for assessments, treatment activities and additional nutrition information. Mann-Whitney U tests indicated that students who reported high use of materials found the resources significantly more helpful than those students who reported low use (

Part 1: Preparing Entry-Level Occupational Therapy and Physical Therapy Students to Promote Health and Wellbeing with Individuals with Disabilities

To address accreditation standards for health and wellbeing within entry-level occupational therapy (OT) and physical therapy (PT) programs, the OT, PT, and Human Studies Departments at the University of Alabama at Birmingham (UAB) collaborated with community partners to conduct an interdisciplinary service learning activity based on the I Can Do It, You Can Do It Program (ICDI). This program is a structured community health program where individuals without disabilities are partnered with individuals with disabilities to enhance physical activity, healthy eating, and community participation. The purpose of this paper is to describe a formative evaluation of ICDI at UAB, and to discuss revisions to the program made as a result of the evaluation. Faculty used a qualitative design to collect feedback on perceived benefits and challenges of the program. Focus groups were conducted with students who completed the program, and key informant interviews were conducted with site coordinators from each of the three partnering community sites. Two themes emerged from student focus groups: (1) Program benefits, with sub-themes of hands-on application and interaction, and (2) Challenges with suggestions for change, with sub-themes of preparation, communication, and expectations. Four themes emerged from key informant interviews: (1) Students, (2) Logistics, (3) Program benefits, and (4) Transference. Results of this evaluation led to a number of revisions for the 2016 cohort. Future evaluations will include objective measures of change in student knowledge over time, as well as health and behavioral outcomes of community members who participated in the ICDI program at UAB

Green Infrastructure Assessment Tools for Varying Scales in Coastal South Carolina

2010 S.C. water Resources Conference - Science and Policy Challenges for a Sustainable Futur