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Raul Morin, author of 'Among the Valiant' shakes hands with Dr. Hector P. Garcia (photograph)
No full text(L. to R.): Raul Morin, author of 'Among the Valiant' shakes hands with Dr. Hector P. Garcia
Correspondence between Antonio R. Martin, Consul of Spain to Hector Hayashi, September 21, 1944
No full textIn this group of correspondence, Hector Haruo Hayashi, a national of Japan, who was living first in an internment camp in Idaho and later in Santa Fe, New Mexico, is owed money from the government of Peru. Hayashi's son, Jorge Hayashi writes on behalf of his father about this money. An official response is sent to both Hector and Jorge Hayashi regarding the payment.Collection of notes, articles, correspondence, photographs, and term papers collected by Yukio Mochizuki, a student at CSU Dominguez Hills, while researching Japanese American incarceration and Japanese Peruvian internment during World War II
Hector McCrimmon
No full textPhotograph - Hector McCrimmon in a railroad crew. Colinton, Alberta. He is the first in the second row holding a do
The computation of unsteady turbulent flow structures in rotating cavities
No full textFlows inside rotating cavities are relevant to geophysical flows, flows in cavities between turbine discs and flows inside computer disc drives. They have consequently been the subject of many investigations. As can be seen in Owen and Rogers1, most experimental and computational studies of cavities such as the ones in Figure 1, have assumed that flow conditions remain steady and axi-symmetric. Recent numerical studies of laminar flows in co-rotating cavities, Tucker and Long2 and also flow visualisation studies of turbulent flows in rotor-stator systems, Figure 1a, Czarny et al3, show that large-scale 3-D and unsteady structures are also present.This study explores whether economical, relative to LES, unsteady RANS methods, can be used to capture these unsteady, 3-D features. A set of 3-D unsteady flow computations has been produced, for the three cases shown in Figure 1; rotor-stator cavities, co-rotating cavities with a stationary outer shroud and also counter-rotating cavities. To minimize grid requirements, the high-Reynolds-number k- model has been employed. For wall boundary conditions instead of the conventional, log-law-based, wall function, a more advanced, analytical wall function of Craft et al4, extended to 3-D, general-geometry flow solvers, is used. The paper will focus on the co- and counter-rotating cavities. It will show that the high-Re k- with the analytical wall-function, as shown in Figure 2 for the co-rotating case, returns 3-D unsteady flow structures. Comparisons with measured time-averaged velocity profiles will be included as well as frequency spectra of the velocity and pressure fluctuations. Flow animations resulting from this work can be accessed from http://tmgflows.mace.manchester.ac.uk/. 1 J.M. Owen and R.H. Rogers.. John Wiley & Sons, 1989. 2P.G. Tucker and C.A. Long. Int. Comm. Heat Mass Transfer, 22(5):639648, 1995. 3O. Czarny, H. Iacovides and B. E. Launder, Fl., Turb. & Comb., Vol 69,pp 51-61, 2002. 4T. J. Craft, A Gerasimov, H. Iacovides and B.E. Launder, Int. J. of Heat and Fl. Flow, 23, 148-16,200
The computation of unsteady turbulent flow structures in rotating cavities
No full textFlows inside rotating cavities are relevant to geophysical flows, flows in cavities between turbine discs and flows inside computer disc drives. They have consequently been the subject of many investigations. As can be seen in Owen and Rogers1, most experimental and computational studies of cavities such as the ones in Figure 1, have assumed that flow conditions remain steady and axi-symmetric. Recent numerical studies of laminar flows in co-rotating cavities, Tucker and Long2 and also flow visualisation studies of turbulent flows in rotor-stator systems, Figure 1a, Czarny et al3, show that large-scale 3-D and unsteady structures are also present.This study explores whether economical, relative to LES, unsteady RANS methods, can be used to capture these unsteady, 3-D features. A set of 3-D unsteady flow computations has been produced, for the three cases shown in Figure 1; rotor-stator cavities, co-rotating cavities with a stationary outer shroud and also counter-rotating cavities. To minimize grid requirements, the high-Reynolds-number k- model has been employed. For wall boundary conditions instead of the conventional, log-law-based, wall function, a more advanced, analytical wall function of Craft et al4, extended to 3-D, general-geometry flow solvers, is used. The paper will focus on the co- and counter-rotating cavities. It will show that the high-Re k- with the analytical wall-function, as shown in Figure 2 for the co-rotating case, returns 3-D unsteady flow structures. Comparisons with measured time-averaged velocity profiles will be included as well as frequency spectra of the velocity and pressure fluctuations. Flow animations resulting from this work can be accessed from http://tmgflows.mace.manchester.ac.uk/. 1 J.M. Owen and R.H. Rogers.. John Wiley & Sons, 1989. 2P.G. Tucker and C.A. Long. Int. Comm. Heat Mass Transfer, 22(5):639648, 1995. 3O. Czarny, H. Iacovides and B. E. Launder, Fl., Turb. & Comb., Vol 69,pp 51-61, 2002. 4T. J. Craft, A Gerasimov, H. Iacovides and B.E. Launder, Int. J. of Heat and Fl. Flow, 23, 148-16,200
Hector Postigo: The Digital Rights Movement [Audio interview]
No full textHector Postigo is the author of The Digital Rights Movement: The Role of Technology in Subverting Digital Copyright, in which he presents three case studies of a broad group of loosely knit organizations and individuals that address issues concerning fair use, free speech, privacy, and innovation in the digital environment. None of these concerns are new but the digital medium has changed the social, legal, and economic configuration in which the stakeholders operate. Users are no longer simply passive receivers of content but producers as well. Anyone with a computer can generate new and original online content, or can reuse and remix content in creative ways. This is a real watershed for creation and innovation and the digital rights movement is motivated by a vision of culture as shared and participatory. Expanded conceptions of fair use and free speech are essential to facilitate this vision. Individuals, organizations, and businesses that “own” content through government-granted copyrights have an interest in maintaining control in their works, for commercial and other reasons. The lines dividing users, creators, and content owners are very fluid, so much of this story is about the evolution of legal rules – government regulation – with regards to copyright and digital technology. By looking at three different cases in which the nascent digital rights movement struggled with the owners and producers of technology and commercial media over the meaning of fair use, free speech, and cultural production, Hector Postigo provides a unique perspective on the profound changes that digital technology has set in motion for cultures, economies, and polities. Fred Rowland interviewed Hector Postigo on December 12, 2013.Klein College of Media and CommunicationTemple University. LibrariesMedia Studies and ProductionLearning and Research ServicesAudacityAudacit
The Computation of Buoyant Flows in Differentially Heated Cavities
No full textatural convection flows are often encountered both in nature and also in engineering applications. Turbulent natural convection flows, even in geometrically simple systems, can be physically very complex. The buoyant force, depending on the orientation of the temperature gradients, can either enhance or suppress turbulence. Earlier numerical studies of such flows, based on RANS1, found it necessary to use low-Reynolds-number models of turbulence, which need fine near-wall grids. This study explores the potential of a recently developed wall-function strategy for the economical and reliable prediction of natural convection flows. This strategy, AWF2, involves the use of large near-wall control volumes and the analytical solution of boundary-layer forms of the momentum and enthalpy equations, to provide wall boundary conditions for momentum, temperature and the turbulence parameters. The conventional wall-function strategy, based on the log-law, is also used for base-line comparisons The turbulent stresses are approximated through high-Reynolds- number turbulence models, which include the k- and 2nd-moment closures. In 2nd-moment closures, elaborate, approximations are employed for the modeling of the turbulent heat fluxes. extending to solution of equations for the temperature fluctuation and its dissipation rate. The proposed paper will include comparisons between RANS predictions that result from the use ofthese models and experimental data, for several cavities. One case is that of a square cavity3 with differentially heated vertical walls, Fig. 1. Nusselt number comparisons, such as those of Fig. 2, suggest that as theAWF provides a cost-effective alrernative to low-Reynolds number models. b1 Ince N Z and Launder B E, Int. Journal of Heat and Fluid Flow, 10, Np 2, pp 110-117, 1989 2 Craft T. J., Gerasimov A V, Iacovides H. and Launder B.E., International Journal of Heat and Fluid Flow, 23, 148-16,2002 3Ampofo, F. and Karayiannis, T.G., Int. J. of Heat and Mass Transfer 46, pp. 35513572, 2003
The computation of unsteady turbulent flow structures in rotating cavities
No full textFlows inside rotating cavities are relevant to geophysical flows, flows in cavities between turbine discs and flows inside computer disc drives. They have consequently been the subject of many investigations. As can be seen in Owen and Rogers1, most experimental and computational studies of cavities such as the ones in Figure 1, have assumed that flow conditions remain steady and axi-symmetric. Recent numerical studies of laminar flows in co-rotating cavities, Tucker and Long2 and also flow visualisation studies of turbulent flows in rotor-stator systems, Figure 1a, Czarny et al3, show that large-scale 3-D and unsteady structures are also present.This study explores whether economical, relative to LES, unsteady RANS methods, can be used to capture these unsteady, 3-D features. A set of 3-D unsteady flow computations has been produced, for the three cases shown in Figure 1; rotor-stator cavities, co-rotating cavities with a stationary outer shroud and also counter-rotating cavities. To minimize grid requirements, the high-Reynolds-number k- model has been employed. For wall boundary conditions instead of the conventional, log-law-based, wall function, a more advanced, analytical wall function of Craft et al4, extended to 3-D, general-geometry flow solvers, is used. The paper will focus on the co- and counter-rotating cavities. It will show that the high-Re k- with the analytical wall-function, as shown in Figure 2 for the co-rotating case, returns 3-D unsteady flow structures. Comparisons with measured time-averaged velocity profiles will be included as well as frequency spectra of the velocity and pressure fluctuations. Flow animations resulting from this work can be accessed from http://tmgflows.mace.manchester.ac.uk/. 1 J.M. Owen and R.H. Rogers.. John Wiley & Sons, 1989. 2P.G. Tucker and C.A. Long. Int. Comm. Heat Mass Transfer, 22(5):639648, 1995. 3O. Czarny, H. Iacovides and B. E. Launder, Fl., Turb. & Comb., Vol 69,pp 51-61, 2002. 4T. J. Craft, A Gerasimov, H. Iacovides and B.E. Launder, Int. J. of Heat and Fl. Flow, 23, 148-16,200
Convective heat transfer in pulsed separated flows
No full textThe present paper describes the numerical modelling of turbulent flow and convective heat transfer for two cases of forced unsteady separated flows: periodically oscillating flow through an abrupt pipe expansion, and flow over a backward facing step with periodic injection and ingestion through a slot at the separation corner. In both cases the flow Reynolds numbers are reasonably high and emphasis is placed on the resulting heat transfer rates in the separated and recovery regions of the flow. The present work tests the two-equation linear k -e scheme (Launder and Sharma, 1974) ; a modified two-equation non-linear k -e (Craft et al., 2005), and a simple DSM model (Iacovides et al., 1999) in conjunction with the Reynolds-averaged momentum (URANS) and temperature equations. The Crank-Nicholson and bounded QUICK schemes have been used in all computations and tests were carried out to ensure grid and time-step independency of the results. The imposed unsteadiness enhances the coherence of the separated shear layers and reduces the reattachment lengths. All the models are shown to broadly capture this effect, with the non-linear eddy viscosity scheme giving better quantitative agreement with available experimental data. Key words: Eddy-viscosity model, DSM, Convective heat transfer, Imposed unsteadiness, URANS
Convective heat transfer in pulsed separated flows
No full textThe present paper describes the numerical modelling of turbulent flow and convective heat transfer for two cases of forced unsteady separated flows: periodically oscillating flow through an abrupt pipe expansion, and flow over a backward facing step with periodic injection and ingestion through a slot at the separation corner. In both cases the flow Reynolds numbers are reasonably high and emphasis is placed on the resulting heat transfer rates in the separated and recovery regions of the flow. The present work tests the two-equation linear k -e scheme (Launder and Sharma, 1974) ; a modified two-equation non-linear k -e (Craft et al., 2005), and a simple DSM model (Iacovides et al., 1999) in conjunction with the Reynolds-averaged momentum (URANS) and temperature equations. The Crank-Nicholson and bounded QUICK schemes have been used in all computations and tests were carried out to ensure grid and time-step independency of the results. The imposed unsteadiness enhances the coherence of the separated shear layers and reduces the reattachment lengths. All the models are shown to broadly capture this effect, with the non-linear eddy viscosity scheme giving better quantitative agreement with available experimental data. Key words: Eddy-viscosity model, DSM, Convective heat transfer, Imposed unsteadiness, URANS
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