Aerodynamic interaction between vortical wakes and lifting two-dimensional bodies

Unsteady rotor wake interactions with the empennage, tail boom, and other aerodynamic surfaces of a helicopter have a significant influence on its aerodynamic performance, the ride quality, and vibration. A numerical method for computing the aerodynamic interaction between an interacting vortex wake and the viscous flow about arbitrary two-dimensional bodies was developed to address this helicopter problem. The method solves for the flow field velocities on a body-fitted computational mesh using finite-difference techniques. The interacting vortex wake is represented by an array of discrete vortices which, in turn, are represented by a finite-core model. The evolution of the interacting vortex wake is calculated by Lagrangian techniques. The viscous flow field of the two-dimensional body is calculated on an Eulerian grid. The flow around circular and elliptic cylinders in the absence of an interacting vortex wake was calculated. These results compare very well with other numerical results and with results obtained from experiment and thereby demonstrate the accuracy of the viscous solution. The interaction of a rotor wake with the flow about a 4 to 1 elliptic cylinder at 45 degree incidence was calculated for a Reynolds number of 3000. The results demonstrate the significant variations in the lift and drag on the elliptic cylinder in the presence of the interacting rotor wake

Thin plastic sheet eliminates need for expensive plating

Gasket of a commercially available plastic material is interposed between the mating surfaces in axial joints where a hard and a soft metal are in intimate contact under stress conditions. This eliminates the fretting problem and is quicker and less expensive than the plating process

The calculation of rotor/fuselage interaction for two-dimensional bodies

Unsteady rotor wake interactions with the empennage, tail boom, and other aerodynamic surfaces have a significant influence on the aerodynamic performance of the helicopter, ride quality, and vibration. A Computational Fluid Dynamic (CFD) method for computing the aerodynamic interaction between an interacting vortex wake and the viscous flow about arbitrary 2-D bodies was developed to address this helicopter problem. The vorticity and flow field velocities are calculated on a body-fitted computational mesh using an uncoupled iterative solution. The interacting vortex wake is represented by an array of discrete vortices which, in turn, are represented by a finite core model. The evolution of the interacting vortex wake is calculated by Lagrangian techniques. The flow around circular and elliptic cylinders in the absence of an interacting vortex wake was calculated. These results compare very well with other numerical results and with results obtained from experiment and thereby demonstrate the accuracy of the viscous solution. The interaction of a simulated rotor wake with the flow about 2-D bodies, representing cross sections of fuselage components, was calculated to address the vortex interaction problem. The vortex interaction was calculated for the flow about a circular and an elliptic cylinder at 45 and 90 degrees incidence. The results demonstrate the significant variation in lift and drag on the 2-D bodies during the vortex interaction

Achievement in Physical Science in Relation To The Type of High School Attended

Certain standards set up oy the State Board of Education upon the recommendation of the State Superintendent of Public Instruction must be met by a class “ A” , “ B “ or C school. Administrators in class A and B high schools are required to hold a Kansas administrator\u27s certificate, and this requirement must also be met by all administrators in class C schools by September 1 , 1952. At the present time, teachers in class “ A” schools must have at least fifteen semester hours of preparation in a teaching field , in class B schools at least twelve hours , and in class C schools at least eight hours. The general public and many educators seemingly are of the opinion that student achievement is scholastically better in a class A high school than in a class B high school, and in a class B high school better than in a class C\u27\u27 high school. A knowledge of the standards for classifying high schools by the State of Kansas leads the reader to a like conclusion. Actually, does any real difference of achievement exist among these three classes of high schools in Kansas? In particular , is there a significant difference of achievement in physical science among our Kansas secondary school graduates according to the t:ype of school attended? In order to answer this second question the writer undertook to find the differences, if any , in achievement of students in class A , B and C high schools in the state of Kansas , as measured by the attainment of students who took a physical science entrance examination at the Fort Hays Kansas State College at Hays, Kansas. As a corollary to the main problem just stated, attention was also given relative to physical science courses taken in high school by the students included in this study

O sistema magmático do depósito Cu-Mo tipo Pórfiro Pancho Árias, Cordilheira Oriental, Argentina

Dissertação (mestrado) — Universidade de Brasília, Instituto de Geociências, Programa de Pós-Graduação em Geociências Aplicadas, 2017.O depósito Cu-Mo Pancho Árias localiza-se na Cordilheira Oriental dos Andes Centrais argentinos, é o membro mais antigo do complexo magmático Las Burras-Almagro-El Toro, que constituí um dos corpos ígneos terciários localizados no lineamento Calama-Olacapato-El Toro. A área hospeda quatro membros magmáticos intrusivos em um embasamento metassedimentar neoproterozoico. Esses membros são dois pórfiros andesíticos, um stock de composição quartzo-monzodiorito e um sistema de diques e sills riodacíticos a traqui-andesíticos. Ocorrem corpos de brechas ligados aos pórfiros andesíticos, e ao stock. A localização no depósito, bem como as texturas e composições nos permitiram individualizar seis corpos de brechas, as quais são dos tipos polimíticas e monomíticas, em arranjo que podem ser tanto matriz como fragmento suportado. Em geral, as brechas do setor centro-nordeste hospedam a parte da mineralização em Cu, a qual é formada por cristais de calcopirita parcialmente substituídos por covelita. Porém, a mineralização também se estende às rochas encaixantes aprisionada em vênulas e estruturas stockwork. Nessa situação, o predomínio da mineralização é em Mo e ocorre sob a forma de cristais de molibdenita associados aos veios de quartzo. A alteração hidrotermal registrada é do tipo zonal concêntrica, com o núcleo potássico migrando progressivamente para uma zona distal propilítica. A alteração fílica ocorre associada a falha NW-SE. Essas fases magmáticas são álcali-cálcicas a calcialcalinas, peraluminosas a metaluminosas, com assinatura de magmatismo do tipo I cordilheiriano, alojados em ambiente tectônico de arco vulcânico a intraplaca. Exibem leve fracionamento nos ETR leves em relação aos ETR pesados ([La/Yb]N = 6-12) e discreta anomalia em Eu (Eu/Eu* = 0,2-0,9). O padrão multielementar assemelha-se ao padrão de rochas da crosta superior, com anomalias negativas em Nb-P-Ti e anomalias positivas em Rb-Sm-Tb. As razões 147Sm/144Nd das fases magmáticas indicam valor entre 0,0985 e 0,1115. As razões 143Nd/144Nd estão entre 0,512665 e 0,512738, valores que geram eNd (0) entre 0,52-1,95 e eNd (T) 0,65-2,12, indicando fonte mantélica com algum grau de contaminação crustal. Os valores de TDM (Ga) variam de 0,47-0,53. As razões 87Sr/86Sr estão entre 0,70475- 0,70627, indicando que a fonte dos magmas é o manto litosférico depletado. Dados 40Ar- 39Ar sobre biotitas hidrotermais indicam idades entre 11-14 Ma. O sistema de falhas strike-slip N-S foi o mecanismo responsável pela ascensão do magma de composição granodiorítica, o qual era enriquecido em voláteis. Durante o Mioceno, as fases finais de resfriamento, cristalização e liberação dos voláteis foram responsáveis pela formação das zonas de alteração hidrotermal e pela mineralização, que é associada ao topo dos pórfiros, além de se estenderem para a encaixante e brechas, as quais foram formadas pelo alívio de tensão e pela liberação violenta dos voláteis.The Pancho Árias Cu-Mo deposit, located in the eastern cordillera of the argentine Central Andes, is the oldest member of the Las Burras-Almagro-El Toro magmatic complex that constitute one of the main Tertiary igneous bodies located in the Calama-Olacapato-El Toro lineament. The area hosts four magmatic intrusive members in a Neoproterozoic metasedimentary basement. These members are two porphyritic andesites, one quartz-monzodioritic stock and a rhyodacitic to trachy-andesitic dike and sill system. Breccia bodies occur related to the porphyry members, and to the stock. The deposit location, as well as the textural and compositional variations, allowed us to individualize six breccia bodies, which vary from polymitic to monomitic types, and matrix suported to fragment suported. In general, the B.n breccias host the part of the Cu mineralization, in which it is formed of chalcopyrite crystals, that occasionally exhibit alteration to covellite. However, the mineralization also extends to the country rocks trapped in venules and stockwork structures. In this situation the Mo mineralization predominate and occurs as molybdenite crystals associated to quartz veins. The registered hydrothermal alteration is of the concentric zonal type, with the potassic core gradually moving to a propylitic distal zone. The phyllic alteration occurs associated to the NW-SE fault. The magmatic phases are alkali-calcic to calc-alkaline and are peraluminous to metaluminous, and the magmatism were classified as cordillerian I-type, formed in a volcanic arc to an intraplate tectonic context. They exhibit a slighly LREE fractionation in relation to HREE ([La/Yb]N = 6-12) and discreet Eu anomalies (Eu/Eu* = 0.2-0.9). The multielementar patern is similar to upper crust rocks, with Nb-P-Ti negative anomalies and Rb-Sm-Tb positive anomalies. The 147Sm/144Nd ratios of the magmatic phases indicate values of 0.0985-0.1115. The 143Nd/144Nd ratios vary between 0.512665-0.512738, values that generate eNd (0) between 0.52-1.95 and eNd (T) of 0.65- 2.12, indicating a mantle source with some degree of crustal contamination. The TDM (Ga) values vary between 0.47-0.53. The 87Sr/86Sr ratios ranging between 0,70475-0,70627, that indicated depleted lithospheric mantle source from magmas. 40Ar- 39Ar data of hydrothermal biotite indicate ages of 11-14 Ma. The data show that the strike-slip fault system is the responsible mechanism by the rise of granodiorite volatile-rich magma. During the Miocene, the final phases of cooling, crystalization, and release of volatiles processes generated the zoned hydrothermal alteration and the Cu-Mo mineralization, it is associated to the apix part of porphyry bodies, also extending to the country rocks and breccia bodies, which are were formed by stress relief and violent release of volatiles

Evaluation of Courses/Instructors: Book Cost Information and Commitment

The present study was designed to investigate the relationship between level of commitment to a college course, and information pertaining to the cost of book(s) for the course, and how such variables would interact to affect the subsequent evaluation of the course/instructor. It was expected that a state of cognitive dissonance would be present between the high commitment-higher than average cost group and the low commitment-higher than average cost group, which would manifest itself by less favorable evaluations of the course/instructor by the low commitment-higher than average group, than in the other five experimental groups. Results partially supported the prediction. It was also found that a difference existed between the high commitment-lower than average cost group and the low commitment-lower than average cost group. Such a state of cognitive dissonance was apparently reduced by less favorable evaluations of the course/instructor by the high commitment-lower than average cost group, than by the low commitment-lower than average cost group. The results were discussed in terms of cognitive dissonance theory and suggestions were made as to how and why subjects reduced any dissonance aroused. Suggestions for future research were provided

Religious and Educational Contributions of German-Russians To The Development of Rush and Ellis Counties, Kansas

Due to the unawareness of these contributions by the general public and the lack of historical facts in the Fort Hays Kansas State College library concerning these German-Russian colonies, the writer selected this thesis problem: Religious and Educational Contributions of German- Russians to the Development of Rush and Ellis Counties, Kansas. In developing the thesis the following plan obtains: (a) a statement of facts concerning the German-Russian emigration to the State of Kansas. (b) the development of the seven original colonies: Liebenthal, Catherine, Victoria, Munjor, Pfeifer, Schoenchen, and Hays. (c) the contribution of each colony to the field of religion and education. (d) the summary of each colony\u27s contributions and conclusions drawn therefrom

Calculation of three-dimensional (3-D) internal flow by means of the velocity-vorticity formulation on a staggered grid

A method has been developed to accurately compute the viscous flow in three-dimensional (3-D) enclosures. This method is the 3-D extension of a two-dimensional (2-D) method developed for the calculation of flow over airfoils. The 2-D method has been tested extensively and has been shown to accurately reproduce experimental results. As in the 2-D method, the 3-D method provides for the non-iterative solution of the incompressible Navier-Stokes equations by means of a fully coupled implicit technique. The solution is calculated on a body fitted computational mesh incorporating a staggered grid methodology. In the staggered grid method, the three components of vorticity are defined at the centers of the computational cell sides, while the velocity components are defined as normal vectors at the centers of the computational cell faces. The staggered grid orientation provides for the accurate definition of the vorticity components at the vorticity locations, the divergence of vorticity at the mesh cell nodes and the conservation of mass at the mesh cell centers. The solution is obtained by utilizing a fractional step solution technique in the three coordinate directions. The boundary conditions for the vorticity and velocity are calculated implicitly as part of the solution. The method provides for the non-iterative solution of the flow field and satisfies the conservation of mass and divergence of vorticity to machine zero at each time step. To test the method, the calculation of simple driven cavity flows have been computed. The driven cavity flow is defined as the flow in an enclosure driven by a moving upper plate at the top of the enclosure. To demonstrate the ability of the method to predict the flow in arbitrary cavities, results will he shown for both cubic and curved cavities

Computational methods for non-planar vortex wake flow fields with applications to conventional and rotating wings

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1982.Microfiche copy available in Archives and Barker.Includes bibliographical references.by Paul Michael Stremel.M.S