Computational methods for vortex dominated compressible flows

The principal objectives were to: understand the mechanisms by which Euler equation computations model leading edge vortex flows; understand the vortical and shock wave structures that may exist for different wing shapes, angles of incidence, and Mach numbers; and compare calculations with experiments in order to ascertain the limitations and advantages of Euler equation models. The initial approach utilized the cell centered finite volume Jameson scheme. The final calculation utilized a cell vertex finite volume method on an unstructured grid. Both methods used Runge-Kutta four stage schemes for integrating the equations. The principal findings are briefly summarized

LAI Lean Academy ® Lean Engineering Seminar V1.0

Lean Engineering Seminar presentatio

An embedded mesh procedure for leading-edge vortex flows

A cell-vertex scheme is outlined for solving the flow about a delta wing with M (sub infinity) is greater than 1. Embedded regions of mesh refinement allow solutions to be obtained which have much higher resolution than those achieved to date. Effects of mesh refinement and artificial viscosity on the solutions are studied, to determine at what point leading-edge vortex solutions are grid-converged. A macroscale and a microscale for the size of the vortex are defined, and it is shown that the macroscale (which includes the wing surface properties) is converged on a moderately refined grid, while the microscale is very sensitive to grid spacing. The level of numerical diffusion in the core of the vortex is found to be substantial. Comparisons with the experiment are made for two cases which have transonic cross-flow velocities

Program Future Directions

Lean Aircraft Initiative Plenary Workshop presentatio

Faculty Recital: David Earll, tuba: Music of Heroes & Monsters

TesisEl presente proyecto de investigación tuvo como objetivo principal determinar las características del financiamiento y la rentabilidad de las micro y pequeñas empresas del sector Ferreterías en la ciudad de Huaraz, periodo 2017, el tipo de investigación aplicado fue de enfoque cuantitativo y con un nivel de investigación descriptivo simple no experimental – transversal; la población estuvo comprendida por 39 representantes legales, la técnica utilizada fue la encuesta y el instrumento de medición fue el cuestionario estructurado, obteniendo los resultados siguientes: el 100 % de los encuestados tenían entre 26-65 años de edad, el 31% de los encuestados tienen estudio superior mientras que un 28% tienen estudios secundarios culminados, en las características del financiamiento; el 79% financian su actividad con fondos terceros, el 54% solicitó alguna vez su crédito en alguna entidad bancaria, el 56% afirmaron el tiempo que se le otorgó el préstamo solicitado es de largo plazo, 28% precisa en que fue invertido en capital de trabajo, en las principales características de la rentabilidad; el 74% cree que el financiamiento otorgado mejoró la rentabilidad de su empresa, el 67% cree mejoró la rentabilidad de su empresa, el 38% refieren que lograron incrementar los activos de su empresa, el 45% menciona que sus activos no se incrementaron en el año 2017. En Conclusión se han determinado las características del financiamiento y la rentabilidad del sector comercio, rubro Ferreterías en la ciudad de Huaraz. Periodo 2017 con los datos presentados en los resultados

Workshop Wrap-up

Lean Aerospace Initiative Plenary Workshop presentatio

A Framework for Achieving Lifecycle Value in Aerospace Product Development

Creation of lifecycle value - a balance of performance with cost and other attributes - represents a challenge for the development of aerospace products in the twenty-first century. This paper examines the concept of lifecycle value that stems from existing approaches of value management and analysis, lifecycle costing, and systems engineering. To ascertain common characteristics of lifecycle value creation, case studies were done for four aircraft programs: F/A- 18E/F, JAS 39 Gripen, F-16C/D, and B-777. A lifecycle value creation framework is introduced, comprised of three phases: value identification, value proposition, value delivery. Based upon observed practices in the four case studies, six value creation attributes were identified. Capability maturity models for the six attributes and three value creation phases are presented. The resulting framework represents a starting point for programs seeking to create lifecycle value for aerospace products

Navier-Stokes and Euler solutions for lee-side flows over supersonic delta wings. A correlation with experiment

An Euler flow solver and a thin layer Navier-Stokes flow solver were used to numerically simulate the supersonic leeside flow fields over delta wings which were observed experimentally. Three delta wings with 75, 67.5, and 60 deg leading edge sweeps were computed over an angle-of-attack range of 4 to 20 deg at a Mach number 2.8. The Euler code and Navier-Stokes code predict equally well the primary flow structure where the flow is expected to be separated or attached at the leading edge based on the Stanbrook-Squire boundary. The Navier-Stokes code is capable of predicting both the primary and the secondary flow features for the parameter range investigated. For those flow conditions where the Euler code did not predict the correct type of primary flow structure, the Navier-Stokes code illustrated that the flow structure is sensitive to boundary layer model. In general, the laminar Navier-Stokes solutions agreed better with the experimental data, especially for the lower sweep delta wings. The computational results and a detailed re-examination of the experimental data resulted in a refinement of the flow classifications. This refinement in the flow classification results in the separation bubble with the shock flow type as the intermediate flow pattern between separated and attached flows

Virtual Assessment of Lean User Experience (VALUE)

A guide to assessing your level of lean enterprise knowledg