Wesley Harris

Massachusetts Institute of Technology (MIT), Aeronautics and Astronautics, Faculty Member

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Andrej Dujella

University of Zagreb

Hemin Koyi

Uppsala University

Jana Javornik

University of East London

Graham Martin

University of Leicester

Gwen Robbins Schug

University of North Carolina at Greensboro

Gabriel Gutierrez-Alonso

University of Salamanca

John Sutton

Macquarie University

Eros Carvalho

Universidade Federal do Rio Grande do Sul

Kevin Arbuckle

Swansea University

Jesper Hoffmeyer

University of Copenhagen

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Papers by Wesley Harris

A Vehicle Design and Optimization Model for On-Demand Aviation

2018 AIAA/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference, Jan 7, 2018

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Anechoic wind tunnel study of turbulence effects on wind turbine broadband noise

Unclassified 15. NUMBER OF PAGES 243 16. PRICE CODE All 20. LIMITATION OF AB_ i HACT Standard For... more

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Wind tunnel investigations of model rotor noise at low tip speeds

This paper summarizes the experimental and related analytical results on model rotor rotational a... more This paper summarizes the experimental and related analytical results on model rotor rotational and broadband noise obtained at M.I.T. since 1975. The objectives of this research program have been to define the various noise sources, to determine the effects of helicopter performance parameters on the noise generated by a model main rotor , and to derive appropriate scaling laws for the various types of main rotor noise. A description of the M.I.T. anechoic wind tunnel and rotor facility and some of the findings of this research group have been reported previously. The parameters under study were the variation of helicopter performance parameters such as number of blades, blade pitch (thrust), and advance ratio. In addition, the research program has consisted of an examination of the effects of intensity and size scales of injested turbulence on the intensity and spectra of broadband noise.

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Research on unsteady, nonlinear transonic flow

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The development of experimental techniques for the study of helicopter rotor noise

P r~f e s s o r Shei I d f. n'ii!ndll P r o f e s s~r Uesiey I.. &:mi s Ying-Chieh Albert l e e a... more P r~f e s s o r Shei I d f. n'ii!ndll P r o f e s s~r Uesiey I.. &:mi s Ying-Chieh Albert l e e and H2rman : I. 3rees Massachusetts I n s t i t u t e o f Technology Department of Aeronautics and Astronautics F l u i d Dynamics Research L a b o r a b r y Cambridge, Massachusetts 021 39 Final Report NAS2-7684 June 1973 t o November 1974 MRDLINASA Ames M o f f e t t F i e l d , C a l i f o r n i a (13ASF.-C3-1376dU) THE CZVSLaF'lEYT O? E75-23611 FX?Z?IRSNTAL T3CRYI.zdSS YO!: T H 3 STUDY O f dELIC3FTZP EOTOF NJISE T i n a 1 iieport, Jun.

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2-D Model for Normal and Sickle Cell Blood Microcirculation

Bulletin of the American Physical Society, Nov 20, 2011

Submitted for the DFD11 Meeting of The American Physical Society 2-D Model for Normal and Sickle ... more Submitted for the DFD11 Meeting of The American Physical Society 2-D Model for Normal and Sickle Cell Blood Microcirculation YONATAN TEKLEAB, WESLEY HARRIS, Massachusetts Institute of Technology-Sickle cell disease (SCD) is a genetic disorder that alters the red blood cell (RBC) structure and function such that hemoglobin (Hb) cannot effectively bind and release oxygen. Previous computational models have been designed to study the microcirculation for insight into blood disorders such as SCD. Our novel 2-D computational model represents a fast, time efficient method developed to analyze flow dynamics, O 2 diffusion, and cell deformation in the microcirculation. The model uses a finite difference, Crank-Nicholson scheme to compute the flow and O 2 concentration, and the level set computational method to advect the RBC membrane on a staggered grid. Several sets of initial and boundary conditions were tested. Simulation data indicate a few parameters to be significant in the perturbation of the blood flow and O 2 concentration profiles. Specifically, the Hill coefficient, arterial O 2 partial pressure, O 2 partial pressure at 50% Hb saturation, and cell membrane stiffness are significant factors. Results were found to be consistent with those of Le Floch [2010] and Secomb [2006].

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Application of quasi-linearization techniques to the analysis of aerodynamic-noise fields

The method of parametric differentiation has been applied as a means of obtaining solutions which... more The method of parametric differentiation has been applied as a means of obtaining solutions which describe aerodynamically generated sound fields and which are valid over an increased range of a specific parameter. The method is shown to be useful for a particular class of aerodynamic sound fields. Details of applying the method of parametric differentiation to the problem of caleu I at ing.the sound field of two rectilinear vortices rotating about an axis between them in a compressible medium are discussed. Pressure distribution in the far field are obtained. The results appear to be reasonable physically and mathematically self-consistent. The method of parametric differentiation has also been applied by the author to the problem of calculating the aerodynamic sound generated by a rotating cyIinder in a viscous, compressible medium. The formulation of this problem in parametric space is given and a procedure for obtaining a solution is outlined.

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Opportunities and Challenges in Corrosion Education: Review of a National Research Council Assessment

Interface magazine, 2012

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Chaos In The Onset Of Sickle Cell Crises

WIT transactions on engineering sciences, 2004

A novel unsteady Eulerian-based model [Apori-Harris model] that includes the oxygen concentration... more A novel unsteady Eulerian-based model [Apori-Harris model] that includes the oxygen concentration, red blood cell average velocity, cell stiffness, and plasma viscosity as dependent state variables has been developed and is used to investigate the chaotic onset of sickle cell blood flow crises in capillaries. In canonical form, the Apori-Harris model is a set of coupled, non-linear equations in which the velocity-viscosity and viscosity-cell stiffness relationships dominate the physics of the model. The equation set is investigated to determine its chaotic properties with respect to control parameters representing the specific rheology of the sickle cell erythrocytes. Determining the sensitivity of the Apori-Harris model to changes in each parameter defines the process for identifying the dominant control parameters. A mathematically rigorous definition and a clinically acceptable definition of sickle cell crises onset in capillaries have been derived and are based on the eigenvalue...

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Welcome and Introduction of New Members

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Policy Economic Incentives: C-17 Case Study

What are the primary strategies, barriers, enablers What are the primary strategies, barriers, en... more

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Sustainment Operations Team Final Report

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Technologies, Inc

engineers and scientists of their generation, proposed the 14 challenges outlined in this booklet... more engineers and scientists of their generation, proposed the 14 challenges outlined in this booklet. The panel, which was convened by the U.S. National Academy of Engineering (NAE) at the request of the U.S. National Science Foundation, did not rank the challenges selected, nor did it endorse particular approaches to meeting them. Rather than attempt to include every important goal for engineering, the panel chose opportunities that were both achievable and sustainable to help people and the planet thrive. The panel’s conclusions were reviewed by more than 50 subject-matter experts. In addition, the effort received worldwide input from prominent engineers and scientists, as well as from the general public. The NAE is offering an opportunity to comment on the challenges via the project’s interactive Web site at www.engineeringchallenges.org.

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A robust computational approach to Lees–Dorodnitsyn laminar hypersonic boundary layers with temperature-dependent properties

Physics of Fluids

The Lees–Dorodnitsyn (L–D) boundary layer equations for two-dimensional, non-reactive, laminar, h... more The Lees–Dorodnitsyn (L–D) boundary layer equations for two-dimensional, non-reactive, laminar, hypersonic, boundary layer flows, and an assumption of an isentropic external flow are examined. They are applied to various geometries for which the Thin Shear Layer assumptions are valid. This study expands on previous work to develop a novel and robust methodology for computing high-temperature hypersonic flows using a uniform and compact computational stencil implemented through a computational tool, the Bulk-property Boundary Layer (BuBL) solver. In particular, we explore the impact of treating high-temperature effects present in hypersonic flows, namely, treating air as a thermally perfect gas with temperature-variable properties. The ability to solve these flows computationally using second-order finite difference methods is evaluated as are various models for viscosity, Prandtl number, and specific heat. The methodology for solving the external flow properties in the transformed L...

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Deterministic Aperiodic Sickle Cell Blood Flows

by Louis Atsaves and Wesley Harris

A Magnetorheological Hemostatic Agent

Bulletin of the American Physical Society, 2019

Assessing Chaos in Sickle Cell Anemia Crises

Bulletin of the American Physical Society, 2006

Recent developments in sickle cell research and blood flow modeling allow for new interpretations... more Recent developments in sickle cell research and blood flow modeling allow for new interpretations of the sickle cell crises. With an appropriate set of theoretical and empirical equations describing the dynamics of the red cells in their environment, and the response of the capillaries to major changes in the rheology, a complete mathematical system has been derived. This system of equations is believed to be of major importance to provide new and significant insight into the causes of the disease and related crises. With simulations, it has been proven that the system transition from a periodic solution to a chaotic one, which illustrates the onset of crises from a regular blood flow synchronized with the heart beat. Moreover, the analysis of the effects of various physiological parameters exposes the potential to control chaotic solutions, which, in turn, could lead to the creation of new and more effective treatments for sickle cell anemia. .

Space Technology and Africa's Development: The Strategic Role of Small Satellites

SSRN Electronic Journal, 2017

Visit the HKS Faculty Research Working Paper Series at: https://www.hks.harvard.edu/research-insi... more Visit the HKS Faculty Research Working Paper Series at: https://www.hks.harvard.edu/research-insights/publications?f%5B0%5D=publication_types%3A121 The views expressed in the HKS Faculty Research Working Paper Series are those of the author(s) and do not necessarily reflect those of the John F. Kennedy School of Government or of Harvard University. Faculty Research Working Papers have not undergone formal review and approval. Such papers are included in this series to elicit feedback and to encourage debate on important public policy challenges. Copyright belongs to the author(s). Papers may be downloaded for personal use only.

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Chaos in an Eulerian Based Model of Sickle Cell Blood Flow

A novel Eulerian model describing the manifestation of sickle cell blood flow in the capillaries ... more A novel Eulerian model describing the manifestation of sickle cell blood flow in the capillaries has been formulated to study the apparently chaotic onset of sickle cell crises. This Eulerian model was based on extending previous models of sickle cell blood flow which were limited due to their Lagrangian formulation. Oxygen concentration, red blood cell velocity, cell stiffness, and plasma viscosity were modeled as system state variables. The governing equations of the system were expressed in canonical form. The non-linear coupling of velocity-viscosity and viscosity- stiffness proved to be the origin of chaos in the system. The system was solved with respect to a control parameter representing the unique rheology of the sickle cell erythrocytes. Results of chaos tests proved positive for various ranges of the control parameter. The results included con-tinuous patterns found in the Poincare section, spectral broadening of the Fourier power spectrum, and positive Lyapunov exponent ...