679 research outputs found

    Heat Transfer

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    Over the past few decades there has been a prolific increase in research and development in area of heat transfer, heat exchangers and their associated technologies. This book is a collection of current research in the above mentioned areas and describes modelling, numerical methods, simulation and information technology with modern ideas and methods to analyse and enhance heat transfer for single and multiphase systems. The topics considered include various basic concepts of heat transfer, the fundamental modes of heat transfer (namely conduction, convection and radiation), thermophysical properties, computational methodologies, control, stabilization and optimization problems, condensation, boiling and freezing, with many real-world problems and important modern applications. The book is divided in four sections : "Inverse, Stabilization and Optimization Problems", "Numerical Methods and Calculations", "Heat Transfer in Mini/Micro Systems", "Energy Transfer and Solid Materials", and each section discusses various issues, methods and applications in accordance with the subjects. The combination of fundamental approach with many important practical applications of current interest will make this book of interest to researchers, scientists, engineers and graduate students in many disciplines, who make use of mathematical modelling, inverse problems, implementation of recently developed numerical methods in this multidisciplinary field as well as to experimental and theoretical researchers in the field of heat and mass transfer

    Advanced Topics in Mass Transfer

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    This book introduces a number of selected advanced topics in mass transfer phenomenon and covers its theoretical, numerical, modeling and experimental aspects. The 26 chapters of this book are divided into five parts. The first is devoted to the study of some problems of mass transfer in microchannels, turbulence, waves and plasma, while chapters regarding mass transfer with hydro-, magnetohydro- and electro- dynamics are collected in the second part. The third part deals with mass transfer in food, such as rice, cheese, fruits and vegetables, and the fourth focuses on mass transfer in some large-scale applications such as geomorphologic studies. The last part introduces several issues of combined heat and mass transfer phenomena. The book can be considered as a rich reference for researchers and engineers working in the field of mass transfer and its related topics

    A Study of Heat Transfer in Rotary Desorbers Used to Remediate Contaminated Soils.

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    A comprehensive heat transfer model is developed which describes heat transfer phenomena in rotary desorbers. This model predicts the temperatures of the solids bed and gases in the desorber and the rate of water evaporation from the solids. Emphasis is placed on describing the heat transfer process between the rotating wall of a desorber and the adjacent bed of solids. A heat-balance integral method is used to model heat conduction from the wall to adjacent wet bed particles. This solution includes the effects of water evaporation near the wall and a thermal contact resistance between the wall and the first layer of particles. The model allows for water evaporation before the bulk bed temperature reaches the saturation temperature of the water. Radiative and convective heat transfer to the solids are coupled with the wall-to-bed heat transfer rate to find the total heat transfer rate to the solids. Energy balances are performed on an axial zone of the desorber and are used to find the resulting change in solids and gas temperatures across the zone, thereby predicting axial temperature profiles. Experiments are performed on a batch-type, pilot-scale desorber. A bed temperature probe is used to determine the transient temperature of the bed at several radial and axial locations. In these experiments, the particle size, the rotation rate, and the initial moisture content of the solids are varied. It is found that particles heated by the rotating wall are not completely mixed with the remainder of the bed, reducing wall-to-bed heat transfer. Evaporation rates are inferred from measured velocities at the exit of the desorber. Mass balances are performed on the water, with good results. A significant amount of water is found to evaporate before the bulk bed temperature reaches the water saturation temperature. The measured bed temperatures and evaporation rates compare favorably to predictions of the model. The important features of the experimental data, including the bulk bed temperature profiles and water evaporation before the bed temperature reaches the water saturation temperature, are predicted

    Solid rocket motor internal insulation

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    Internal insulation in a solid rocket motor is defined as a layer of heat barrier material placed between the internal surface of the case propellant. The primary purpose is to prevent the case from reaching temperatures that endanger its structural integrity. Secondary functions of the insulation are listed and guidelines for avoiding critical problems in the development of internal insulation for rocket motors are presented

    The Fifth Annual Thermal and Fluids Analysis Workshop

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    The Fifth Annual Thermal and Fluids Analysis Workshop was held at the Ohio Aerospace Institute, Brook Park, Ohio, cosponsored by NASA Lewis Research Center and the Ohio Aerospace Institute, 16-20 Aug. 1993. The workshop consisted of classes, vendor demonstrations, and paper sessions. The classes and vendor demonstrations provided participants with the information on widely used tools for thermal and fluid analysis. The paper sessions provided a forum for the exchange of information and ideas among thermal and fluids analysts. Paper topics included advances and uses of established thermal and fluids computer codes (such as SINDA and TRASYS) as well as unique modeling techniques and applications

    Mass Transfer in Multiphase Systems and its Applications

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    This book covers a number of developing topics in mass transfer processes in multiphase systems for a variety of applications. The book effectively blends theoretical, numerical, modeling and experimental aspects of mass transfer in multiphase systems that are usually encountered in many research areas such as chemical, reactor, environmental and petroleum engineering. From biological and chemical reactors to paper and wood industry and all the way to thin film, the 31 chapters of this book serve as an important reference for any researcher or engineer working in the field of mass transfer and related topics

    Research reports: 1990 NASA/ASEE Summer Faculty Fellowship Program

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    Reports on the research projects performed under the NASA/ASEE Summer Faculty Fellowship Program are presented. The program was conducted by The University of Alabama and MSFC during the period from June 4, 1990 through August 10, 1990. Some of the topics covered include: (1) Space Shuttles; (2) Space Station Freedom; (3) information systems; (4) materials and processes; (4) Space Shuttle main engine; (5) aerospace sciences; (6) mathematical models; (7) mission operations; (8) systems analysis and integration; (9) systems control; (10) structures and dynamics; (11) aerospace safety; and (12) remote sensin

    Aeronautical Engineering, A Continuing Bibliography With Indexes

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    This bibliography lists 693 reports, articles and other documents introduced into the NASA scientific and technical information system in September 1984

    Assessment of tbe Performance of Ablative Insulators Under Realistic Solid Rocket Motor Operating Conditions (a Doctoral Dissertation)

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    Ablative insulators are used in the interior surfaces of solid rocket motors to prevent the mechanical structure of the rocket from failing due to intense heating by the high-temperature solid-propellant combustion products. The complexity of the ablation process underscores the need for ablative material response data procured from a realistic solid rocket motor environment, where all of the potential contributions to material degradation are present and in their appropriate proportions. For this purpose, the present study examines ablative material behavior in a laboratory-scale solid rocket motor. The test apparatus includes a planar, two-dimensional flow channel in which flat ablative material samples are installed downstream of an aluminized solid propellant grain and imaged via real-time X-ray radiography. In this way, the in-situ transient thermal response of an ablator to all of the thermal, chemical, and mechanical erosion mechanisms present in a solid rocket environment can be observed and recorded. The ablative material is instrumented with multiple micro-thermocouples, so that in-depth temperature histories are known. Both total heat flux and thermal radiation flux gauges have been designed, fabricated, and tested to characterize the thermal environment to which the ablative material samples are exposed. These tests not only allow different ablative materials to be compared in a realistic solid rocket motor environment but also improve the understanding of the mechanisms that influence the erosion behavior of a given ablative material

    Proceedings of the 2018 Canadian Society for Mechanical Engineering (CSME) International Congress

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    Published proceedings of the 2018 Canadian Society for Mechanical Engineering (CSME) International Congress, hosted by York University, 27-30 May 2018
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