Download or read book Heat Transfer from Swirling Impinging Jets written by M. Mahmood and published by . This book was released on 1980 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis is concerned with the determination of thelocal and average mass/heat transfer--from swirling jetsimpinging orthogonally onto flat surfaces. ApplicatioCn>of swirl alters the flow field of the jet considerablyand eventually the maximum velocity in the jet is displacedfrom the axis resulting in a typical double-peak profile. Further increase of swirl, can even result in arecirculation in the inner core of the flow. The turbulencecharacteristics of the jet are also affected. itis expected that these changes will, in addition, modifythe heat transfer behaviour. Consequently, a study of both single free jets and asquare array (of 3x 3) of jets was undertaken. Therange of swirls examined in this study was from zerothrough to weak and then medium swirl, i. e. the swirlnumber S was varied from 0 to 0.48. The other parametersvaried in the experiments were the nozzle-to-targetspacing z/D from 2 to 12, the nozzle pitches x/D (forarrays of jets) which were 3.2,4.8 and 6.4, and the jGtReynolds number. In the single frce jet tests, two flowrates corresponding to ReD-":2 32pOOO and 60,000 were studiedwhilst, for the multiple jets, the measurementswere confined. to the lower of these Reynolds numbers.(ReD is based on the mean exit velocity in the non-swirlingcase and the diameter of the nozzle.)Limited velocity and turbulence measurements were alsoundertaken on the single jet to characterise the flowand also to compare the behaviour of the present jetswith those in previous studies. The flows were similarto those observed previously for swirling jets so thatthe heat transfer results should be generally applicable. A thin-film naphthalene sublimation technique was usedto measure mass transfers over the target surface. Theheat transfer coefficients were then derived using theChilton-Colburn analogy. A rig was developed to spraya uniform coating of naphthalene on the target surface. This thin-film technique was found to provide repeatableresults and the validity of the experiments was further assessed by comparing the results with previouslypublished data for the no swirl case. These were inreasonable agreement. For the single free jets, the application of swirl wasfound to continuously reduce the heat transfers. Theheat transfers, however, became more uniform. An empiricalcorrelation has also been suggested for the averageNusselt number associated with these single swirling jets and is valid for S= 0.12-to 0.48. In some circumstancesin the multiple jet tests (e. g. at close nozzle-to-target spacings) the average heat transfers increasedto a maximum of IS =0.24 (approximately). Further increasesin the degree of swirl brought about a subsequentreduction in average heat transfer coefficients untileventually the performance of the swirling jets was poorerthan that of the non-swirling flows. This discrepancyin behaviour can be explained in terms of changes in thelocal heat transfer distributions.
Download or read book Flow Field and Heat Transfer in Swirling Impinging Jets written by Andrea Ianiro and published by . This book was released on 2011 with total page 118 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Heat Transfer Characteristics of Swirling Impinging Jets written by Karl J. Brown and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Heat Transfer from Swirling Impinging Jets written by and published by . This book was released on 1904 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis is concerned with the determination of the local and average mass/heat transfer--from swirling jets impinging orthogonally onto flat surfaces. ApplicatioCn> of swirl alters the flow field of the' jet considerably and eventually the maximum velocity in the jet is displaced from the axis resulting in a typical 'double-peak' profile. Further increase of swirl, can even result in a recirculation in the inner core of the flow. The turbulence characteristics of the jet are also affected. it is expected that these changes will, in addition, modify the heat transfer behaviour. Consequently, a study of both single free jets and a square array (of 3x 3) of jets was undertaken. The range of swirls examined in this study was from zero through to weak and then medium swirl, i. e. the swirl number S was varied from 0 to 0.48. The other parameters varied in the experiments were the nozzle-to-target spacing z/D from 2 to 12, the nozzle pitches x/D (for arrays of jets) which were 3.2,4.8 and 6.4, and the jGt Reynolds number. In the single frce jet tests, two flow rates corresponding to ReD-":2 32pOOO and 60,000 were studied whilst, for the 'multiple' jets, the measurements were confined. to the lower of these Reynolds numbers. (ReD is based on the mean exit velocity in the non-swirling case and the diameter of the nozzle.) Limited velocity and turbulence measurements were also undertaken on the single jet to characterise the flow and also to compare the behaviour of the present jets with those in previous studies. The flows were similar to those observed previously for swirling jets so that the heat transfer results should be generally applicable. A 'thin-film' naphthalene sublimation technique was used to measure mass transfers over the target surface. The heat transfer coefficients were then derived using the Chilton-Colburn analogy. A rig was developed to spray a uniform coating of naphthalene on the target surface. This 'thin-film' technique was found to provide re.
Download or read book Heat Transfer and Flow Visualization of Conventional and Swirling Impinging Jets written by Lianmin Huang and published by . This book was released on 1996 with total page 522 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Prediction of Flow and Heat Transfer Under a Laminar Swirling Impinging Jet written by Bing Huang and published by . This book was released on 1977 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Proceedings Of The International Heat Transfer Conference written by Lee and published by CRC Press. This book was released on 1998-11-01 with total page 696 pages. Available in PDF, EPUB and Kindle. Book excerpt: This year's set of papers includes 23 Keynote Papers and 537 refereed General Papers, in seven volumes. Experts from around the world have combined to address the leading edge of research and practical innovations in convection, combustion, heat exchangers, two-phase flow, and much more. Whether one is involved in mechanical, chemical, nuclear, or energy engineering the quantity, international scope, and high quality of the contents make access to these volumes essential.
Download or read book Study of flow and heat transfer characteristics in a swirling impinging jet written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: O presente trabalho é um estudo experimental das características de um escoamento de ar em forma de jato espiralado, incidindo ortogonalmente sobre uma placa. Os objetivos do estudo são: avaliar a influência da presença de uma componente circunferencial de velocidade na distribuição dos coeficientes locais de troca de calor, obter campos de velocidade instantâneos no plano axissimétrico assim como informações sobre as características da turbulência no escoamento. Durante os experimentos se investigou a influência da distância jato/placa e da intensidade do escoamento espiralado (número de Swirl). Como etapa preliminar, foi conduzido um experimento de jato livre, para validação das técnicas de medição de velocidade utilizadas. Os resultados foram comparados com os da literartura e uma boa concordância foi obtida. A distribuição espacial dos coeficientes de troca de calor foi avaliada impondo-se um fluxo de calor constante na placa e medindo a distribuição radial de temperatura através de diversos termopares. Coeficientes locais puderam então ser estimados. Os campos de velocidades radial e axial instantâneos foram adquiridos experimentalmente através da utilização da técnica de Particle Image Velocimetry (PIV) e perfis de velocidade tangencial (média e flutuações) foram obtidos a partir da técnica Laser Doppler Velocimetry (LDV). Os resultados mostraram que os padrões de escoamento mudam significativamente quando a componente circunferencial de velocidade é introduzida. Para o valor mais alto do Número de Swirl foram verificadas fortes reversões do escoamento na região de estagnação.
Download or read book Impingement Jet Cooling in Gas Turbines written by R.S. Amano and published by WIT Press. This book was released on 2014-05-28 with total page 253 pages. Available in PDF, EPUB and Kindle. Book excerpt: Due to the requirement for enhanced cooling technologies on modern gas turbine engines, advanced research and development has had to take place in field of thermal engineering. Among the gas turbine cooling technologies, impingement jet cooling is one of the most effective in terms of cooling effectiveness, manufacturability and cost. The chapters contained in this book describe research on state-of-the-art and advanced cooling technologies that have been developed, or that are being researched, with a variety of approaches from theoretical, experimental, and CFD studies. The authors of the chapters have been selected from some of the most active researchers and scientists on the subject. This is the first to book published on the topics of gas turbines and heat transfer to focus on impingement cooling alone.
Download or read book Infrared Thermography for Thermo Fluid Dynamics written by Tommaso Astarita and published by Springer Science & Business Media. This book was released on 2012-08-04 with total page 237 pages. Available in PDF, EPUB and Kindle. Book excerpt: Infrared thermography is a measurement technique that enables to obtain non intrusive measurements of surface temperatures. One of the interesting features of this technique is its ability to measure a full two dimensional map of the surface temperature and for this reason it has been widely used as a flow visualization technique. Since the temperature measurements can be extremely accurate it is possible, by using a heat flux sensor, also to measure convective heat transfer coefficient distributions on a surface making the technique de facto quantitative. This book, starting from the basic theory of infrared thermography and heat flux sensor guides, both the experienced researcher and the young student, in the correct application of this powerful technique to various practical problems. A significant number of examples and applications are also examined in detail.
Download or read book Food Engineering Integrated Approaches written by Gustavo F. Gutiérrez-Lopez and published by Springer Science & Business Media. This book was released on 2008-02-29 with total page 475 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents a significant and up-to-date review of various integrated approaches to food engineering. Distinguished food engineers and food scientists from key institutions worldwide have contributed chapters that provide a deep analysis of their particular subjects. Emerging technologies and biotechnology are introduced, and the book discusses predictive microbiology, packing materials for foods, and biodegradable films. This book is mainly directed to academics, and to undergraduate and postgraduate students in food engineering and food science and technology, who will find a selection of topics.
Download or read book Fundamental Principles of Heat Transfer written by Stephen Whitaker and published by Elsevier. This book was released on 2013-10-22 with total page 575 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fundamental Principles of Heat Transfer introduces the fundamental concepts of heat transfer: conduction, convection, and radiation. It presents theoretical developments and example and design problems and illustrates the practical applications of fundamental principles. The chapters in this book cover various topics such as one-dimensional and transient heat conduction, energy and turbulent transport, forced convection, thermal radiation, and radiant energy exchange. There are example problems and solutions at the end of every chapter dealing with design problems. This book is a valuable introductory course in heat transfer for engineering students.
Download or read book Advances in Heat Transfer Augmentation Techniques in Single Phase Flows written by Varun Goel and published by CRC Press. This book was released on 2024-01-26 with total page 309 pages. Available in PDF, EPUB and Kindle. Book excerpt: Augmentation of heat transfer is important in energy conservation and developing sustainable energy systems. This book provides the science necessary to understand the basics of heat transfer augmentation in single-phase engineering systems. It considers theory and practice including computational and experimental procedures, evaluation techniques for performance, and new trends. Several applications of augmentation methods like surface modification, introduction of vortex flow and impinging jets, opportunities of ultrasound and magnetic fields, pulsatile flows, heat exchangers, and nanofluids are provided. Details of basic phenomena and mechanisms are highlighted. Key features: Provides the fundamental science needed to understand and further develop heat transfer augmentation for future energy systems Give examples of how ultrasound and magnetic fields, vortex flow, impinging jets, surface modification and nanofluids can augment heat transfer Considers basic issues of computational and experimental methods for analysis, design, and evaluation of efficient and sustainable heat transfer It is an ideal reference text for graduate students and academic researchers working in the fields of mechanical, aerospace, industrial, manufacturing, and chemical engineering.
Download or read book Swirl Flows written by Ashwani K. Gupta and published by Routledge. This book was released on 1984 with total page 496 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Heat Transfers from Impinging Swirling Jets written by C.J. Perry and published by . This book was released on 1975 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Numerical Heat Transfer and Fluid Flow written by D. Srinivasacharya and published by Springer. This book was released on 2018-12-13 with total page 657 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book comprises selected papers from the International Conference on Numerical Heat Transfer and Fluid Flow (NHTFF 2018), and presents the latest developments in computational methods in heat and mass transfer. It also discusses numerical methods such as finite element, finite difference, and finite volume applied to fluid flow problems. Providing a good balance between computational methods and analytical results applied to a wide variety of problems in heat transfer, transport and fluid mechanics, the book is a valuable resource for students and researchers working in the field of heat transfer and fluid dynamics.
Download or read book Heat Transfer Characteristics of Impinging Premixed Flame Jet with Induced Swirl written by Xiaoqun Huang and published by . This book was released on 2006 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt:
