Download or read book Turbulence Scales in the Passage of a Linear Turbine Cascade written by James L. Acree (CAPT, USAF.) and published by . This book was released on 1990 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Turbulence Scales in the Passage of a Linear Turbine Cascade written by James L. Acree and published by . This book was released on 1990 with total page 193 pages. Available in PDF, EPUB and Kindle. Book excerpt: Convective heat transfer in a turbine cascade is examined for turbulence effects. Turbulence in the free stream is varied by injection of air through a jet-grid device upstream of the cascade. Pressure and flow patterns on the blade surface, and flow velocity in two components, are examined to determine the effect of the jet-grid. Velocity and velocity fluctuation in two components are measured. Local turbulence scales through the cascade passage are determined, and local turbulent energy dissipation rate is determined. Results indicate injection of air through the jet-grid changes the angle of incidence, and therefore changes the surface pressures and velocities on the blade. Heat transfer comparison is thereby invalidated. Variations in jet-grid plenum pressure change the turbulence microscale at the cascade entrance, but not the integral scale. Turbulence intensity is likewise relatively unaffected. Turbulence behavior in the passage indicates that velocity fluctuation and turbulence microscale are inversely related; turbulence intensity and microscale are not inversely related. With 6% freestream turbulence intensity, turbulence in the passage center is influenced first by events near the suction surface, then by events near the pressure surface. The primary vehicle for cross-stream diffusion is increased cross-stream velocity component fluctuations.
Download or read book Turbulence Scale Effects on Heat Transfer in a Linear Turbine Cascade written by and published by . This book was released on 1989 with total page 282 pages. Available in PDF, EPUB and Kindle. Book excerpt: Heat transfer for a turbine cascade is examined for turbulence scale effects. The turbulence integral scale and microscale lengths of the free-stream flow are controlled by air-jet injection through a grid placed in the free- stream flow. Air is injected into the flow in three primary directions: co-flow, cross-flow, and counter-flow, at several injection pressures. Results are obtained for heat transfer on the blade without the jet-grid in the free-stream flow. Surface pressures on the turbine blade are examined for three injection directions. Surface heat transfer on the blade and turbulence intensity and turbulence scale results are obtained for two grid locations, three air injection orientations, and three injection orifice diameters over a range of injection pressures. Turbulence integral scale and microscale lengths are measured in two free-stream flow coordinates. Results show the integral scale length is primarily dependent on the diameter of the jet-grid tube, but may be controlled to a lesser degree by changing the orientation of the jet-grid injection to a co-flow or counter-flow direction; or by changing the secondary air-jet injection pressure. The turbulence microscale is primarily dependent on the location of the jet-grid within the flow, but, to a lesser degree, controlled by the orientation of the jet-grid injection, jet orifice diameter, and injection pressure.
Download or read book Turbulence Scale Effects on Heat Transfer in a Linear Turbine Cascade written by Lello Galassi (CAPT, USAF.) and published by . This book was released on 1989 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 488 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Download or read book Secondary Flow Measurements in a Turbine Cascade with High Inlet Turbulence written by D. G. Gregory-Smith and published by . This book was released on 1990 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Measurements of the mean and turbulent flow field have been made in a cascade of high turning turbine rotor blades. The inlet turbulence was raised to 5 percent by a grid placed upstream of the cascade, and the secondary flow region was traversed within and downstream of the blades using a five-hole probe and crossed hot wires. Flow very close to the end wall was measured using a single wire placed at several orientations. Some frequency spectra of the turbulence were also obtained. The results show that the mean flow field is not affected greatly by the high inlet turbulence. The Reynolds stresses were found to be very high, particularly in the loss core. Assessment of the contributions to production of turbulence by the Reynolds stresses shows that the normal stresses have significant effects, as do the shear stresses. The calculation of eddy viscosity from two independent shear stresses shows it to be fairly isotropic in the loss core. Within the blade passage, the flow close to the end wall is highly skewed and exhibits generally high turbulence. The frequency spectra show no significant resonant peaks, except for one at very low frequency, attributable to an acoustic resonance.
Download or read book Endwall Heat Transfer Measurements in a Transonic Turbine Cascade written by and published by . This book was released on 1996 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: Turbine blade endwall heat transfer measurements are given for a range of Reynolds and Mach numbers. Data were obtained for Reynolds numbers based on inlet conditions of 0.5 and 1.0 x 10(exp 6), for isentropic exit Mach numbers of 1.0 and 1.3, and for freestream turbulence intensities of 0.25% and 7.0%. Tests were conducted in a linear cascade at the NASA Lewis Transonic Turbine Blade Cascade Facility. The test article was a turbine rotor with 136 deg of turning and an axial chord of 12.7 cm. The large scale allowed for very detailed measurements of both flow field and surface phenomena. The intent of the work is to provide benchmark quality data for CFD code and model verification. The flow field in the cascade is highly three-dimensional as a result of thick boundary layers at the test section inlet. Endwall heat transfer data were obtained using a steady-state liquid crystal technique.
Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1989 with total page 410 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Heat Transfer Predictions for Two Turbine Nozzle Geometries at High Reynolds and Mach Numbers written by R. J. Boyle and published by . This book was released on 1995 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presented at the International Gas Turbine and Aeroengine Congress & Exposition, Houston, Texas - June 5-8, 1995.
Download or read book Gas Turbine Heat Transfer and Cooling Technology written by Je-Chin Han and published by Taylor & Francis. This book was released on 2012-11-27 with total page 865 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive reference for engineers and researchers, this second edition focuses on gas turbine heat transfer issues and their associated cooling technologies for aircraft and land-based gas turbines. It provides information on state-of-the-art cooling technologies such as advanced turbine blade film cooling and internal cooling schemes. The book also offers updated experimental methods for gas turbine heat transfer and cooling research, as well as advanced computational models for gas turbine heat transfer and cooling performance predictions. The authors provide suggestions for future research within this technology and includes 800 illustrations to help clarify concepts and instruction.
Download or read book Intrapassage Flow Measurements in a Large scale Turbine Cascade written by Patrick Kavanagh and published by . This book was released on 1987 with total page 88 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 Masters Theses in the Pure and Applied Sciences written by Wade H. Shafer and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 426 pages. Available in PDF, EPUB and Kindle. Book excerpt: Masters Theses in the Pure and Applied Sciences was first conceived, published, and disseminated by the Center for Information and Numerical Data Analysis and Synthesis (CINDAS)* at Purdue University in 1957, starting its coverage of theses with the academic year 1955. Beginning with Volume 13, the printing and dis semination phases of the activity were transferred to University Microfilms/Xerox of Ann Arbor, Michigan, with the thought that such an arrangement would be more beneficial to the academic and general scientific and technical community. After five years of this joint undertaking we had concluded that it was in the interest of all concerned if the printing and distribution of the volumes were handled by an international publishing house to assure improved service and broader dissemination. Hence, starting with Volume 18, Masters Theses in the Pure and Applied Sciences has been disseminated on a worldwide basis by Plenum Publishing Corporation of New York, and in the same year the coverage was broadened to include Canadian universities. All back issues can also be ordered from Plenum. We have reported in Volume 38 (thesis year 1993) a total of 13,787 thesis titles from 22 Canadian and 164 United States universities. We are sure that this broader base for these titles reported will greatly enhance the value of this impor tant annual reference work. While Volume 38 reports theses submitted in 1993, on occasion, certain uni versities do report theses submitted in previous years but not reported at the time.
Download or read book AIAA 90 2251 AIAA 90 2299 written by and published by . This book was released on 1990 with total page 378 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fundamental Problematic Issues in Turbulence written by Albert Gyr and published by Birkhäuser. This book was released on 2012-12-06 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt: A collection of contributions on a variety of mathematical, physical and engineering subjects related to turbulence. Topics include mathematical issues, control and related problems, observational aspects, two- and quasi-two-dimensional flows, basic aspects of turbulence modeling, statistical issues and passive scalars.
Download or read book A Frequency Domain Analysis of Surface Heat Transfer Free Stream Turbulence Interactions in a Transonic Turbine Cascade written by David G. Holmberg and published by . This book was released on 1996 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The relationship of time resolved surface heat flux to the turbulent free stream flow over a turbine blade is investigated. Measurements are made in a transonic linear cascade with a modern high pressure turbine blade profile. Time resolved direct heat transfer measurements are made with Heat Flux Microsensor (HFM) inserts along the pressure side, and with one HFM directly deposited on the suction surface near the leading edge. Simultaneous velocity measurements are made above the heat flux sensors using miniature hot wire probes. Grids are used to produce two turbulence fields of constant inlet turbulence intensity, Tu=5%, but significantly different integral length scales (Ax). Results are compared with a low free stream turbulence baseline condition. Special emphasis is given to frequency domain analysis of the data via coherence function magnitude and phase, energy spectra, and time auto and cross correlations.
Download or read book Paper written by and published by . This book was released on 2001 with total page 492 pages. Available in PDF, EPUB and Kindle. Book excerpt:
