Download or read book An Experimental Investigation of the Supersonic Axisymmetric Base Flow Behind a Cylindrical Afterbody written by Jeff Lee Herrin and published by . This book was released on 1991 with total page 208 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Experimental Investigation of Supersonic Axisymmetric Base Flows Including the Effects of Afterbody Boattailing written by Jeff Lee Herrin and published by . This book was released on 1993 with total page 476 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Experimental Investigation of Supersonic Flow Over Axisymmetric Afterbodies with a Centered Propulsive Jet at Angles of Attack written by Johan Agrell and published by . This book was released on 1985 with total page 96 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Experimental Investigation of the Effects of Base Bleed in Axisymmetric Supersonic Flow written by Tarun Mathur and published by . This book was released on 1996 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt: Base bleed is a technique wherein a small quantity of fluid is injected into the base region of a projectile to reduce the base drag. The effects of base bleed on the near-wake flowfield of a cylindrical afterbody in a Mach 2.5 flow have been investigated in the present study. This experimental study is aimed at better understanding the complex fluid dynamic interactions occurring in the near-wake due to base bleed and is motivated by the lack of detailed velocity and turbulence data in this flowfield. The experimental techniques used include static pressure measurements, schlieren and shadowgraph photography, and two-component laser Doppler velocimetry (LDV). The comprehensive LDV mean velocity and turbulence measurements obtained during this study provide valuable insight into the physics of the base bleed mechanism and constitute a benchmark data set to aid analytical and computational efforts in modeling and predicting supersonic base flows. Static pressure measurements show that with increasing bleed flow rate, the average base pressure increases initially, attains a peak value near an injection parameter of I = 0.0148, and then decreases with further increase in I. The peak base pressure ratio at the optimum bleed condition is 18.5% higher than the blunt base case and 5.7% higher than for a 5 degree boattailed afterbody. Axial LDV traverses show peaks in turbulent kinetic energy along the centerline at the forward and rear stagnation point locations. Centerline measurements also indicate the near-disappearance of the primary recirculation region near the optimum bleed condition. Detailed mean velocity and turbulence data were obtained in the entire near-wake flowfield for three different bleed cases corresponding to low bleed, slightly pre-optimal bleed, and slightly post-optimal bleed conditions. These measurements indicate that the bleed flow provides at least some of the fluid required for shear layer entrainment and shields the base annulus from the outer shear layer and the primary recirculation region, leading to an increase in base pressure. There is an overall reduction in turbulence levels throughout the base bleed flowfields relative to the near-wake flowfields of blunt-based and boattailed afterbodies. With increasing bleed, the formation of a strong bleed jet shear layer and secondary recirculation region near the base annulus offsets the benefits of base bleed, leading to a drop in the base pressure. At all bleed conditions, the normal stress distribution is highly anisotropic with the axial component dominating the near-wake turbulence field. The net benefits of base bleed are maximized at the optimum bleed condition, which corresponds to the highest base pressure, the disappearance of the primary recirculation region, and the lowest turbulence and entrainment levels in the near-wake flowfield.
Download or read book Supersonic Base Flow Experiments in the Near wake of a Cylindrical Afterbody written by J. L. Herrin and published by . This book was released on 1993 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An Experimental Investigation of the Influence from Controls on Supersonic Axisymmetric Flow Over Afterbodies with a Centered Propulsive Jet written by Johan Agrell and published by . This book was released on 1982 with total page 43 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Research in Progress written by and published by . This book was released on 1992 with total page 302 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book 93 3000 93 3034 written by and published by . This book was released on 1993 with total page 524 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book An experimental investigation of planar turbulent supersonic base flow with mass bleed written by Gordon Lee Thorn and published by . This book was released on 1970 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Experimental And Theoretical Investigation Of The Near Wake In An Axisymmetric Supersonic Flow With And Without Base Injection written by Ramlala P. Sinha and published by . This book was released on 1967 with total page 197 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book 25th AIAA Fluid Dynamics Conference written by and published by . This book was released on 1994 with total page 584 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Analysis of the Axisymmetric Base Pressure and Base Temperature Problem with Supersonic Interacting Freestream Nozzle Flows Based on the Flow Model of Korst Et Al Part III A Computer Program and Representative Results for Cylindrical Boattailed Or Flared Afterbodies written by A. L. Addy and published by . This book was released on 1970 with total page 144 pages. Available in PDF, EPUB and Kindle. Book excerpt: The computer program presented and discussed in Part 1 of this report for analyzing the axisymmetric base-pressure and base-temperature problem with interacting supersonic free-stream and propulsive-nozzle flows was improved and generalized to include the analysis of an afterbody upstream of the base region. The afterbody geometries considered are: cylindrical, conical, parabolic, and tangent-ogive boattails and conical flares. The F0RTRAN IV computer-program listing, as well as detailed information on program development, organization, and usage, are included. Theoretical afterbody and base-pressure results are presented for parametric variations in afterbody geometry and flow variables. In addition, a limited comparison between theoretical and experimental conical- afterbody and base-pressure data is made.
Download or read book Numerical Investigation of Supersonic Base Flow with Base Bleed written by and published by . This book was released on 1995 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: A zonal, implicit, time-marching Navier-Stokes computational technique has been used to compute the turbulent supersonic base flow over a cylindrical afterbody with base bleed. A critical element of calculating such flows is the turbulence model. Two eddy viscosity turbulence models have been used in the base region flow computations. These models include an algebraic turbulence model and a two-equation k-e model. The k-e equations are solved using an implicit algorithm, and calculations with the k-e model are extended up to the wall. Flow field computations have been performed for a cylindrical afterbody at M approx. = 2.46 and at an angle of attack of a = 0. The results are compared to the experimental data for the same conditions and the same configuration. Details of the mean flow field as well as the turbulence quantities have been presented. In addition, the computed base pressure distribution has been compared with the experiment. In general, the k-e turbulence model performs better in the near wake than the algebraic model and predicts the base pressure much better.
Download or read book Numerical Investigation of Supersonic Base Flow with Base Bleed written by and published by . This book was released on 1995 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: A zonal, implicit, time-marching Navier-Stokes computational technique has been used to compute the turbulent supersonic base flow over a cylindrical afterbody with base bleed. A critical element of calculating such flows is the turbulence model. Two eddy viscosity turbulence models have been used in the base region flow computations. These models include an algebraic turbulence model and a two-equation k-e model. The k-e equations are solved using an implicit algorithm, and calculations with the k-e model are extended up to the wall. Flow field computations have been performed for a cylindrical afterbody at M approx. = 2.46 and at an angle of attack of a = 0. The results are compared to the experimental data for the same conditions and the same configuration. Details of the mean flow field as well as the turbulence quantities have been presented. In addition, the computed base pressure distribution has been compared with the experiment. In general, the k-e turbulence model performs better in the near wake than the algebraic model and predicts the base pressure much better.
Download or read book 29th AIAA Fluid Dynamics Conference written by and published by . This book was released on 1998 with total page 540 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Base Bleed written by Kenneth K. Kuo and published by Taylor & Francis. This book was released on 1991 with total page 336 pages. Available in PDF, EPUB and Kindle. Book excerpt: Includes papers presented at a symposium, which represent the state-of-the-art in the development of base bleed projectiles and related research, and are from recognized experts in the field. The papers have undergone a thorough review process.
Download or read book 92 4338 to 92 4494 written by and published by . This book was released on 1992 with total page 496 pages. Available in PDF, EPUB and Kindle. Book excerpt:
