Compressible Laminar Boundary Layer Over a Yawed Infinite Cylinder With Heat Transfer and Arbitrary Prandtl Number (open access)

Compressible Laminar Boundary Layer Over a Yawed Infinite Cylinder With Heat Transfer and Arbitrary Prandtl Number

"The equations are presented for the development of the compressible laminar boundary layer over a yawed infinite cylinder. For compressible flow with a pressure gradient the chordwise and spanwise flows are not independent. Using the Stewartson transformation and a linear viscosity-temperature relation yields a set of three simultaneous ordinary differential equations in a form yielding similar solutions. These equations are solved for stagnation-line flow for surface temperatures from zero to twice the free-stream stagnation temperature and for a wide range of yaw angle and free-stream Mach number" (p. 1017).
Date: April 4, 1957
Creator: Reshotko, Eli & Beckwith, Ivan E.
System: The UNT Digital Library
Direct method of design and stress analysis of rotating disks with temperature gradient (open access)

Direct method of design and stress analysis of rotating disks with temperature gradient

A method is presented for the determination of the contour of disks, typified by those of aircraft gas turbines, to incorporate arbitrary elastic-stress distributions resulting from either centrifugal or combined centrifugal and thermal effects. The specified stress may be radial, tangential, or any combination of the two. Use is made of the finite-difference approach in solving the stress equations, the amount of computation necessary in the evolution of a design being greatly reduced by the judicious selection of point stations by the aid of a design chart. Use of the charts and of a preselected schedule of point stations is also applied to the direct problem of finding the elastic and plastic stress distribution in disks of a given design, thereby effecting a great reduction in the amount of calculation. Illustrative examples are presented to show computational procedures in the determination of a new design and in analyzing an existing design for elastic stress and for stresses resulting from plastic flow.
Date: April 4, 1949
Creator: Manson, S. S.
System: The UNT Digital Library
Lubrication and cooling studies of cylindrical-roller bearings at high speeds (open access)

Lubrication and cooling studies of cylindrical-roller bearings at high speeds

The results of an experimental investigation of the effect of oil inlet distribution and oil inlet temperature on the inner and outer-race temperatures of 75-millimeter-bore (size 215) cylindrical-roller inner-race-riding cage-type bearings are reported. A radial-load test rig was used over a range of dn values (product of the bearing bore in mm and the shaft speed in r.p.m) from 0.3 x 10(5) to 1.2 x 10(6) and static radial loads from 7 to 1113 pounds.
Date: April 4, 1951
Creator: Macks, E. Fred & Nemeth, Zolton N.
System: The UNT Digital Library
Pressure-distribution measurements at large angles of pitch on fins of different span-chord ratio on a 1/40-scale model of the U. S. Airship "Akron" (open access)

Pressure-distribution measurements at large angles of pitch on fins of different span-chord ratio on a 1/40-scale model of the U. S. Airship "Akron"

Report presents the results of pressure-distribution measurements on a 1/40-scale model of the U. S. Airship "Akron" conducted in the NACA 20-foot wind tunnel. The measurements were made on the starboard fin of each of four sets of horizontal tail surfaces, all of approximately the same area but differing in span-chord ratio, for five angles of pitch varying from 11.6 degrees to 34 degrees, for four elevator angles, and at air speeds ranging from 56 to 77 miles per hour. Pressures were also measured at 13 stations along the rear half of the port side of the hull at one elevator setting for the same five angles of pitch and at an air speed of approximately 91 miles per hour. The normal force on the fin and the moment of forces about the fin root were determined. The results indicate that, ignoring the effect on drag, it would be advantageous from structural considerations to use a fin of lower span-chord ratio than that used on the "Akron.".
Date: April 4, 1937
Creator: McHugh, James G.
System: The UNT Digital Library