Search NASA⌕ Search

SEARCH · Search NASA

Results for “NACA”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1955

High-Speed Cascade Tests of the NACA 65-(12A(sub 10))10 and NACA 65-(12A(sub 2)I(sub 8b))10 Compressor Blade Sections

Two-dimensional porous-well cascade tests of the NACA 65- (l2Al0) 10 and NACA 65-(l2A2I8b)10 blade sections were made at Mach numbers from 0.3 to choking in most cases. Data were obtained at solidities of 1.0 and 1.5 et inlet-air angles of 45 deg. and 60 deg. for both blade sections. With a solid--wall modification to the cascade tunnel, schlieren observations were made of the flow in cascade at a solidity of 1.5 and inlet-air angle of 45 deg. and at a solidity of 1.0 and inlet-air angle of 60 deg. Test results for the NACA 65-(12A10)l0 blade section show t hat the turning angles measured at low speed do not change significantly as the speed increases until the critical Mach number is exceed. Because of increasing separation from the highly cambered trailing-edge region, the turning angles for the NACA 65-(12A2I8b)10 blade section decreased as much as 4 deg. from low speed to critical speed. The high-speed performance of the NACA 65-(12A10)10 and the NACA 65-(12A2I8b)l0 blade sections is largely determined by the passage area distribution. The angle of attack for best operation at high Mach numbers is higher than the design angle of attack selected at low speed to have pressure distributions that are free of peaks.

Dunavant, James C.↗
NASA NTRS1987

An experimental low Reynolds number comparison of a Wortmann FX67-K170 airfoil, a NACA 0012 airfoil and a NACA 64-210 airfoil in simulated heavy rain

Wind tunnel experiments were conducted on Wortmann FX67-K170, NACA 0012, and NACA 64-210 airfoils at rain rates of 1000 mm/hr and Reynolds numbers of 310,000 to compare the aerodynamic performance degradation of the airfoils and to attempt to identify the various mechanisms which affect performance in heavy rain conditions. Lift and drag were measured in dry and wet conditions, a variety of flow visualization techniques were employed, and a computational code which predicted airfoil boundary layer behavior was used. At low angles of attack, the lift degradation in wet conditions varied significantly between the airfoils. The Wortmann section had the greatest overall lift degradation and the NACA 64-210 airfoil had the smallest. At high angles of attack, the NACA 64-210 and 0012 airfoils had improved aerodynamic performance in rain conditions due to an apparent reduction of the boundry layer separation. Performance degradation in heavy rain for all three airfoils at low angles of attack could be emulated by forced boundary layer transition near the leading edge. The secondary effect occurs at time scales consistent with top surface water runback times. The runback layer is thought to effectively alter the airfoil geometry. The severity of the performance degradation for the airfoils varied. The relative differences appeared to be related to the susceptibility of each airfoil to premature boundary layer transition.

Craig, Anthony P.↗
NASA NTRS1947

The Effect of High Solidity on Propeller Characteristics at High Forward Speeds from Wind-Tunnel Tests of the NACA 4-(3)(06.3)-06 and NACA 4-(3)(06.4)-09 Two-Blade Propellers

Tests of two-blade propellers having the NACA 4-(3)(06.3)-06 and NACA 4-(3)(06.4)-09 blade designs (blade activity factors of 179 and 263, respectively) have been made in the Langley 8-foot high-speed tunnel through a range of blade angle from 20 degrees to 70 degrees for free-stream Mach numbers from 0.165 to 0.725 to determine the effects of high solidity and compressibility on propeller characteristics. The tests are part of a general investigation of propellers at high forward speeds. Results previously reported for similar tests of two-blade propellers having the NACA 4-308-03 and NACA 4-308-045 blade designs (blade activity factors of 87 and 133, respectively) are included for comparison. The results showed that the 0.06- and 0.09-solidity blades, although producing efficiencies of the order of 90 percent, were less efficient than blades of conventional solidity. The variation in average blade lift coefficient with solidity at a constant blade angle and advance-diameter ratio through the speed range of these tests was found to be analogous to the variation of wing lift coefficient with aspect ratio, indicating that high-solidity blades may be desirable at very high speeds. Because of power limitations of the test equipment, conclusive evidence of the possible favorable effects of increased blade solidity at high speeds was not obtained. Further tests are desirable.

Delano, James B.↗
NASA NTRS1953

Aerodynamic Characteristics of a Two-blade NACA 10-(3)(062)-045 Propeller and of a Two-blade NACA 10-(3)(08)-045 Propeller

Characteristics are given for the two-blade NACA 10-(3)(062)-045 propeller and for the two-blade NACA 10-(3)(08)-045 propeller over a range of advance ratio from 0.5 to 3.8, through a blade-angle range from 20 degrees to 55 degrees measured at the 0.75 radius. Maximum efficiencies of the order of 91.5 to 92 percent were obtained for the propellers. The propeller with the thinner airfoil sections over the outboard portion of the blades, the NACA 10-(3)(062)-045 propeller, had lower losses at high tip speeds, the difference amounting to about 5 percent at a helical tip Mach number of 1.10.

BLADE SECTIONS-PROPELLERS↗
NASA NTRS1937

Aerodynamic Characteristics of NACA 23012 and 23021 Airfoils with 20-Percent-chord External-Airfoil Flaps of NACA 23012 Section

Report presents the results of an investigation of the general aerodynamic characteristics of the NACA 23012 and 23021 airfoils, each equipped with a 0.20c external flap of NACA 23012 section. The tests were made in the NACA 7 by 10-foot and variable-density wind tunnels and covered a range of Reynolds numbers that included values corresponding to those for landing conditions of a wide range of airplanes. Besides a determination of the variation of lift and drag characteristics with position of the flap relative to the main airfoil, complete aerodynamic characteristics of the airfoil-flap combination with a flap hinge axis selected to give small hinge moments were measured in the two tunnels. Some measurements of air loads on the flap itself in the presence of the wing were made in the 7 by 10-foot wind tunnel.

Platt, Robert C↗
NASA NTRS1951

Investigation of the NACA 4-(5)(08)-03 and NACA 4-(10)(08)-03 Two-Blade Propellers at Forward Mach Numbers to 0.725 to Determine the Effects of Camber and Compressibility on Performance

As part of a general investigation of propellers at high forward speeds, tests of two-blade propellers having the NACA 4-(5)(08)-03 and NACA 4-(10)(08)-03 blade designs were made in the Langley 8-foot high-speed tunnel through a range of blade angle from 20 degrees to 60 degrees for forward Mach numbers from 0.165 to 0.70 to determine the effect of camber and compressibility on propeller characteristics. Results previously reported for similar tests of a two-blade propeller having the NACA 4-(3)(08)-03 blade design are included for comparison.

Delano, James B↗
NASA NTRS1974

Low speed aerodynamic characteristics of NACA 6716 and NACA 4416 airfoils with 35 percent-chord single-slotted flaps

An investigation was conducted in a low-turbulence pressure tunnel to determine the two-dimensional lift and pitching-moment characteristics of an NACA 6716 and an NACA 4416 airfoil with 35-percent-chord single-slotted flaps. Both models were tested with flaps deflected from 0 deg to 45 deg, at angles of attack from minus 6 deg to several degrees past stall, at Reynolds numbers from 3.0 million to 13.8 million, and primarily at a Mach number of 0.23. Tests were also made to determine the effect of several slot entry shapes on performance.

Bingham, G. J.↗
NASA NTRS1986

Aerodynamic data banks for Clark-Y, NACA 4-digit and NACA 16-series airfoil families

With the renewed interest in propellers as means of obtaining thrust and fuel efficiency in addition to the increased utilization of the computer, a significant amount of progress was made in the development of theoretical models to predict the performance of propeller systems. Inherent in the majority of the theoretical performance models to date is the need for airfoil data banks which provide lift, drag, and moment coefficient values as a function of Mach number, angle-of-attack, maximum thickness to chord ratio, and Reynolds number. Realizing the need for such data, a study was initiated to provide airfoil data banks for three commonly used airfoil families in propeller design and analysis. The families chosen consisted of the Clark-Y, NACA 16 series, and NACA 4 digit series airfoils. The various component of each computer code, the source of the data used to create the airfoil data bank, the limitations of each data bank, program listing, and a sample case with its associated input-output are described. Each airfoil data bank computer code was written to be used on the Amdahl Computer system, which is IBM compatible and uses Fortran.

Korkan, K. D.↗
NASA NTRS1987

Comparative low Reynolds number tests of NACA 64-210, NACA 0012, and Wortmann FX67-K170 airfoils in heavy rain

The effect of simulated rain at 1000 mm/h on the aerodynamic performance of NACA 64-210, NACA 0012, and Wortmann FX67-K170 airfoils is investigated experimentally at Reynolds number 310,000, freestream velocity 70 mph, and angle of attack -10 to +20 deg in the 1 x 1-ft section of the MIT low-turbulence wind tunnel. The results are presented graphically and characterized in detail. Rain is found to produce lift degradation of 5-25 percent, an effect attributed to development of a premature transition at the leading edge followed (after 1-10 s) by alteration of the profile by surface water runback.

Hansman, R. John, Jr.↗
NASA NTRS1948

An Investigation of Aileron Oscillations at Transonic Speeds on NACA 23012 and NACA 65-212 Airfoils by the Wing-flow Method

An investigation is being conducted to determine the feasibility of studying aileron buzz by means of the wing-flow method. Two semispan models which had an aspect ratio of 6 and a taper ratio of 2 with quarter-chord half-span mass-balanced ailerons have been used. One had an NACA 23012 airfoil section and the second, an NACA 65-212 airfoil section. The ailerons on both models were subject to buzz over a small range of Mach number near 0.9. Data obtained by wing-flow testing agreed reasonably well with full-scale flight results.

MACH NUMBER EFFECTS - COMPLETE WINGS↗
NASA NTRS1938

Pressure distribution over an NACA 23012 airfoil with an NACA 23012 external-airfoil flap

Report presents the results of pressure-distribution tests of an NACA 23012 airfoil with an NACA 23012 external airfoil flap made in the 7 by 10-foot wind tunnel. The pressures were measured on the upper and lower surfaces at one chord section on both the main airfoil and on the flap for several different flap deflections and at several angles of attack. A test installation was used in which the airfoil was mounted horizontally in the wind tunnel between vertical end planes so that two-dimensional flow was approximated. The data are presented in the form of pressure-distribution diagrams and as graphs of calculated coefficients for the airfoil-and-flap combination and for the flap alone.

Wenzinger, Carl J↗
NASA NTRS1948

NACA Conference on Turbojet-Engine Thrust Augmentation Research: A Compilation of the Papers Presented by NACA Staff Members

The conference on Turbojet-Engine Thrust-Augmentation Research was organized by the NACA to present in summarized form the results of the latest experimental and analytical investigations conducted at the Lewis Flight Propulsion Laboratory on methods of augmenting the thrust of turbojet engines. The technical discussions are reproduced herewith in the same form in which they were presented. The original presentation in this record are considered as complementary to, rather than substitutes for, the committee's system of complete and formal reports.

Source record↗
NASA NTRS1947

Longitudinal Stability and Control Characteristics of a Semispan Model of the XF7U-1 Tailless Airplane at Transonic Speeds by the NACA Wing-Flow Method, TED No. NACA DE307

An investigation was made by the NACA wing-flow method to determine the longitudinal stability and control characteristics at transonic speeds of a semispan model of the XF7U-1 tailless airplane. The 25-percent chord line of the wing of the model was swept back 35 deg. The airfoil sections of the wing perpendicular to the 25-percent chord line were 12 percent thick. Measurements were made of the normal force and pitching moment through an angle-of-attack range from about -3 deg to 14 deg for several ailavator deflections at Mach numbers from 0.65 to about 1.08. The results of the tests indicated no adverse effects of compressibility up to a Mach number of at least 0.85 at low normal-force coefficients and small ailavator deflections. Up to a Mach number of 0.85, the neutral point at low normal-force coefficients was at about 25 percent of the mean aerodynamic chord and moved rearward irregularly to 41 or 42 percent with a further increase in Mach number to about 1.05. For deflections up to -8.0 percent, the ailavator was effective in changing the pitching moment except at Mach numbers from 0.93 to about 1.0 where ineffectiveness or reversal was indicated for deflections and normal-force coefficients. With -13.2 deg deflection at normal-force coefficients above about 0.3, reversal of ailavator effectiveness occurred at Mach numbers as low as 0.81. A nose-down trim change, which began at a Mach number of about 0.85, together with the loss in effectiveness of the ailavator, indicated that with increase in the Mach number from about 0.95 to 1.05 an abrupt ailavator movement of 5 deg or 6 deg first up and then down would be required to maintain level flight.

Sawyer, Richard H.↗
NASA NTRS1950

Effect of Various Modifications on Drag and Longitudinal Stability and Control Characteristics at Transonic Speeds of a Model of the XF7U-1 Tailless Airplane: NACA Wing-FLow Method, TED No. NACA DE 307

An investigation was made by the NACA wing-flow method to determine the drag, pitching-moment, lift, and angle-of-attack characteristics at transonic speeds of various configurations of a semispan model of an early configuration of the XF7U-1 tailless airplane. The results of the tests indicated that for the basic configuration with undeflected ailavator, the zero-lift drag rise occurred at a Mach number of about 0.85 and that about a five-fold increase in drag occurred through the transonic speed range. The results of the tests also indicated that the drag increment produced by -8.0 degrees deflection of the ailavator increased with increase in normal-force coefficient and was smaller at speeds above than at speeds below the drag rise. The drag increment produced by 35 degree deflection of the speed brakes varied from 0.040 to 0.074 depending on the normal-force coefficient and Mach number. These values correspond to drag coefficients of about 0.40 and 0.75 based on speed-brake frontal area. Removal of the fin produced a small positive drag increment at a given normal-force coefficient at speeds during the drag rise. A large forward shift of the neutral-point location occurred at Mach numbers above about 0.90 upon removal of the fin, and also a considerable forward shift throughout the Mach number range occurred upon deflection of the speed brakes. Ailavator ineffectiveness or reversal at low deflections, similar to that determined in previous tests of the basic configuration of the model in the Mach number range from about 0.93 to 1.0, was found for the fin-off configuration and for the model equipped with skewed (more highly sweptback) hinge-line ailavators. With the speed brakes deflected, little or no loss in the incremental pitching moment produced by deflection of the ailavator from O degrees to -8.00 degrees occurred in the Mach number range from 0.85 to 1.0 in contrast to a considerable loss found in previous tests with the speed brakes off.

Sawyer, Richard H.↗