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  • Aircraft Propulsion and Power  (15)
  • Pflanzenschädling  (13)
  • Biology
  • 42.75
  • 1950-1954  (28)
  • 1953  (11)
  • 1950  (17)
Collection
Years
  • 1950-1954  (28)
Year
  • 1
    facet.materialart.
    Unknown
    In:  Nachrichtenblatt des deutschen Pflanzenschutzdienstes 5, Nr.10; p.145-150
    Publication Date: 1953
    Description: Der Autor untersuchte die für das Auftreten des weißen Bärenspinners günstigen Temperaturen im ehemaligen Jugoslawien (Palic, Vojvodina) und Österreich (Burgenland) und identifizierte die Temperaturen von Mai bis August als wichtige Einflußfaktoren auf die Entwicklungszeit des Falters. Hierdurch konnten Temperaturen identifiziert werden bei denen eine, zwei oder sogar drei Generationen im Jahresverlauf vorkommen können. Sobald die Temperaturen 14-15°C überschreiten, kann die Entwicklung der ersten Generation beginnen. Die gewonnenen Erkenntnisse wurden dazu eingesetzt, um das Ausbreitungspotential des Schmetterlings aufgrund klimatischer Parameter nach Mitteleuropa abzuschätzen. KATASTER-BESCHREIBUNG: KATASTER-DETAIL:
    Keywords: Jugoslawien, Österreich, Deutschland ; 1946-1952 ; Pflanzenschädling ; Temperatur
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  • 2
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    In:  Anz. Schädlingskunde 26, p. 49-51
    Publication Date: 1953
    Description: Untersuchungen zum durch Spinnmilben (Tetranychus althaeae v. hanst.) an Zuckerrüben verursachten Schadbild je nach der Befallsintensität KATASTER-BESCHREIBUNG: - KATASTER-DETAIL: -
    Keywords: Diendorf, Österreich ; 1952 ; Zuckerrüben ; Pflanzenschädling
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  • 3
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    In:  Beiträge zur Entomologie, Band 3, p. 518-529
    Publication Date: 1953
    Description: Untersuchungen zum Ausbleiben des erwarteten starken Befalls im Herbst 1952 und Vergleich mit bereits veröffentlichten Erkenntnissen zum Massenwechsel des Rapserdflohs; KATASTER-BESCHREIBUNG: Abhängigkeit des Massenwechsels des Rapserdflohs von der Witterung (Temperatur) KATASTER-DETAIL: Delta T -: Delta T (August, September) -, dann Zuwanderung der Rapserdflöhe -;
    Keywords: Sachsen-Anhalt ; 1951-1953 ; Pflanzenschädling ; Temperatur ; Witterung ; Raps
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  • 4
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    In:  Der Obstanbau, p. 184-185
    Publication Date: 1953
    Description: Beobachtungen zur Masseneinablage und zur Witterung KATASTER-BESCHREIBUNG: Zusammenhang zischen der Luftfeuchtigkeit und dem Flug sowie der Eiablage des Apfelwicklers KATASTER-DETAIL: Delta Relf (Trockenperioden) +, dann Flug + und Eiablage +
    Keywords: Deutschland ; 1952 ; Pflanzenschädling ; Trockenheit
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  • 5
    Publication Date: 1953
    Description: Beobachtungen zu den wichtigsten Massenwechselphasen, welche phänologisch mit Hilfe der Temperatursummenregel ausgewertet wurden sowie Beobachtungen zum Einfluss des Mikroklimas auf die Flugphase KATASTER-BESCHREIBUNG: Zusammenhang zwischen den wichtigsten Massenwechselperioden und der Temperatur, angegeben mit der mittleren Temperatursumme ab dem Eintritt des Vorfrühlings (Schneeglöckchenblüte); Einfluss von flugbegrenzenden Faktoren (Licht, Wind, Niederschlag) und flugbeeinflussenden Faktoren (Temperatur, Luftfeuchtigkeit) KATASTER-DETAIL: Temperatursumme = 160°C, dann Schlüpfen der ersten Fundatrixlarven; Temperatursumme = 360°C, dann Eintreten erster reifer Fundatrizen; Temperatursumme = 600°C, dann Reife der ersten fundatrigenen Fliegen und Anfang des fundatrigenen Zufluges; Temperatursumme = 1000-1050°C, dann Ende des fundatrigenen Zufluges und Anfang des virginogenen Zufluges; temperatursumme = 2280-2420°C, dann Ende des virginogenen Zufluges; Delta Lichtintensität + und Windgeschwindigkeit 〈 0,6m/s und T(Blattoberfläche ) 〉= 17°C, bzw. T (Luft) 〉= 15-16°C und Delta Nied -, dann Abflug +; Delta T +, dann Ablfug +, T 〉 20-26°C, dann Abflug -; Relf = 60%, dann optimaler Bereich für Abflug;
    Keywords: Quedlinburg, Thüringen ; 1949-1952 ; Luftfeuchte ; Klima ; Korrelationsmethode ; Niederschlag ; Pflanzenschädling ; Phänologie ; Temperatur ; Wind ; Witterung
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  • 6
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    In:  Nachrichtenblatt für den deutschen Pflanzenschutzdienst, p. 143-148
    Publication Date: 1953
    Description: Bericht über die Untersuchungen zur Frage der Abhängigkeit der Imagines von klimatischen Faktoren KATASTER-BESCHREIBUNG: Einfluss der Witterung (Temperatur, Wind, Sonnenscheindauer, Luftfeuchte) auf die Flugaktivität KATASTER-DETAIL: Delta T +: T= 18°C, dann Höchstwert an geschlüpften und geschlechtsreifen Käfern; T 〉 18°C oder T 〈 18°C, dann Zahl an geschlüpften und geschlechtsreifen Käfern -; Delta Sonn +, dann Flugaktivität +; T = 23°C und Relf = 70%, dann Optimum der Flugaktivität; T = 13°C, dann Flugaktivität verhindert Delta Wind +: Wind 〉 1m/s, dann Flugaktivität vermindert, Wind 〉 2m/s, dann Flugaktivität stark gehemmt
    Keywords: Sachsen-Anhalt ; 1951-1952 ; Insekten ; Luftfeuchte ; Korrelationsmethode ; Niederschlag ; Pflanzenschädling ; Temperatur ; Wind ; Witterung ; Sonnenscheindauer
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  • 7
    Publication Date: 2019-09-20
    Description: The performance of a two-stage turbine with variable-area first-stage turbine nozzles was determined in the NACA Lewis altitude wind tunnel over a range of simulated altitudes from 15,000 to 44,000 feet and engine speeds from 50 to 100 percent of rated speed. The variable-area turbine nozzles used in this investigation were primarily a test device for compressor research purposes and were not necessarily of optimum aerodynamic design. The results of this investigation are indicative of effects of turbine-nozzle-area variation on turbine performance within the operating range allowed by the engine. The variable-area turbine nozzles were found to be mechanically reliable and to have negligible leakage losses. Increasing the turbine-nozzle-throat area from 1.15 to 1.67 square feet increased the corrected turbine gas flow or effective turbine nozzle area about 10 percent. At a given corrected turbine speed and turbine pressure ratio, changing the turbine nozzle area from 1.30 to 1. 67 square feet lowered the turbine efficiency 3 or 4 percent. The effect of increasing the turbine nozzle area from 1.15 to 1.67 square feet (decreasing the turning angle about 7 1/2 degrees) would be to lower the turbine efficiency about 5 or 6 percent.
    Keywords: Aircraft Propulsion and Power
    Type: NACA-RM-E52J20
    Format: application/pdf
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  • 8
    Publication Date: 2019-07-12
    Description: The performance of a 13-stage development comressor for the J40-WE-24 engine has been determined at equivalent speeds from 30 to 112 percent of design. The design total-pressure ratio of 6.0 and the design weight flow of 164 pounds per second were not attained, An analysis was conducted to determine the reasons for the poor performance at the design and over-design speed. The analysis indicated that most of the difficulty could be attributed to the fact that the first stage was overcompromised to favor part-speed performance,
    Keywords: Aircraft Propulsion and Power
    Type: NACA-RM-SE53D17
    Format: application/pdf
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  • 9
    Publication Date: 2019-07-12
    Description: Altitude performance of a YJ71-A-7 turbojet engine, with afterburner inoperative, was determined in the NACA Lewis altitude wind tunnel over a wide range of flight conditions. Engine speed and exhaust-nozzle area were controlled independently during this investigation. The variation of corrected values of air flow, net thrust, and fuel flow with corrected engine speed was not defined by a single curve with changes in altitude at given flight Mach number. Changes in altitude had very little effect on minimum specific fuel consumption at altitudes up to 45,000 feet. There is one exhaust-nozzle schedule that is nearly optimum for all flight conditions. Performance calculated from pumping characteristics agreed with experimental values and can therefore be used to extend engine performance data.
    Keywords: Aircraft Propulsion and Power
    Type: NACA-RM-E53E13
    Format: application/pdf
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  • 10
    Publication Date: 2019-07-12
    Description: A program was undertaken to determine the J73 turbojet engine compressor stall and surge characteristics and combustor blow-out limits encountered during transient engine operation. Data were obtained in the form of oscillograph traces showing the time history of several engine performance parameters with changes in engine fuel flow. The data presented in this report are for step changes in fuel flow at an altitude of 35,000 feet, at flight Mach numbers of 0.3, 0.8, and 1.2, and at several engine-inlet temperatures,
    Keywords: Aircraft Propulsion and Power
    Type: NACA-RM-SE53F29
    Format: application/pdf
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  • 11
    Publication Date: 2019-07-12
    Description: A program was undertaken to determine the J73 turbojet engine compressor stall and surge characteristics and combustor blow-out limits enc ountered during transient engine operation. Data were obtained in the form of oscillograph traces showing the time history of several engi ne parameters with changes in engine fuel flow. The data presented in this report are for step and ramp changes in fuel flow at an altitude of 45,000 feet and flight Mach numbers of 0 and 0.8.
    Keywords: Aircraft Propulsion and Power
    Type: NACA-RM-SE53F30
    Format: application/pdf
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  • 12
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    Unknown
    In:  Mitteilungen aus der Biologischen Zentralanstalt für Land- und Forstwirtschaft, Berlin-Dahlem, Heft 69
    Publication Date: 1950
    Description: Bericht über die Ergebnisse der Untersuchungen zu den Wechselwirkungen zwischen Larve und Wirtspflanze KATASTER-BESCHREIBUNG: Einfluss der Temperatur auf den Larvenbefall KATASTER-DETAIL: Delta T -, dann Entwicklungsdauer der Larven +; T 〉 0°C, dann Froststarre und Wanderfähigkeit -; Delta T - und Delta Relf +, dann Larvenmortalität +
    Keywords: Berlin-Dahlem ; 1948-1949 ; Insekten ; Luftfeuchte ; Pflanzenschädling ; Temperatur ; Raps
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  • 13
    facet.materialart.
    Unknown
    In:  Nachrichtenblatt des deutschen Pflanzenschutzdienstes 2.Jahrg., Nr.11; p.161-165
    Publication Date: 1950
    Description: In Freilandversuchen wurden Temperaturen ermittelt, bei denen Kartoffelkäfer den Boden im Frühjahr verlassen. Zudem wurden Minimalwerte für das Überleben in verschiedenen Bodenarten ermittelt. KATASTER-BESCHREIBUNG: Ein kritischer Wert der Bodentemperatur wurde für das massenhafte Verlassen des Bodens durch den Kartoffelkäfer ermittelt. Allerdings wurden auch bei 12,5°C Bodentemperatur bereits Kartoffelkäfer an der Oberfläche beobachtet. KATASTER-DETAIL: Kritischer Wert= 16,6°C Bodentemperatur (in 50cm Tiefe)
    Keywords: Heidelberg ; 1949-1950 ; Kartoffeln ; Pflanzenschädling ; Hackfrüchte
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  • 14
    facet.materialart.
    Unknown
    In:  Zeitschrift für Pflanzenbau und Pflanzenschutz, p. 241-266
    Publication Date: 1950
    Description: Untersuchungen zur Verbreitung und zum Massenwechsel der grünen Pfirsichblattlaus hinsichtlich der Faktoren Wind und Thermik KATASTER-BESCHREIBUNG: Zusammenhang zwischen Massenvermehrung der Laus und Morphologie sowie meteorologischen Verhältnissen der Landschaft KATASTER-DETAIL: Wind +, dann Pfirsichblattlaus Wanderung +; Wind +, dann Strecke +; Sonneneinstrahlung +, dann Ausbreitung +; Nied +, dann Ausbreitung -;
    Keywords: Bayern ; 1950 ; Insekten ; Pflanzenschädling ; Wind ; Witterung
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  • 15
    Publication Date: 1950
    Description: Untersuchungen zur Schlüpfzeit, der Generationszahl und der Abflugzeiten von Myzodes persicae Sulzer am Pfirsichbaum KATASTER-BESCHREIBUNG: Zusammenhang zwischen Klima, Witterung und Schlüpfablauf von Myzodes persicae KATASTER-DETAIL: Delta T -, dann Verzögerung im Schlüpfablauf
    Keywords: Bonn ; 1947-1950 ; Kartoffeln ; Pflanzenschädling ; Temperatur
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  • 16
    facet.materialart.
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    In:  Nachrichtenblatt des Deutschen Pflanzenschutzdienstes, p. 171-172
    Publication Date: 1950
    Description: Bericht über die Beobachtungen zur Entwicklung und zum Auftreten der Möhrenfliege unter dem Einfluss der Witterung und der Lage KATASTER-BESCHREIBUNG: Einfluss der Witterung und der Lage auf die Befallsstärke der Fliege KATASTER-DETAIL: Delta Lichtintensität +, dann Möhrenfliegenbefall -; Delta Nied +, dann Entwicklung der Maden +; Delta Wind +, dann Befall -
    Keywords: Schleswig-Holstein ; 1948-1949 ; Insekten ; Niederschlag ; Pflanzenschädling ; Temperatur ; Trockenheit ; Wind ; Witterung ; Sonnenscheindauer ; Gemüse
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  • 17
    facet.materialart.
    Unknown
    In:  Zeitschrift
    Publication Date: 1950
    Description: Detailierte Berichte über das Auftreten von Schaderregern in der Landwirtschaft für jedes Jahr; Zusammenhänge zu Witterungsbedingungen werden zu Beginn der entsprechenden Hefte, sowie teilw. bei Besprechung der jeweiligen Schaderreger hergestellt KATASTER-BESCHREIBUNG: KATASTER-DETAIL:
    Keywords: Westdeutschland, regional aufgelöst ; 1950-2008 ; Pflanzenkrankheit ; Pflanzenschädling
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  • 18
    Publication Date: 1950
    Description: Beobachtungen zum Auftreten von Roggengallmücke, Halmfliege, Getreidehalmwespe, Hafermilbe und Zwergzikade unter bestimmten Witterungsbedingungen (warme und trockene Sommer und Herbste) KATASTER-BESCHREIBUNG: Einfluss der Witterung (Temperatur und Niederschlag) im Sommer und Herbst auf das Auftreten der Getreideschädlinge KATASTER-DETAIL: Delta T (Sommer und Herbst) + und Delta Nied (Sommer und Hebrst) -, dann Auftreten +; Trockenperioden über mindestens 2 Jahre, dann Massenauftreten
    Keywords: Bayern ; 1947-1950 ; Anbautermine ; Landwirtschaft ; Niederschlag ; Pflanzenschädling ; Roggen ; Temperatur ; Trockenheit ; Weizen ; Witterung
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  • 19
    Publication Date: 2019-06-28
    Description: A literature survey was conducted to determine the relation between aircraft ignition sources and inflammables. Available literature applicable to the problem of aircraft fire hazards is analyzed and, discussed herein. Data pertaining to the effect of many variables on ignition temperatures, minimum ignition pressures, and minimum spark-ignition energies of inflammables, quenching distances of electrode configurations, and size of openings incapable of flame propagation are presented and discussed. The ignition temperatures and the limits of inflammability of gasoline in air in different test environments, and the minimum ignition pressure and the minimum size of openings for flame propagation of gasoline - air mixtures are included. Inerting of gasoline - air mixtures is discussed.
    Keywords: Aircraft Propulsion and Power
    Type: NACA-TN-2227
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  • 20
    Publication Date: 2019-06-28
    Description: As part of a general investigation of propellers at high forward speeds, tests of two 2-blade propellers having the NACA 4-(3)(8)-03 and NACA 4-(3)(8)-45 blade designs have been 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 0.725 to establish in detail the changes in propeller characteristics due to compressibility effects. These propellers differed primarily only in blade solidity, one propeller having 50 percent and more solidity than the other. Serious losses in propeller efficiency were found as the propeller tip Mach number exceeded 0.91, irrespective of forward speed or blade angle. The magnitude of the efficiency losses varied from 9 percent to 22 percent per 0.1 increase in tip Mach number above the critical value. The range of advance ratio for peak efficiency decreased markedly with increase of forward speed. The general form of the changes in thrust and power coefficients was found to be similar to the changes in airfoil lift coefficient with changes in Mach number. Efficiency losses due to compressibility effects decreased with increase of blade width. The results indicated that the high level of propeller efficiency obtained at low speeds could be maintained to forward sea-level speeds exceeding 500 miles per hour.
    Keywords: Aircraft Propulsion and Power
    Type: NACA-TR-999
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  • 21
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    In:  CASI
    Publication Date: 2019-06-28
    Description: An investigation has been made to explore the possibilities of axial-flow compressors operating with supersonic velocities into the blade rows. Preliminary calculations showed that very high pressure ratios across a stage, together with somewhat increased mass flows, were apparently possible with compressors which decelerated air through the speed of sound in their blading. The first phase of the investigation was the development of efficient supersonic diffusers to decelerate air through the speed of sound. The present report is largely a general discussion of some of the essential aerodynamics of single-stage supersonic axial-flow compressors. As an approach to the study of supersonic compressors, three possible velocity diagrams are discussed briefly. Because of the encouraging results of this study, an experimental single-stage supersonic compressor has been constructed and tested in Freon-12. In this compressor, air decelerates through the speed of sound in the rotor blading and enters the stators at subsonic speeds. A pressure ratio of about 1.8 at an efficiency of about 80 percent has been obtained.
    Keywords: Aircraft Propulsion and Power
    Type: NACA-TR-974 , NACA-ACR-L6D02 , NACA-AR-36
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  • 22
    Publication Date: 2019-08-16
    Description: Contents: Preliminary notes on the efficiency of propulsion systems; Part I: Propulsion systems with direct axial reaction rockets and rockets with thrust augmentation; Part II: Helicoidal reaction propulsion systems; Appendix I: Steady flow of viscous gases; Appendix II: On the theory of viscous fluids in nozzles; and Appendix III: On the thrusts augmenters, and particularly of gas augmenters
    Keywords: Aircraft Propulsion and Power
    Type: NACA-TM-1259
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  • 23
    Publication Date: 2019-07-11
    Description: An investigation was conducted to determine the effects of water injection on the over-all performance of a modified J33-A-27 turbojet-engine compressor at the design equivalent speed of 11,800 rpm. The water-air ratio by weight was 0.05. With water injection the peak pressure ratio increased 9.0 per- cent, the maximum efficiency decreased 15 percent (actual numerical difference 0.12), and. the maximum total weight flow increased 9.3 percent.
    Keywords: Aircraft Propulsion and Power
    Type: NACA-RM-SE50F14
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  • 24
    Publication Date: 2019-07-11
    Description: The compressor from the XT-46 turbine-propeller engine was revised by removing the last two rows of stator blades and by eliminating the interstage leakage paths described in a previous report. With the revised compressor, the flow choking point shifted upstream into the last rotor-blade row but the maximum weight flow was not increased over that of the original compressor. The flow range of the revised compressor was reduced to about two-thirds that obtained with the original compressor. The later stages of the compressor did not produce the design static-pressure increase probably because of excessive boundary-layer build-up in this region. Measurements obtained in the ninth-stage stator showed that the performance up to this station was promising but that the last three stages of the compressor were limiting the useful operating range of the preceding stages. Some modifications in flow-passage geometry and blade settings are believed to be necessary, however, before any major improvements in over-all compressor performance can be obtained.
    Keywords: Aircraft Propulsion and Power
    Type: NACA-RM-SE50J10
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  • 25
    Publication Date: 2019-07-11
    Description: The power plant from a Mark 25 aerial torpedo was investigated both as a two-stage turbine and as a single-stage modified turbine to determine the effect on overall performance of nozzle size and shape, first-stage rotor-blade configuration, and axial nozzle-rotor running clearance. Performance was evaluated in terms of brake, rotor, and blade efficiencies. All the performance data were obtained for inlet total to outlet static pressure ratios of 8, 15 (design), and 20 with inlet conditions maintained constant at 95 pounds per square inch gage and 1000 F for rotor speeds from approximately 6000 to 18,000 rpm.
    Keywords: Aircraft Propulsion and Power
    Type: NACA-RM-SE50D12
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  • 26
    Publication Date: 2019-07-11
    Description: Performance data obtained with recording oscillographs are presented to show the transient response of the General Electric Integrated Electronic Control operating on the J47 RXl-3 turbo-Jet engine over a range of altitudes from 10,000 to 45,000 feet and at ram pressure ratios of 1.03 and 1.4. These data represent the performance of the final control configuration developed after an investigation of the engine transient behavior in the NACA altitude wind tunnel. Oscillograph traces of controlled accelerations (throttle bursts),oontrolled decelerations (throttle chops), and controlled altitude starts are presented.
    Keywords: Aircraft Propulsion and Power
    Type: NACA-RM-SE50G12
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  • 27
    Publication Date: 2019-07-11
    Description: A modified J33-A-27 compressor was operated over a range of equivalent impeller speeds from 6100 to 13,250 rpm in order to obtain the over-all compressor performance. At the equivalent design speed of 11,800 rpm, the maximum efficiency of 0.764 and peak pressure ratio of 4.56 occurred at an equivalent weight flow of 104.07 pounds per second. At the highest equivalent speed (13,250 rpm) a maximum efficiency of 0.711, a maximum equivalent weight flow of 123.00 pounds per second, and a peak pressure ratio of 5.76 were obtained.
    Keywords: Aircraft Propulsion and Power
    Type: NACA-RM-SE50D25
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  • 28
    Publication Date: 2019-07-12
    Description: An investigation is being conducted to determine the performance of the 12-stage axial-flow compressor of the XT-46 turbine-propeller engine. This compressor was designed to produce a pressure ratio of 9 at an adiabatic efficiency of 0.86. The design pressure ratios per stage were considerably greater than any employed in current aircraft gas-turbine engines using this type of compressor. The compressor performance was evaluated at two stations. The station near the entrance section of the combustors indicated a peak pressure ratio of 6.3 at an adiabatic efficiency of 0.63 for a corrected weight flow of 23.1 pounds per second. The other, located one blade-chord downstream of the last stator row, indicated a peak pressure ratio of 6.97 at an adiabatic efficiency of 0.81 for a corrected weight flow of 30.4 pounds per second. The difference in performance obtained at the two stations is attributed to shock waves in the vicinity of the last stator row. These shock waves and the accompanying flow choking, together with interstage circulatory flows, shift the compressor operating curves into the region where surge would normally occur. The inability of the compressor to meet design pressure ratio is probably due to boundary-layer buildup in the last stages, which cause axial velocities greater than design values that, in turn, adversely affect the angles of attack and turning angles in these blade rows.
    Keywords: Aircraft Propulsion and Power
    Type: NACA-RM-SE50E22
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