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  • 1
    facet.materialart.
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    In:  Anz. Schädl.kunde 20: 16ff
    Publication Date: 1944
    Description: Beziehung zwischen Klima und Insektenbiologie KATASTER-BESCHREIBUNG: KATASTER-DETAIL:
    Keywords: Deutschland, teilw. einzelne Regionen ; 1936-1941 ; Insekten ; Luftfeuchte ; Forst ; Klima ; Niederschlag ; Pflanzenschädling ; Temperatur
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  • 2
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    In:  Tharandter forst. Jahrb. 93: 681-687
    Publication Date: 1942
    Description: Auswertung der in Sachsen durchgeführten Anlockversuche und des Abfaltens über die Biologie der Nonne KATASTER-BESCHREIBUNG: Verschiebung der Hauptflugzeit des Falters, Unterschiede um bis 10-20 Tage feststellbar KATASTER-DETAIL:
    Keywords: Sachsen ; 1937-1942 ; Insekten ; Forst ; Pflanzenschädling
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  • 3
    Publication Date: 1943
    Description: Zusammenhang zwischen dem vermehrten Auftreten des Bergkieferenkäfers (Dendroctonus ponderosae) und den Witterungsbedingungen KATASTER-BESCHREIBUNG: Änderung des Niederschlages und damit einhergehendes vermindertes Wachstum hat in vielen Jahren den Befall mit Dendroctonus ponderosae und Epidemien gefördert, jedoch sind auch starke Befallsjahre in Jahren mit guter Niederschlagsverteilung mit geringerer Häufigkeit vorgekommen KATASTER-DETAIL:
    Keywords: Amerika ; 1932-39 ; Fichte ; Forst ; Pflanzenschädling ; Wachstum
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  • 4
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    In:  Mitt. Biol. Reichsanst. H. 63: 46-48
    Publication Date: 1941
    Description: Beschreibungen zum Gesundheitszustand einer Population von Nonnen, ihrer Lebens- und Vermehrungsfähigkeit im Zusammenhang mit dem Massenauftreten, aber auch dem Zusammenbrechen der Population KATASTER-BESCHREIBUNG: Verringerung der Populationssichte durch Räuber kann bei 95% liegen KATASTER-DETAIL:
    Keywords: Deutschland ; 1900-1940 ; Insekten ; Forst ; Pflanzenschädling
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  • 5
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    In:  Forstwiss. Centralbl. Thar. forstl. Jahrb. 66: 115-120
    Publication Date: 1944
    Description: Beschreibung des Ertragsrückgang und der Schäden durch die Spätfröste im Mai 1943 KATASTER-BESCHREIBUNG: Spätfröste verursachten Schäden an Kiefern, Maitriebbildung teilweise extrem gestört und Posthorn- oder kandelaberartige Triebbildung als Folge des Frostes, unterschiedliche Empfindlichkeit der Baumarten KATASTER-DETAIL: Delta T -, (Ende Mai 〈 -6°C), dann schwere Schäden an Walnuss, Eiche, Robinie, Roteiche, Esche, Tanne, mittlere Schiiden:Buche, Roterle, Ahorn, Fichte, Douglasie, Lärche; geringe Schiiden: Roflkastanie,Hainbuche, Linde, Weisserle, Ulme, Birke. Im allgemeinen blieben ohne Schäden: Aspe, Eberesche, Traubenkirsche, Kiefer, Strobe und Bankskiefer.
    Keywords: Nordostdeutschland ; 1943 ; Buche ; Eiche ; Ertrag ; Fichte ; Forst ; Kiefer ; Roterle ; Frost ; Ulme ; Rosskastanie
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  • 6
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    In:  Dtsch. Forstztg. 10: 307-308
    Publication Date: 1941
    Description: Beschreibung der großen Frassschäden der letzten Jahrzehnte, bezug der Temperatur und des Niederschlages auf die Entwicklungsmöglichkeit einer Population KATASTER-BESCHREIBUNG: Ziiterte Untersuchungen zur Entwicklung der Nonnenraupe KATASTER-DETAIL: Delta T+ (Temperaturoptimum von 21.5°C, Ende April-Anfang Mai), dann günstige Entwiclungsbedingungen Delta Nied- (relative Feuchte schwankt zwischen 50-100%), dann Absterben großer Zahl futtersuchender Raupen
    Keywords: Deutschland, teilw. einzelne Regionen ; 1850-1940 ; Insekten ; Luftfeuchte ; Fichte ; Forst ; Kiefer ; Niederschlag ; Pflanzenschädling ; Temperatur
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  • 7
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    In:  Ann. Ent. fenn. 8: 49-71
    Publication Date: 1942
    Description: Schadinsekten und Pilze der Espe, Beschreibung und Beziehung verschiedener Insekten und Pilze an dem Vertrockungsprozess KATASTER-BESCHREIBUNG: KATASTER-DETAIL:
    Keywords: Finnland ; 1939-1940 ; Insekten ; Forst ; Pflanzenschädling
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  • 8
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    In:  Ann. Ent. fenn., Helsinki, 8: 143-163
    Publication Date: 1942
    Description: Vertrockungnung der Eberesche, der Salweide durch den Befall mit Kleinschmetterlingen, bzw. Käfern und sekundär Pilzen, Bescchreibung der Prozesse und Auswirkungen KATASTER-BESCHREIBUNG: KATASTER-DETAIL:
    Keywords: Finnland ; 1939-40 ; Insekten ; Forst ; Pflanzenkrankheit ; Pflanzenschädling
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  • 9
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    In:  Mitt. Forstwirtsch. u. -wissensch. 12: 25-68
    Publication Date: 1941
    Description: Auswertung verschiedener Parameter (Nonnenraupen, Falterflug) in unterschiedlichen Überwachungsbereichen der Forstentomologischen Dienststellen, Befallsermittlungsverfahren nach der Wellensteinschen Methode KATASTER-BESCHREIBUNG: Rhytmische Schwankungen der plötzlichen Übervermehrung, 10 oder 12 jährige Perioden, Bezug zu Schwankungen der Umweltbedingungen KATASTER-DETAIL:
    Keywords: Nord- und Mitteldeutschland ; 1939-40 ; Insekten ; Fichte ; Forst ; Kiefer ; Pflanzenschädling
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  • 10
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    In:  Ztschr. angew. Ent. 28: 357-365
    Publication Date: 1941
    Description: Vertrocknungsprozess der Espe, Beschreibung und Beziehung verschiedener Insekten und Pilze an diesem Prozess KATASTER-BESCHREIBUNG: KATASTER-DETAIL:
    Keywords: Finnland ; 1936-1941 ; Insekten ; Forst ; Pflanzenschädling
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  • 11
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    In:  Anz. Schädl.kunde 20: 13-16
    Publication Date: 1944
    Description: Beschreibung zum Befall von kanadischen Pappeln mit dem Prachtkäfer KATASTER-BESCHREIBUNG: KATASTER-DETAIL:
    Keywords: Rheinland-Pfalz ; 1934-1943 ; Insekten ; Forst ; Pflanzenschädling
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  • 12
    Publication Date: 1958
    Description: Auswertung aus 25jährigen Stammscheiben ermöglichen lagebedingte Darstellung von Ertragsunterschieden bei Fichte, Kiefer, weniger bei Buchen, Einfluss der Temperatur, des Niederschlages und der Höhe auf den Zuwachs KATASTER-BESCHREIBUNG: Der Zusammenhang von Niederschlag (Mai-August) und Temperatur (Mai-August) zum jährlichen Durchmesserwachstum ermöglich die Berechnung von Korrelations- und Regressionskoeffizienten, echte Beziehung in den unteren (〈400m) Höhenlagen, teilweise gesicherte Beziehungen in den mittleren (400-700m) Höhenlagen KATASTER-DETAIL: Delta Nied+ (Fichten in Eisenach): x=261+77.5(y-2.7) mit x=jährlicher Durchmesserzuwachs in mm, y=Niederschlagssumme Mai-August;
    Keywords: Thüringen ; letzten100 Jahre ; Buche ; Fichte ; Forst ; Kiefer ; Niederschlag ; Temperatur ; Vegetationsperiode ; Waldwachstum
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  • 13
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    In:  Kl. Mitt. Ver. Wasser-, Boden-, Lufthyg. 18: 125-130
    Publication Date: 1942
    Description: Bedeutung des Windes für den Wuchs, die Wasserversorgung und die Verbreitung des Samens und der Früchte von Pflanzen KATASTER-BESCHREIBUNG: Zusammenhang zwischen dem Wind und der mechanischen Schädigung von Blättern der Roßkastanie KATASTER-DETAIL: Wind +, dann Schädigung der Roßkastatienblätter +
    Keywords: Deutschland ; letzten 1000 Jahre ; Forst ; Wind
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  • 14
    Publication Date: 1958
    Description: Der Autor beschreibt den Einfluß von Feuchtigkeit und Temperatur im Boden und der Luft auf verschiedene Entwicklungsabschnitte der Maulwurfsgrille. Neben beschreibenden Beobachtungen im Feld wurden auch Kardinalwerte im Labor erhoben. Die Optimaltemperatur liegt bei ausreichender Feuchtigkeit bei 25-35°C. Das Entwicklungsmaximum liegt bei rel.Luftfeuchte 95-100% bei ca.43°C. Das Entwicklungsminimum liegt bei 0°C Bodentemperatur, wobei die Lufttemperatur niedriger sein kann, da sich die Insekten dann in den Boden zurückziehen. Die Haupteinflußfaktoren auf die Entwicklung bzw. das Überleben der Maulwurfsgrille sind Kannibalismus, Temperatur, Feuchtigkeit und Feinde. Diese modifizieren das Schlupfergebnis von 50-60% bis zu 95-100%. Ein Vergleich zwischen Bedingungen in Brandenburg und Südeuropa wird gezogen. KATASTER-BESCHREIBUNG: Einfluß von Feuchte und Temperatur auf den Entwicklungszyklus im Allgemeinen und die Eizeit im Speziellen. KATASTER-DETAIL: Die Eizeit schwankt zwischen 2-4 Wochen, kann aber bei hoher Luftfeuchtigkeit und einer Bodentemperatur von 22-28°C (Lufttemp.30°C) auf 10 Tage sinken. Bei spät gelegten Eiern (Ende Sept.-Okt.), hoher Bodenfeuchte und Bodentemp. 15-17°C steigt die Eizeit auf 5-6 Wochen. Je wärmer der Sommer und je milder der Winter, desto kürzer ist der Entwicklungszyklus (bei günstigen Bedingungen 1 Jahr, bei schlechteren 2 Jahre).
    Keywords: Brandenburg ; Tabak ; Forst ; Getreide ; Landwirtschaft ; Pflanzenschädling ; Hackfrüchte ; Obst ; Zierpflanzen ; Gemüse
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  • 15
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    In:  Nachrichtenblatt für den deutschen Pflanzenschutzdienst 12, Heft 2; p.21-35
    Publication Date: 1958
    Description: Es wird eine Übersicht auf die Maikäferflüge der Jahre 1950-1957 in der DDR auf Bezirks- und Kreisebene gegeben. Diese Ergebnisse werden versucht zusammen mit älteren Daten über den Maikäferflug seit 1920 (teilweise wird Literatur erwähnt, die den Maikäferflug an einigen Standorten seit ca.1830 enthält) mit Temperaturwerten in Verbindung zu setzen, um die Periodizität des Maikäferfluges zu erklären. KATASTER-BESCHREIBUNG: Regel zum Einfluß der Temperatur auf die Entwicklungslänge von Melolontha melolontha L.. KATASTER-DETAIL: In Gebieten mit 4jährigem Entwicklungszyklus kann dieser verkürzt werden, wenn das langjährige mittlere Jahresmaximum der Temperatur von 12,6°C überschritten wird.
    Keywords: DDR ; 1950-1957 ; Forst ; Pflanzenschädling
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  • 16
    Publication Date: 2019-08-24
    Description: The strength of representative types of flush-riveted joints has been determined by testing 865 single-shearing, double-shearing, and tensile specimens representing 7 types of rivet and 18 types of joint. The results, presented in graphic form, show the stress at failure, type of failure, and d/t ratio. In general, 'dimpled' joints were appreciably stronger than countersunk or protruding-head joints, but their strength was greatly influenced by constructional details. The optimum d/t ratios have been determined for the several kinds of joints. Photomacrographs of each type show constructional details and, in several instances, cracks in the sheet.
    Keywords: Mechanical Engineering
    Type: NACA-SR-142
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  • 17
    Publication Date: 2019-07-11
    Description: In the present paper an investigation is made of two stages of a multistage turboblower having a vaneless diffuser behind the impeller and guide vanes at the inlet to the nest stage. The method employed was that of investigating the performance of the successive elements of the blower (the impeller, vaneless diffuser, ets.) whereby the kinematics of the flow through the blower could be followed and the pressure at the different points computed. The character of the flow and the physical significance of the loss coefficients could thereby be determined so as to secure the best agreement of the computed with the actual performance of the blower. Since the tests were carried out for various delivery volumes, the dependence of the coefficients on a number of factors (angle of attack, velocities, etc.) could be obtained. The distribution of the losses that occur during the transformation of dynamic pressure at the impeller exit into static pressure could be found and likewise the range within which the friction coefficient varies in the vaneless diffuser. With the aid of factors having a certain physical significance, the centrifugal blower could be computed on the basis of a more or less schematical consideration of the phenomena occuring during the air flow through it, and the use of arbitrary factors and recourse to the geometrical similtude law thus avoided. The present investigation largely summarizes all the previous work af the CHI Blower Section on the different elements of a centrifugal blower. Some considerations on the analysis of model test data for application to full-scale are presented in the appendix.
    Keywords: Mechanical Engineering
    Type: NACA-TM-1043 , Report of the Central Aero-Hydrodynamical Institute, Moscow; Rept-191
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  • 18
    Publication Date: 2019-07-12
    Description: Four strut-supported, transpiration-cooled turbine blades were investigated experimentally in a turbojet engine. The blade shells were fabricated by the mold-sintering method with spherical stainless-steel powder. Two blades were investigated in order to evolve suitable capping methods for the blade tip. Two other blades were used to evaluate the durability of the porous-shell material. The blades were investigated at a turbine-tip speed of 1305 feet per second, an average turbine-inlet temperature of about 1670 F, and at a porous-shell temperature limited to a maximum of approximately 1040 F.
    Keywords: Mechanical Engineering
    Type: NACA-RM-SE57K25
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  • 19
    Publication Date: 2019-08-15
    Description: The results of measurements of the maximum friction available in braking on various runway surfaces under various conditions is shown for a C-123B airplane and comparisons of measurements with a tire-friction cart on the same runways are made. The.results of studies of wet-surface friction made with a 12-inch-diameter low-pressure tire on a tire-friction treadmill, with an automobile tire on the tire-friction cart, and with a 44 x 13 extra-high-pressure type VII aircraft tire at the Langley landing-loads track are compared. Preliminary results of tests on the tire-friction treadmill under wet-surface conditions to determine the effect of the wiping action of the front wheel of a tandem-wheel arrangement on the friction available in braking for the rear wheel are given.
    Keywords: Mechanical Engineering
    Type: NASA-MEMO-2-23-59L
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  • 20
    Publication Date: 2019-08-15
    Description: An investigation was conducted to obtain information on the tire-to-surface friction coefficients available in aircraft braking during the landing run. The tests were made with a C-123B airplane on both wet and dry concrete and bituminous pavements and on snow-covered and ice surfaces at speeds from 12 to 115 knots. Measurements were made of the maximum (incipient skidding) friction coefficient, the full-skidding (locked wheel) friction coefficient, and the wheel slip ratio during braking.
    Keywords: Mechanical Engineering
    Type: NASA-TR-R-20
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  • 21
    Publication Date: 2019-07-13
    Description: The changes produced on metallic surfaces as a result of grinding and polishing are not as yet fully understood. Undoubtedly there is some more or less marked change in the crystal structure, at least, in the top layer. Hereby a diffusion of separated crystal particles may be involved, or, on plastic material, the formation of a layer in greatly deformed state, with possible recrystallization in certain conditions. Czochralski verified the existence of such a layer on tin micro-sections by successive observations of the texture after repeated etching; while Thomassen established, roentgenographically by means of the Debye-Scherrer method, the existence of diffused crystal fractions on the surface of ground and polished tin bars, which he had already observed after turning (on the lathe). (Thickness of this layer - 0.07 mm). Whether this layer borders direct on the undamaged base material or whether deformed intermediate layers form the transition, nothing is known. One observation ty Sachs and Shoji simply states that after the turning of an alpha-brass crystal the disturbance starting from the surface, penetrates fairly deep (approx. 1 mm) into the crystal (proof by recrystallization at 750 C).
    Keywords: Mechanical Engineering
    Type: NACA-TM-1072 , Naturwissenschaften; 20; 22/24; 416-419
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  • 22
    Publication Date: 2019-07-13
    Description: Hardy's statement that the frictional force is largely adhesion, and to a lesser extent, deformation energy is proved by a simple experiment. The actual contact surface of sliding contacts and hence the friction per unit of contact surface was determined in several cases. It was found for contacts in normal atmosphere to be about one-third t-one-half as high as the macroscopic tearing strength of the softest contact link, while contacts annealed in vacuum and then tested, disclosed frictional forces which are greater than the macroscopic strength.
    Keywords: Mechanical Engineering
    Type: NACA-TM-1074 , Wissenschaftliche Veroeffentlichungen aus den Siemens-Werken; 17; 4; 38-42
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  • 23
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    In:  CASI
    Publication Date: 2019-07-13
    Description: In internal combustion engines, steam engines, air compressors, and so forth, the piston ring plays an important role. Especially, the recent development of Diesel engines which require a high compression pressure for their working, makes, nowadays, the packing action of the piston ring far more important than ever. Though a number of papers have been published in regard to researches on the problem of the piston ring, none has yet dealt with an exact measurement of pressure exerted on the cylinder wall at any given point of the ring. The only paper that can be traced on this subject so far is Mr. Nakagawa's report on the determination of the relative distribution of pressure on the cylinder wall, but the measuring method adopted therein appears to need further consideration. No exact idea has yet been obtained as to how the obturation of gas between the piston and cylinder, the frictional resistance of the piston, and the wear of the cylinder wall are affected by the intensity and the distribution of the radial pressure of the piston ring. Consequently, the author has endeavored, by employing an apparatus of his own invention, to get an exact determination of the pressure distribution of the piston ring. By means of a newly devised ring tester, to which piezoelectricity of quartz was applied, the distribution of the radial pressure of many sample rings on the market was accurately determined. Since many famous piston rings show very irregular pressure distribution, the author investigated and achieved a manufacturing process of the piston ring which will exert uniform pressure on the cylinder wall. Temperature effects on the configuration and on the mean spring power have also been studied. Further, the tests were performed to ascertain how the gas tightness of the piston ring may be affected by the number or spring power. The researches as to the frictional resistance between the piston ring and the cylinder wall were carried out, too. The procedure of study, and experiments conducted by the author, on this subject will be fully described in the following paragraphs.
    Keywords: Mechanical Engineering
    Type: NACA-TM-1057 , 32st Rep. of Okochi Res. Lab.: Scientific Papers of the Inst. of Physical and Chemical Research, Tokyo University; 10; 182; 107-185
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  • 24
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    In:  CASI
    Publication Date: 2019-07-13
    Description: The discovery and introduction of the internal combustion engine has resulted in a very rapid development in machines utilizing the action of a piston. Design has been limited by the internal components of the engine, which has been subjected to ever increasing thermal and mechanical stresses, Of these internal engine components, the piston and piston rings are of particular importance and the momentary position of engine development is not seldom dependent upon the development of both of the components, The piston ring is a well-known component and has been used in its present shape in the steam engine of the last century, Corresponding to its importance, the piston ring has been a rich field for creative activity and it is noteworthy that in spite of this the ring has maintained its shape through the many years. From the many and complicated designs which have been suggested as a packing between piston and cylinder wall hardly one suggestion has remained which does not resemble the original design of cast iron rectangular ring.
    Keywords: Mechanical Engineering
    Type: NACA-TM-1056 , ATZ Automobiltechnische Zeitschrift; 45; 3; 62-67
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  • 25
    Publication Date: 2019-07-11
    Description: The exact mathematical treatment of the problem is possible by replacing the propeller blade by a homogeneous prismatic rod. Conclusions can them be drawn as to the behavior of an actual propeller, since tests on propeller blades have indicated a qualitative agreement with the homogeneous rod. The natural frequencies are determined and the stressing of the systems under the various vibration modes are discussed.
    Keywords: Mechanical Engineering
    Type: NACA-TM-1051 , Jahrbuch 1938 der Deutschen Luftfahrtforschung; 141-159
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  • 26
    Publication Date: 2019-08-15
    Description: The concept of the adhesive power of a tire with respect to the road involves several properties which result from the purpose of the tire; namely, connecting link between vehicle and road: (1) The tire must transfer the tractive and braking forces acting in the direction of travel (tractive and braking adhesion); (2) The tire is to prevent lateral deviations of the vehicle from the desired direction of travel (track adhesion). Moreover, the rubber tire provides part of the springing of the vehicle. Above all, it has to level out the minor road irregularities; thus it smoothes, as it were, the road and simultaneously reduces the noise of driving. The springing properties of the tire affect the adhesive power. The tests described below comprise a determination of the braking and track adhesion of individual tires. The adhesion of driven wheels has not been investigated so far.
    Keywords: Mechanical Engineering
    Type: NACA-TM-1416 , Versuche zur Feststellung des Haftvermogens von Personenwagen-Bereifungen; Nr. 22
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  • 27
    Publication Date: 2019-08-15
    Description: The low-speed (up to 4 miles per hour) yawed-rolling characteristics of two 56 x 16 32-ply-rating, type 7 aircraft tires under straight-yawed rolling were determined over a range of inflation pressures and yaw angles for a vertical load approximately equal to 75 percent of the rated vertical load. The quantities measured or determined included cornering force, drag force self-alining torque, pneumatic caster vertical tire deflection, yaw angle, and relaxation length. During straight-yawed rolling the normal force generally increased with increasing yaw angle within the test range. The self-alining torque increased to a maximum value and then decreased with increasing angle of yaw. The pneumatic caster tended to decrease with increasing yaw angle.
    Keywords: Mechanical Engineering
    Type: NASA-MEMO-2-7-59L , L-171
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  • 28
    Publication Date: 2019-08-15
    Description: Preliminary data are presented covering the performance of a low-speed, five-cylinder piston pump designed for handling boiling hydrogen. This pump was designed for a flow of 55 gallons per minute at 240 rpm with a discharge pressure of 135 pounds per square inch. Tests were made using JP-4 fuel, liquid nitrogen, and liquid hydrogen. Pump delivery and endurance characteristics were satisfactory for the range of operation covered. In connection with the foregoing pump development, the cavitation characteristics of a preliminary visual model, glass-cylinder pump and of a simple reciprocating disk were studied. Subcooling of approximately 0.60 F was obtained from the cavitation produced by reciprocating a disk in boiling nitrogen and in boiling water. The subcooling obtained in a similar manner with liquid hydrogen was somewhat less.
    Keywords: Mechanical Engineering
    Type: NASA-MEMO-3-6-59E , E-239
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  • 29
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    In:  Other Sources
    Publication Date: 2019-08-26
    Description: Externally pressurized gas-lubricated bearings with multiple orifice feed are investigated. An analytical treatment is developed for a semi-cylindrical bearing with 9 orifices and for a cylindrical journal bearing with 192 radial and 24 axial orifices. Experiments are described on models of the two bearing configurations with specially designed fixtures which incorporate pneumatic loading and means for determining pressure profiles, gas flow and gap height. The correlation between theory and experiment is satisfactory.
    Keywords: Mechanical Engineering
    Type: Report No. 30-14
    Format: text
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  • 30
    Publication Date: 2019-08-16
    Description: An experimental investigation was made at the Langley landing loads track to obtain data on the maximum spin-up coefficients of friction developed by a landing gear having a static-load rating of 20,000 pounds. The forward speeds ranged from 0 to approximately 180 feet per second and the sinking speeds, from 2.7 feet per second to 9.4 feet per second. The results indicated the variation of the maximum spin-up coefficient of friction with forward speed and vertical load. Data obtained during this investigation are also compared with some results previously obtained for nonrolling tires to show the effect of forward speed.
    Keywords: Mechanical Engineering
    Type: NASA-MEMO-12-20--58L , L-105
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  • 31
    Publication Date: 2019-08-15
    Description: An experimental investigation was made to evaluate the durability and permeability of a group of transpiration-cooled, strut-supported turbine blades. The porous shells were formed from a woven-wire material. The blades were fabricated by a contractor for the Bureau of Aeronautics. The results of permeability tests indicated that the shell material exhibited large random variations in local permeability, which result in excessive coolant flows and very nonuniform cooling. For this reason no heat-transfer evaluations were made because any results would have been inconclusive. Four blades were investigated for structural soundness in a turbo-jet engine operating at a turbine-inlet temperature of approximately 1670 deg F and a turbine tip speed of approximately 1305 feet per second. The maximum temperature of the porous-shell material was approximately 1050 deg F. Inspection of the first two blades after 10 minutes of engine operation revealed that the tips of both of the blades had failed. For the second pair of blades, an improved tip cap was provided by the use of built-up weld extending from strut tip to shell. One of these blades was then operated for 33 hours without failure, and was found to be in good condition at the end of this time. The second blade of this second pair failed within the first 10 minutes of operation because of a poor bond between shell and strut lands.
    Keywords: Mechanical Engineering
    Type: NASA-MEMO-1-29-59E
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