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Combustion instability in an acid-heptane rocket with a pressurized-gas propellant pumping system

Description: Report presenting results of experimental measurements of low-frequency combustion instability of a 300-pound-thrust acid-heptane rocket engine as compared with the trends predicted by an analysis of combustion instability in a rocket engine. Results regarding the chugging frequency, combustion time delay, effect of rocket combustion-chamber characteristic length, effect of throttling, effect of injection velocity, effect of oxidant-fuel ratio, variation of chugging frequency with amplitude of chamber pressure fluctuations, and evaluation of the analysis are provided.
Date: May 1953
Creator: Tischler, Adelbert O. & Bellman, Donald R.
Partner: UNT Libraries Government Documents Department

Some screeching-combustion characteristics of a transpiration-cooled afterburner having a porous wall of wire cloth

Description: Report presenting an investigation of the screeching characteristics of two flame-holder configurations in a full-scale transpiration-cooled afterburner. The investigation indicated that a porous wall of wire cloth may be effective in eliminating or reducing the tendency to screech in some high-performance afterburners, but further testing is required. Results regarding the diametrical V-gutter, single-ring V-gutter, and durability of wire cloth are provided.
Date: November 29, 1954
Creator: Koffel, William K.; Harp, James L., Jr. & Bryant, Lively
Partner: UNT Libraries Government Documents Department

An analytical study of turbulent and molecular mixing in rocket combustion

Description: From Introduction: "The many physical processes which occur simultaneously in rocket combustion make the entire process extremely complex (ref. 1). The combustion chamber length required for evaporation of liquid-propellant sprays has already been studied (refs. 2, 3, and 4)."
Date: September 1958
Creator: Bittker, David A.
Partner: UNT Libraries Government Documents Department

Analysis of spark-ignition engine knock as seen in photographs taken at 200,000 frames per second

Description: Report discussing a motion picture of the development of knock in a spark-ignition engine, which consists of 20 photographs taken at intervals of 5 microseconds, or at a rate of 200,000 photographs per second, with an equivalent wide-open exposure time of 6.4 microseconds for each photograph.
Date: 1946~
Creator: Miller, Cearcy D.; Olsen, H. Lowell; Logan, Walter O., Jr. & Osterstrom, Gordon E.
Partner: UNT Libraries Government Documents Department

Experimental Behavior of Pentaborane-Air Combustion Products During Expansion in a Convergent Divergent Nozzle

Description: In order to evaluate the post combustion behavior of boric oxide, pentaborane-air mixtures, burned to completion at a combustor pressure of 3 atmospheres, were expanded through a 7.1-inch-long convergent-divergent nozzle having a 4-inch-diameter throat and an exit-to-throat area ratio of 1.68. The experimentally determined thrust performance was in good agreement with the ideal equilibrium performance at stagnation temperatures of 3300 deg R and lower. The boric oxide vapor at the combustor exit required about 400 F deg supercooling before any condensed phase was observed. For a given thrust, fuel consumption was as much as 20 percent greater than predicted from vapor-pressure data for combustor outlet temperatures i n the vicinity of 3600 deg R. A similar result could be expected in full-scale engines, since the test combustor provided an unusually long dwell time and a highly turbulent environment. During the expansion process, the vapor (when present) did not condense to the extent predicted for an equilibrium expansion process. Moreover, condensation was observed only i n the form of small, abrupt phase changes i n the subsonic flow near the throat. Friction, due to liquid boric oxide films on the nozzle surfaces, was negligible when the surface temperature was above 800 F.
Date: February 18, 1958
Creator: Branstetter, J. R. & Setze, P. C.
Partner: UNT Libraries Government Documents Department

Tests of Run-of-Mine and Briquetted Coal in a Locomotive Boiler

Description: From Object of Tests: "The primary object of the tests was to study the relative performances of the two types of briquets and of the coal, with reference to efficiency, tendency to smoke, and the ease with which steam could be kept up, when each of the three varieties of fuel was burned at several rates of combustion. Many secondary objects were in mind, the data concerning which are discussed under "Effect of varying rates of combustion," pages 20-27."
Date: 1911
Creator: Ray, Walter T. & Kreisinger, Henry
Partner: UNT Libraries Government Documents Department

An Investigation of Powdered Coal as Fuel for Power-Plant Boilers: Tests at Oneida Street Power Station, Milwaukee, Wisconsin

Description: From Introduction: "This bulletin presents the results of 36 tests made on a 468-horse-power Edge Moor boiler fired with pulverized coal at the Oneida Street Station of the Milwaukee Electric Railway & Light Co., Milwaukee, Wis."
Date: 1923
Creator: Kreisinger, Henry; Blizard, John; Augustine, C. E. & Cross, B. J.
Partner: UNT Libraries Government Documents Department

Addition of heat to a compressible fluid in motion

Description: From Introduction: "The purpose of this report is to summarize, without extended proofs, the results of a study of a simplified model of nonadiabiatic, compressible fluid flow, both subsonic and supersonic, and to state these results in a form that will make them immediately useful in providing a theoretical background for current technical problems of high-speed combustion.
Date: February 1945
Creator: Hicks, Bruce L
Partner: UNT Libraries Government Documents Department

Effect of inlet-air parameters on combustion limit and flame length in 8-inch-diameter ram-jet combustion chamber

Description: Report presenting an investigation with a ram-jet combustion chamber to determine the effect of fuel-air ratio and the inlet-air parameters of pressure, temperature, and velocity on combustion limit, combustion efficiency, and flame length.
Date: July 22, 1948
Creator: Cervenka, A. J. & Miller, R. C.
Partner: UNT Libraries Government Documents Department

Development of Coal Combustion Sensitivity Tests for Smoke Detectors

Description: Standard smoldering and flaming combustion tests using small coal samples have been developed by the U.S. Bureau of Mines as a method to evaluate the response of a smoke detector. The tests are conducted using a standard smoke box designed and constructed according to Underwriters Laboratories. The tests provide a standard, easily reproducible smoke characteristic for smoldering and flaming coal combustion, based upon a comparison of the smoke optical density and the response of a standard ionization chamber to the smoke. With these standard tests, the range of threshold limits for the response of a smoke detector and the detector's reliability can be evaluated for nearly identical smoke visibility and smoke physical characteristics. The detector's threshold response limits and reliability need to be well defined prior to the instrument's use as part of a mine fire warning system for improved mine safety.
Date: 1995
Creator: Edwards, John C. & Morrow, Gerald S.
Partner: UNT Libraries Government Documents Department

Exploratory investigation of static- and base-pressure increases resulting from combustion of aluminum borohydride adjacent to body of revolution in supersonic wing tunnel

Description: Report presenting pressure distribution associated with the stable combustion of aluminum borohydride about a body of revolution in a wind tunnel at Mach number 2.47. Pressure increases on the cylindrical and base surfaces of the model were measured. Results regarding the burning and associated flow phenomena, axial and meridional static-pressure data obtained during combustion, and base-pressure data during combustion are provided.
Date: October 2, 1957
Creator: Serafini, John S.; Dorsch, Robert G. & Fletcher, Edward A.
Partner: UNT Libraries Government Documents Department

Variation of pressure limits of flame propagation with tube diameter for various isooctane-oxygen-nitrogen mixtures

Description: An investigation was made of the change in the pressure limits of flame propagation with tube diameter for various isooctane-oxygen-nitrogen mixtures. Pressure limits were measured in cylindrical glass tubes of four different inside diameters at six different oxygen-nitrogen ratios. Under the experimental conditions, flame propagation was found to be impossible in isooctane-oxygen mixtures with oxygen concentrations less than 11 to 12 percent. Critical tube diameters for flame propagation were calculated and the effect of pressure was determined and compared with the effect of pressure on quenching distance. Critical diameters were related to flame speeds for various isooctane-oxygen-nitrogen mixtures.
Date: March 3, 1952
Creator: Spakowski, Adolph E. & Belles, Frank E.
Partner: UNT Libraries Government Documents Department

Preliminary investigation of a ceramic lining for a combustion chamber for gas-turbine use

Description: Combustion chamber liners for gas turbines and experimental set-ups were tested for failure. A ceramic-lined test chamber was operated at fuel/air ratios up to 0.050. Thermal-shock evaluation indicated that a ceramic lining, which expands after firing, would crack but would not fall apart during operation. Refractoriness of the lining and the resistance to mechanical shock were adequate. In general, shell temperature reductions of approximately 400 deg F were effected by the use of this lining at fuel/air ratios of 0.016 and 0.050. The mechanism of failure of the ceramic lining was induced by sudden heating and cooling during operation.
Date: April 12, 1948
Creator: Woodward, William H. & Bobrowsky, A. R.
Partner: UNT Libraries Government Documents Department

Exploratory investigation of aerodynamic effects of external combustion of aluminum borohydride in airstream adjacent to flat plate in Mach 2.46 tunnel

Description: Report presenting pressure distributions associated with stable combustion of aluminum borohydride in the supersonic stream adjacent to a short, 13-inch chord, and an extended, 25-inch chord, flat-plate model. High-speed direct and schileren motion pictures of the flame and associated shock waves were taken. Results regarding the description of the combustion and associated stream disturbances, static-pressure change at model reference surface caused by combustion, lift forces resulting from combustion, base pressure change caused by combustion, stream-parameter measurements during combustion, and surface temperature changes during combustion are provided.
Date: July 29, 1957
Creator: Dorsch, Robert G.; Serafini, John S. & Fletcher, Edward A.
Partner: UNT Libraries Government Documents Department

A correlation of the effects of compression ratio and inlet-air temperature on the knock limits of aviation fuels in a CFR engine 1

Description: Report presenting a method of correlating the effects of compression ratio and inlet-air temperature on the knock limits of aviation fuels. Knock-limited performance tests of several fuels were run to check the method.
Date: May 1945
Creator: Evvard, John C. & Branstetter, J. Robert
Partner: UNT Libraries Government Documents Department