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Air-turbine-driven wire whip is clamped near spray-gun mount. When spray gun is installed, wire whip is in position to remove foam buildup from nozzle face. Two lengths of wire 1 to 2 inches long and about 0.03 inch in thickness are used. Foam spray would be prevented from accumulating on nozzle face by increasing purge flow and cutting vortex-generating grooves inside cap and on nozzle flats.
Splattered metal produced by welding can be easily removed from inaccessible areas by method resembling ball milling. Hard steel balls are vibrated inside welded unit so that they "scrub away" excess metal on interior side of weld joint.
Two basic inlet concepts, a high throat Mach number (0.79) design and a low throat Mach number (0.60) design, were tested with four diffuser acoustical treatment designs that had face sheet porosity ranging from 0 to 24 percent for the high Mach number inlet and 0 to 28 percent for the low Mach number inlet. The tests were conducted in a low speed wind tunnel at free stream velocities of 0, 41, and 62 m/sec and angles of attack to 50 deg. Inlet throat Mach number was varied about the design value. Increasing the inlet diffuser face sheet porosity resulted in an increase in total pressure loss in the boundary layer for both the high and low Mach number inlet designs, however, the overall effect on inlet total pressure recovery of 0.991 at the design throat Mach number, a free stream velocity of 41 m/sec, and an angle of attack of 50 deg; Inlet flow separation at an angle of attack of 50 deg was encountered with only one inlet configuration the high Mach number design with the highest diffuser face sheet porosity (24 percent).
This report describes the design configuration and method used to design the forced engine exhaust to bypass air mixing system for Lycoming's QCGAT engine. This mixer is an integral part of the total engine and nacelle system and was configured to reduce the propulsion system noise and fuel consumption levels.
Tests were run both in forward and in reverse thrust modes with a bellmouth inlet, five accelerating inlets (one hard wall and four treated) with a design throat Mach number of 0.79 at the takeoff condition, and four low Mach inlets (one hard wall and three treated) with a design throat Mach number of 0.6 at the takeoff condition. Unsuppressed and suppressed inlet radiated noise levels were measured at conditions representative of QCSEE takeoff, approach, and reverse thrust operations. Measured aerodynamic performance of the accelerating inlet is also included. The test objectives, facility, configurations, are described as well as the data analysis, results, and comparisons.
The design was based on the LTS-101 engine family for the core engine. A high bypass fan design (BPR=9.4) was incorporated to provide reduced fuel consumption for the design mission. All acoustic and pollutant emissions goals were achieved. A discussion of the preliminary design of a business jet suitable for the developed propulsion system is included. It is concluded that large engine technology can be successfully applied to small turbofans, and noise or pollutant levels need not be constraints for the design of future small general aviation turbofan engines.
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The successful operation of an aircraft gas turbine combustion system incorporating a state-of-the-art catalytic reactor as the main stage, along with a conventional pilot stage for low power operation, is reported to have been achieved with high combustion efficiency at moderate engine pressure ratios. The extremely low nitrogen oxides emission level taken by the program as its goal has also been achieved. It is noted that significant improvements in the operating temperature capability of catalytic reactor materials will be required for the successful application of such devices to the very high pressure ratio, high temperature engines assumed to be the ultimate application of the devices studied.
Scraper removes silicon deposits from inner walls of reactor vessel. Scraper supported by gas bearing. Scraper made of non-contaminating material such as quartz or silicon.
A combustor program was conducted to evolve and to identify the technology needed for, and to establish the credibility of, using combustors with catalytic reactors in modern high-pressure-ratio aircraft turbine engines. Two selected catalytic combustor concepts were designed, fabricated, and evaluated. The combustors were sized for use in the NASA/General Electric Energy Efficient Engine (E3). One of the combustor designs was a basic parallel-staged double-annular combustor. The second design was also a parallel-staged combustor but employed reverse flow cannular catalytic reactors. Subcomponent tests of fuel injection systems and of catalytic reactors for use in the combustion system were also conducted. Very low-level pollutant emissions and excellent combustor performance were achieved. However, it was obvious from these tests that extensive development of fuel/air preparation systems and considerable advancement in the steady-state operating temperature capability of catalytic reactor materials will be required prior to the consideration of catalytic combustion systems for use in high-pressure-ratio aircraft turbine engines.
Anomalous behavior of the Earth Sensor Assemblies (ESA) had been observed on the Defense Meteorological Satellite Program (DMSP) 5D/1 satellites and the Tiros-N satellite. The present investigation is concerned with the reasons for the observed phenomena. Degradation of the Earth Radiation Budget (ERB) solar channels and the Solar Backscatter Ultraviolet and Total Ozone Mapping Spectrometer (SBUV/TOMS) diffuser plate is attributed to transmission or reflection loss originating from the growth of an organic film by photolytic polymerization. Simultaneous degradation of the ESA interference filter coated lenses facing the flight direction and the recovery of the ERB solar channels on Nimbus 6 and 7 is caused by a reaction with the increase in the exospheric atmospheric density caused by solar maximum.
Small particles are ideal for combined studies with surface analytical and electron microscopy/diffraction methods. In this way crystallography, microstructure, morphology, physical stability, and electronic structure can be correlated directly with chemical reactivity. Various integrated experimental approaches for conducting model studies with UHV-evaporated particles have been successfully developed; they entail the use of TPD, AES, XPS, and work function measurements on one hand and standard TEM/TED, in-situ TEM/TED, and in-situ STED/TEM techniques on the other hand. The essential features of four particular experimental approaches are discussed and a selection of representative results is presented to illustrate the potential usefulness of such studies in the field of catalysis.
Vacuum-chuck eliminates glass and sponge artwork support. Vacuum copyboard allows camera-ready original slid on top plate for proper positioning, then holds securely for photography. Bleed valve allows vacuum in copyboard box adjusted for small or large originals. With new copyboard, time-consuming and costly procedures unnecessary.
The penetration of gaseous nitrogen into liquid oxygen at a pressure of 150 psi was determined by monitoring the composition of the evaporating liquid in a nitrogen analyzer. For pressurization times of about 1 hr the penetration depth varies between 0.0024 and 0.018 in. at an evaporation rate of about 1 gal/day. These are small compared to the penetration depth of 22.2 in. measured in the 7-inch high temperature tunnel at a pressure of 1500 psi, pressurization time of 5 min, and evaporation rate of 121 gal/day.
Possible compounds for the 9.7 micron spectral feature and the 2175A spectral bump are examined. Results from electron microscopy and high resolution transmission electron microscopy are discussed.
Ignition wire repositioned to suppress unburned particles. In new configuration, ignition coil located near top of combustion chamber. As charge burns, unburned portion held at bottom of chamber. Little or no unburned charge ejected. Nearly uniform pressure generated, and only gases ejected from combustion chamber.
It is shown how helium-3 can be obtained from the moon and how its use in fusion reactors can benefit the inhabitants of this planet. The physics and technology issues associated with the use of He-3 is addressed. A description is given of He-3 distribution on the moon and of methods which could be used to retrieve it.
A simple microphysical cloud parcel model and a simple representation of the background marine aerosol are used to predict the concentrations and compositions of droplets of various sizes near cloud base. The aerosol consists of an externally-mixed ammonium bisulfate accumulation mode and a sea-salt coarse particle mode. The difference in diffusional growth rates between the small and large droplets as well as the differences in composition between the two aerosol modes result in substantial differences in solute concentration and composition with size of droplets in the parcel. The chemistry of individual droplets is not, in general, representative of the bulk (volume-weighted mean) cloud water sample. These differences, calculated to occur early in the parcel's lifetime, should have important consequences for chemical reactions such as aqueous phase sulfate production.