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Potential Flow in Engine Valves

Description: "The extensive applicability of the hydrodynamic theory to the problems of engine construction is clearly shown in the following attempt to determine by exact methods the nature of the flow in valves under variously restricted conditions. Observation shows that two principal kinds of flow occur in simple flat-seated valves. For small valve lifts, the flow is along the horizontal wall and is therefore deflected 90 degrees, but for greater valve lifts the flow separates and forms a free stream, whose angle of deflection naturally increases with increasing lift" (p. 1).
Date: December 1925
Creator: Eck, Bruno
Partner: UNT Libraries Government Documents Department

Ground Simulator Studies of the Effects of Valve Friction, Stick Friction, Flexibility, and Backlash on Power Control System Quality

Description: Note presenting tests on a power control system by means of a ground simulator to determine the effects of various combinations of valve friction and stick friction on the ability of the pilot to control the system. The results show that, when valve friction was present in a rigid system, the introduction of stick friction was beneficial in that it restored some of the quality lost because of the valve friction. Results regarding the rigid control system, flexible control system, and control system with backlash are provided.
Date: April 1957
Creator: Brown, B. Porter
Partner: UNT Libraries Government Documents Department

An Investigation of the Use of Discharge Valves and an Intake Control for Improving the Performance of N.A.C.A. Roots Type Supercharger

Description: "This report presents the results of an analytical investigation on the practicability of using mechanically operated discharge valves in conjunction with a manually operated intake control for improving the performance of N. A. C. A. Roots type superchargers. These valves, which may be either of the oscillating or rotating type, are placed in the discharge opening of the supercharger and are so shaped and synchronized with the supercharger impellers that they do not open until the air has been compressed to the delivery pressure. The intake control limits the quantity of air compressed to engine requirements by permitting the excess air to escape from the compression chamber before compression begins" (p. 479).
Date: June 29, 1928
Creator: Schey, Oscar W. & Wilson, Ernest E.
Partner: UNT Libraries Government Documents Department

The Valve-Actuated Pulse Column Design and Operation

Description: The following report describes a countercurrent extraction column, which employs timed solenoid valves and pressurized feeds to provide a pulsing action to disperse the phases. This report further describes the 4-stage cycle of the column operation.
Date: December 3, 1951
Creator: Burger, L. L.
Partner: UNT Libraries Government Documents Department

Steady- and intermittent-flow coefficients of poppet intake valves

Description: Report presenting flow coefficients of an intake valve, seat, and port combination were measured under steady- and intermittent-flow conditions. Tests were conducted at large and small pressure drops over an engine-speed range of 800 to 3600 rpm.
Date: March 1946
Creator: Stanitz, John D.; Lucia, Robert E. & Masselle, Francis L.
Partner: UNT Libraries Government Documents Department

A Large Bakeable Vacuum Valve

Description: This report describes the development and design of a large bakeable valve that is based on a unique seat arrangement and a novel motion seal.
Date: August 6, 1959
Creator: Batzer, Thomas H.
Partner: UNT Libraries Government Documents Department

Operating Temperatures of a Sodium-Cooled Exhaust Valve as Measured by a Thermocouple

Description: "A thermocouple was installed in the crown of a sodium-cooled exhaust valve. The valve was then tested in an air-cooled engine cylinder and valve temperatures under various engine operating conditions were determined. A temperature of 1337 F was observed at a fuel-air ratio of 0.064, a brake mean effective pressure of 179 pounds per square inch, and an engine speed of 2000 rpm" (p. 1).
Date: December 1943
Creator: Sanders, J. C.; Wilsted, H. D. & Mulcahy, B. A.
Partner: UNT Libraries Government Documents Department

The Design and Development of an Automatic Injection Valve With an Annular Orifice of Varying Area

Description: The purpose of this investigation was to provide an automatic injection valve of simple construction which would produce a finely atomized oil spray of broad cone angle and would fulfill the requirements of fuel injection in aircraft oil engines. The injection valve designed has only six parts - i. e., two concentric nozzle tubes flared at one end, two body parts, and two nuts. Analysis and engine tests indicate that the fuel spray from this type of injection valve has characteristics which reduce the time lag of autoignition and promote efficient combustion in high-speed oil engines.
Date: 1931
Creator: Joachim, William F.; Hicks, Chester W. & Foster, Hampton H.
Partner: UNT Libraries Government Documents Department

Air Flow Through Poppet Valves

Description: Report discusses the comparative continuous flow characteristics of single and double poppet valves. The experimental data presented affords a direct comparison of valves, single and in pairs of different sizes, tested in a cylinder designed in accordance with current practice in aviation engines.
Date: 1918
Creator: Lewis, G. W. & Nutting, E. M.
Partner: UNT Libraries Government Documents Department

Intermittent-flow coefficients of a poppet valve

Description: "Flow coefficients were determined for the inlet valve of a modern air-cooled cylinder during operation of the valve. The cylinder head with valves was mounted on a large tank that could be evacuated. Operating the valve with a rotating cam allowed air to flow through the valve into the evacuated tank. The change of pressure in the tank was a measure of the amount of air flowing though the valve in a given number of cycles. The flow coefficients were determined from the pressure across the valve, the quantity of air flowing, and the valve-lift curve" (p. 1).
Date: April 1939
Creator: Waldron, C. D.
Partner: UNT Libraries Government Documents Department

Effect of a low-loss air valve on performance of a 22-inch-diameter pulse-jet engine

Description: Report presenting the performance of a 22-inch-diameter pulse-jet engine using a net of low-loss modified air valves at ram pressures equivalent to simulated flight speeds. Results regarding combustion-air weight flow, flight thrust, maximum combustion-chamber pressure, specific fuel consumption, pressure cycle, and valve life are provided.
Date: June 1946
Creator: Bressman, Joseph R.
Partner: UNT Libraries Government Documents Department

HRT Process Flowsheets--Revised Edition

Description: Revised HRT flowsheets are presented. These revisions cover such items as relocation of freezer units on the lines, corrections to the numbering of lines, valves or instruments, and the addition of a few lines in the service areas. The waste and vent system flowsheet was redrawn as two sheets. (C.J.G.)
Date: December 15, 1959
Creator: Robertson, R. C. & Jones, J. E.
Partner: UNT Libraries Government Documents Department

Salt valve and instrumentation test using the nagle long shafted pump :final report.

Description: The Salt Valve and Instrumentation Test was done to provide data on equipment performance in high temperature environments similar to that expected in the next large scale application of that technology. The experiment tested three different valves: (1) a valve with the standard valve body and standard high temperature self-packing material; (2) a valve with the standard valve body and stainless steel O-rings; and (3) a magnetic valve that uses a high temperature coil and no packing material. The first valve, which was used at Solar Two, performed sufficiently throughout the test with only a small leak from the split-body, not the packing material, on the 6th day of testing on the long-term test. The second valve, with the stainless steel O-rings, developed a small leak on the last run of the third test at the bonnet (packing material), at which point it was noted to watch if it got worse and the test continued. By the 6th day of the long-term test, the leak was significant (up to 3 cups per day) and the test was terminated. The magnetic valve failed when exposed to a relatively low temperature of 500 F. According to the manufacturer, it was expected to survive up to temperatures of 600 F. Two different pressure transducers were tested and compared, Taylor and Dynisco. The Taylor pressure transducer was used and proven successful at Solar Two. However, they are no longer made. Therefore the experiment tested a new pressure transducer from Dynisco and compared the results to that of the Taylor. The Dynisco pressure transducer performed inaccurately from the beginning. The pressure transducer was affected by an increase in temperature when the pressure remained the same. Dynisco agreed to recalibrate the pressure transducer and/or send us a new one if the piece was faulty. However, in ...
Date: June 1, 2003
Creator: Welch, Kathleen T.
Partner: UNT Libraries Government Documents Department

Valve-Spring Surge

Description: Test equipment is described that includes a system of three quartz indicators whereby three different pressures could be synchronized and simultaneously recorded on a single oscillogram. This equipment was used to test the reliction of waves at ends of valve spring, the dynamical stress of the valve spring for a single lift of the valve, and measurement of the curve of the cam tested. Other tests included simultaneous recording of the stress at both ends of the spring, spring oscillation during a single lift as a function of speed, computation of amplitude of oscillation for a single lift by harmonic analysis, effect of cam profile, the setting up of resonance, and forced spring oscillation with damping.
Date: March 1937
Creator: Marti, Willy
Partner: UNT Libraries Government Documents Department

Whitey SCHe Ball Valves Provide Test Port Isolation

Description: These valves are 1/4-inch ball valves fabricated of 316 stainless steel. Packing is TFE (standard). They are used as normally closed isolation valves for test ports in the SCHe System between the gage root valve and the pressure indicator.
Date: October 19, 2000
Creator: Miska, C. R.
Partner: UNT Libraries Government Documents Department

The Processes in Spring-Loaded Injection Valves of Solid Injection Oil Engines

Description: "On the premise of a rectangular velocity wave arriving at the valve, the equation of motion of a spring-loaded valve stem is developed and analyzed. It is found that the stem oscillates, the oscillation frequency being consistently above the natural frequency of the nozzle stem alone, and whose amplitudes would increase in the absence of damping. The results are evaluated and verified on an example" (p. 1).
Date: November 1934
Creator: Lutz, O.
Partner: UNT Libraries Government Documents Department

The N.A.C.A. photographic apparatus for studying fuel sprays from oil engine injection valves and test results from several researches

Description: "Apparatus for recording photographically the start, growth, and cut-off of oil sprays from injection valves has been developed at the Langley Memorial Aeronautical Laboratory. The apparatus consists of a high-tension transformer by means of which a bank of condensers is charged to a high voltage. The controlled discharge of these condensers in sequence, at a rate of several thousand per second, produces electric sparks of sufficient intensity to illuminate the moving spray for photographing. The sprays are injected from various types of valves into a chamber containing gases at pressures up to 600 pounds per square inch" (p. 361).
Date: May 25, 1927
Creator: Beardsley, Edward G.
Partner: UNT Libraries Government Documents Department

Evaluation of an automatic inlet-pressure control valve for study of transient engine performance characteristics

Description: Report presenting an evaluation of data obtained with an automatic constant inlet-pressure control valve designed to facilitate the study of transient engine performance characteristics in the altitude wind tunnel. The engine characteristics obtained by use of the pressure valve were compared with those obtained with a bellmouth inlet operating in simulated free-stream conditions.
Date: April 6, 1956
Creator: Wallner, Lewis E.; Lubick, Robert J. & Bloomer, Harry E.
Partner: UNT Libraries Government Documents Department

Resonance Control Cooling System for the APT/LEDA RFQ

Description: The Radio Frequency Quadrupole (RFQ) resonance control cooling system (RCCS) for the Low Energy Demonstration Accelerator (LEDA) in support of the Accelerator Production of Tritium (APT) is described. Constant flow regulating valves to distribute the required flow to the 424 channels and to permit use of centrifugal pumps is discussed. Control system schema are described to regulate resonance frequency during steady state operation.
Date: November 4, 1998
Creator: Domer, G.A. & Floersch, R.H.
Partner: UNT Libraries Government Documents Department

Tests of Air Valves for Intermittent-Jet Engines at Speeds of 20 and 25 Cycles Per Second

Description: Report discussing a study of automatic nonreturn air valves for use in an intermittent-jet engine. Four valve-spring materials, three valve-grill materials, and five types of valves were used. Valve A, which was made out of aluminum, was found to perform the best and last the longest.
Date: May 8, 1945
Creator: Bressman, Joseph R. & McCready, Robert J.
Partner: UNT Libraries Government Documents Department