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Compressibility and Heating Effects on Pressure Loss and Cooling of a Baffled Cylinder Barrel

Description: "Theoretical investigations have shown that, because air is compressible, the pressure-drop requirements for cooling an air-cooled engine will be much greater at high altitudes and high speeds than at sea level and low speeds. Tests were conducted by the NACA to obtain some experimental confirmation of the effect of air compressibility on cooling and pressure loss of a baffled cylinder barrel and to evaluate various methods of analysis. The results reported in the present paper are regarded as preliminary to tests on single-cylinder and multi-cylinder engines. Tests were conducted over a wide range of air flows and density altitudes" (p. 185).
Date: July 1, 1944
Creator: Goldstein, Arthur W. & Ellerbrock, Herman H., Jr.
Partner: UNT Libraries Government Documents Department

Compressibility and Heating Effects on Pressure Loss and Cooling of a Baffled Cylinder Barrel

Description: "Theoretical investigations have shown that, because air is compressible, the pressure-drop requirements for cooling an air-cooled engine will be much greater at high altitudes and high speeds than at sea level and low speeds. Tests were conducted by the NACA to obtain some experimental confirmation of the effect of air compressibility on cooling and pressure loss of a baffled cylinder barrel and to evaluate various methods of analysis. The results reported in the present paper are regarded as preliminary to tests on single-cylinder and multicylinder engines. Tests were conducted over a wide range of air flows and density altitudes" (p. 1).
Date: July 1, 1944
Creator: Goldstein, Arthur W. & Ellerbrock, Herman H., Jr.
Partner: UNT Libraries Government Documents Department

Method for Determining Pressure Drop of Air Flowing Through Constant-Area Passages for Arbitrary Heat-Input Distributions

Description: Report presenting a method for convenient determination of the pressure drop sustained by air flowing at high subsonic speeds in a constant-area passage under the simultaneous influence of friction and heat addition. Air-pressure-drop working charts based on the method are presented.
Date: September 1950
Creator: Pinkel, Benjamin; Noyes, Robert N. & Valerino, Michael F.
Partner: UNT Libraries Government Documents Department

Pressure drop across finned cylinders enclosed in a jacket

Description: The pressure drop across finned cylinders in a jacket for a range of air speeds from approximately 13 to 230 miles per hour has been investigated. Tests were made to determine the effect on the pressure drop of changes in fin space, fin width, jacket entrance and exit areas, skirt-approach radius, and the use of fillets and a separator plate at the rear of the cylinder. The pressure drop across the cylinder increased as the fin space decreased, the increase being very rapid at fin spaces smaller than approximately 0.20 inch. Fin width had little effect on the pressure drop for the range of widths tested. The pressure drop across the cylinder was nearly halved by increasing the skirt-approach radius from 3/4 inch to 1-1/4 inches, but fillets and a separator plate at the rear of the cylinder had little effect on the pressure drop. The pressure drop across a cylinder with tapered fins was greater than that for a cylinder having rectangular fins with the same effective fin spacing.
Date: November 1937
Creator: Rollin, Vern G. & Ellerbrock, Herman H., Jr.
Partner: UNT Libraries Government Documents Department

An investigation of aircraft heaters 23: measured and predicted performance of a flat-plate type exhaust gas and air heat exchanger

Description: Report presenting results of tests of the thermal performance and the static pressure drop characteristics of a flat-plate type exhaust gas and air heat exchanger. The ventilating air shroud built into the heat exchanger gives characteristics of cross flow and parallel flow.
Date: April 1945
Creator: Boelter, L. M. K.; Guibert, A. G.; Rademacher, J. M. & Sanders, V. D.
Partner: UNT Libraries Government Documents Department

Pressure-drop characteristics of a 22-segment mock-up of the General Electric Company air-cooled aircraft reactor

Description: Report presenting an investigation to obtain pressure-drop data for flow of air with no heat addition on a 22-segment mock-up of the GE aircraft reactor. Pressure-drop data were obtained over a range of Reynolds numbers, Mach numbers, and inlet-air pressures.
Date: January 20, 1955
Creator: Sams, Eldon W. & Weiland, Walter F., Jr.
Partner: UNT Libraries Government Documents Department

Simple Curves for Determining the Effects of Compressibility on Pressure Drop Through Radiators

Description: Report presenting simple curves by which the basic pressure-drop characteristics of unheated tubular radiators can be corrected to operating conditions in which the radiator is heated and in which the Mach number of the tube flow is of appreciable magnitude. The only data required for the use of the curves are the radiator dimensions, the rate of heat input, the pressure and temperature ahead of the radiator, and the rate of mass flow of air through the radiator.
Date: September 1944
Creator: Becker, John V. & Baals, Donald D.
Partner: UNT Libraries Government Documents Department

Experimental Investigation of Entrance-Region Heat-Transfer Coefficients

Description: "Experimental results of tests made at the Langley Memorial Aeronautical Laboratory are presented to show how heat-transfer coefficients can be increased by a method utilizing the high rate of heat transfer known to exist on any heat-transfer surface in the region adjacent to the edge on which the cooling or heating fluid impinges. The results show that, for the same pressure drop, the average surface heat-transfer.coefficient can be increased 50 to 100 percent when a cooling surface having a length of four inches in the direction of fluid flow is cut to form twenty fins with a length of 0.2 inch in the direction of fluid flow and the fins are sharpened and staggered in the air stream" (p. 1).
Date: November 1943
Creator: Joyner, Upshur T.
Partner: UNT Libraries Government Documents Department

Pressure Drop in Tubing in Aircraft Instrument Installations

Description: "The theoretical basis of calculation of pressure drop in tubing is reviewed briefly. The effect of pressure drop in connecting tubing upon the operation and indication of aircraft instruments is discussed. Approximate equations are developed, and charts and tables based upon them are presented for use in designing installations of altimeters, air-speed indicators, rate-of-climb indicators, and air-driven gyroscopic instruments" (p. 1).
Date: February 1937
Creator: Wildhack, W. A.
Partner: UNT Libraries Government Documents Department

Pressure-Drop Characteristics of Orifice Plates Used to Simulate Radiators

Description: Report presenting an investigation of the pressure-drop characteristics of orifice plates, which has been conducted to facilitate the design of resistances to simulate various types of cooling units. This use of the orifice plates was found to be practical because of the simple construction of the plates, the ease of which pressure drop can be varied by use of corks, and the absence of any large scale effects.
Date: March 1942
Creator: Czarnecki, K. R.
Partner: UNT Libraries Government Documents Department

Measurements of Pressure Drop with No Heat Addition on Mockup Segments of the General Electric Air-Cooled Aircraft Reactor

Description: "An investigation was conducted at the NACA Lewis laboratory to obtain pressure-drop data for flow of air with no heat addition through mockups of two reactor segments of the proposed General Electric Company aircraft reactor. Pressure-drop data were obtained over a range of Reynolds numbers from 4000 to 80,000, air inlet Mach numbers from 0.02 to 0.40, inlet pressures up to about 40 inches of mercury absolute, and ambient air temperatures. factors, corrected for entrance, vena contracta, momentum, and exit losses, are considerably higher at the high Reynolds numbers than those reported for turbulent flow in smooth pipes" (p. 1).
Date: November 7, 1952
Creator: Sams, Eldon W. & Nagey, Tibor F.
Partner: UNT Libraries Government Documents Department

Flow Tests of an NACA-Designed Supercharger Inlet Elbow and the Effects of Various Components on the Flow Characteristics at the Elbow Outlet

Description: Note presenting an investigation on a supercharger inlet elbow designed to have a uniform velocity distribution at the outlet with a minimum pressure loss through the bend. The effects of a vane, an impeller-shaft housing, and the combination of the two on the outlet-velocity distribution and total pressure drop through the elbow were determined.
Date: October 1946
Creator: Guentert, D. C.; Todd, D. J. & Simmons, W. P., Jr.
Partner: UNT Libraries Government Documents Department

Experimental Determination of Pressure Drop Caused by Wire Gauze in an Air Stream

Description: "For several kinds of wire gauze the difference in static, dynamic and total or absolute pressure in front of and behind the gauze were determined for comparison with the pressure drop caused by an airplane radiator, such gauze being used on airplane models to represent the radiator" (p. 1).
Date: January 1925
Partner: UNT Libraries Government Documents Department

Chart for simplifying calculations of pressure drop of a high-speed compressible fluid under simultaneous action of friction and heat transfer - application to combustion-chamber cooling passages

Description: Report presenting a method for calculating the pressure drop of a high-speed compressible fluid in a constant-area duct under the simultaneous action of friction and heat transfer. The temperature distribution assumed in the development of the working chart can be made to closely approximate, in on one or two steps, the temperature distributions found in the cooling passages of ramjet and tail-pipe-burner combustion chambers.
Date: March 1950
Creator: Sibulkin, Merwin & Koffel, William K.
Partner: UNT Libraries Government Documents Department

Compressibility Effects on Heat Transfer and Pressure Drop in Smooth Cylindrical Tubes

Description: "An analysis is made to simplify pressure-drop calculations for nonadiabatic and adiabatic friction flow of air in smooth cylindrical tubes when the density changes due to heat transfer and pressure drop are appreciable. Solutions of the equation of motion are obtained by the use of Reynolds' analogy between heat transfer and skin friction. Charts of the solutions are presented for making pressure-drop calculations" (p. 1).
Date: October 1944
Creator: Nielsen, Jack N.
Partner: UNT Libraries Government Documents Department

High-Altitude Cooling 2: Air-Cooled Engines

Description: Report presenting the heat-transfer theory for air-cooled engines and an analysis of the cooling pressure drop for the case in which the pressure drop is an appreciable fraction of the absolute pressure. A chart is given for the simple determination of the cooling pressure drop predicted on the basis of the usual type of sea-level cooling-correlation tests.
Date: September 1944
Creator: Williams, David T.
Partner: UNT Libraries Government Documents Department

Scale-Up of Alternate HRT Core

Description: "In order to determine the factors involved in the scale-up of cores with concentric inlet and outlet pipes, a 48 inch carbon steel flow model, geometrically similar to a 6 foot diameter core, has been assembled and tested...Visual studies were made of dye and gas behavior in the sphere, and quantitative measurements of point residence times were obtained through the use of conductivity cells actuating a Brush recorder. Static pressure drop across the core was measured."
Date: May 7, 1954
Creator: Lesem, L. B. & Harley, P. H.
Partner: UNT Libraries Government Documents Department

Two-Phase Frictional Pressure Drop Multipliers for SUVA R-134a Flowing in a Rectangular Duct

Description: The adiabatic two-phase frictional multipliers for SUVA, R-134a flowing in a rectangular duct (with D{sub H} = 4.8 mm) have been measured for 3 nominal system pressures (0.9 MPa, 1.38 MPa and 2.41 MPa) and 3 nominal mass fluxes (510, 1020 and 2040 kg/m{sup 2}/s). The data is compared with several classical correlations to assess their predictive capabilities. The Lockhart-Martinelli model gives reasonable results at the lowest pressure and mass flux, near the operating range of most refrigeration systems, but gives increasingly poor comparisons as the pressure and mass flux is increased. The Chisholm B-coefficient model is found to best predict the data over the entire range of test conditions; however, there is significant disagreement at the highest pressure tested (with the model over predicting the data upwards of 100% for some cases). The data shows an increased tendency toward homogeneous flow as the pressure and flow rate are increased, and in fact the homogeneous model best predicts the bulk of the data at the highest pressure tested.
Date: December 13, 2004
Creator: Vassallo, P & Keller, K
Partner: UNT Libraries Government Documents Department

Axial Pressure Drop Measurements during Pilot-Scale Testing of a Mott Crossflow Filter

Description: The Department of Energy selected CSSX as the preferred cesium removal technology for Savannah River Site waste. As a pretreatment step for the CSSX flowsheet, personnel contact the incoming salt solution that contains entrained sludge with MST to adsorb strontium and select actinides. They filter the resulting slurry to remove the sludge and MST. The filtrate receives further treatment to remove cesium in the solvent extraction system. The baseline filtration technology uses a Mott crossflow filter. We conducted pilot-scale crossflow filter testing with simulated SRS high level waste to evaluate the impact of operating parameters on the crossflow filtration process. The tests employed 0.5 micron and 0.1 micron filters. The feed slurries for these tests included simulated sludge plus MST, simulated sludge only, and simulated sludge plus manganese oxide solids. The supernate for these tests consisted of 5.6-6.4 M sodium, average salt solution. During the tests, we measured the axial pressure drop as a function of axial velocity, feed slurry, and insoluble solids concentration. This report documents the axial pressure drop data.
Date: June 24, 2004
Creator: POIRIER, MICHAEL
Partner: UNT Libraries Government Documents Department

Irrecoverable pressure loss coefficients for two elbows in series with various orientation angles and separation distances

Description: Test data is described for two ninety degree elbows that are in series for a piping network. Both elbows had a radius of curvature of 1.2. Three relative angles and seven different separation distances were investigated. The overall irrecoverable pressure loss for the two elbows is characterized relative to the irrecoverable pressure loss for a single elbow. In addition to providing design guidance relative to the net irrecoverable pressure loss for multiple elbows, the data provides a data base for helping qualify computational fluid dynamics (CFD) computer codes used to predict the irrecoverable pressure loss in piping systems.
Date: May 1, 1997
Creator: Coffield, R.D.; McKeown, P.T. & Hammond, R.B.
Partner: UNT Libraries Government Documents Department

Qualification of a Method to Calculate the Irrecoverable Pressure Loss in High Reynolds Number Piping Systems

Description: High Reynolds number test data has recently been reported for both single and multiple piping elbow design configurations at earlier ASME Fluid Engineering Division conferences. The data of these studies ranged up to a Reynolds number of 42 x 10[sup]6 which is significantly greater than that used to establish design correlations before the data was available. Many of the accepted design correlations, based on the lower Reynolds number data, date back as much as fifty years. The new data shows that these earlier correlations are extremely conservative for high Reynolds number applications. Based on the recent high Reynolds number information a new recommended method has been developed for calculating irrecoverable pressure loses in piping systems for design considerations such as establishing pump sizing requirements. This paper describes the recommended design approach and additional testing that has been performed as part of the qualification of the method. This qualification testing determined the irrecoverable pressure loss of a piping configuration that would typify a limiting piping section in a complicated piping network, i.e., multiple, tightly coupled, out-of-plane elbows in series under high Reynolds number flow conditions. The overall pressure loss measurements were then compared to predictions, which used the new methodology to assure that conservative estimates for the pressure loss (of the type used for pump sizing) were obtained. The recommended design methodology, the qualification testing and the comparison between the predictions and the test data are presented. A major conclusion of this study is that the recommended method for calculating irrecoverable pressure loss in piping systems is conservative yet significantly lower than predicted by early design correlations that were based on the extrapolation of low Reynolds number test data.
Date: September 1, 2002
Creator: Sigg, K. C. & Coffield, R. D.
Partner: UNT Libraries Government Documents Department

Flow Regimes of Air-Water Counterflow Through Cross Corrugated Parallel Plates

Description: Heretofore unknown flow regimes of air-water counterflow through a pair of transparent vertical parallel cross corrugated plates were observed via high-speed video. Air flows upward driven by pressure gradient and water, downward driven by gravity. The crimp geometry of the corrugations was drawn from typical corrugated sheets used as filling material in modern structured packed towers. Four regimes were featured, namely, rivulet, bicontinuous, flooding fronts, and flooding waves. It is conceivable that the regimes observed might constitute the basis for understanding how gas and liquid phases contend for available space in the interstices of structured packings in packed towers. Flow regime transitions were expressed in terms of liquid load (liquid superficial velocity) and gas flow factor parameters commonly used in pressure drop and capacity curves. We have carefully examined the range of parameters equivalent to the ill-understood high-liquid-flow operation in packed towers. More importantly, our findings should prove valuable in validating improved first-principles modeling of gas-liquid flows in these industrially important devices.
Date: June 7, 2000
Creator: de Almeida, V.F.
Partner: UNT Libraries Government Documents Department