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Simple graphical solution of heat transfer and evaporation from surface heated to prevent icing

Description: "Equations expressing the heat transfer and evaporation from wetted surfaces during ice prevention have been simplified and regrouped to permit solutions by simple graphical means. Working charts for quick and accurate anti-icing calculations are also included" (p. 1).
Date: October 1952
Creator: Gray, Vernon H.
Partner: UNT Libraries Government Documents Department

An Approximate Method of Calculation of Relative Humidity Required to Prevent Frosting on Inside of Aircraft Pressure Cabin Windows, Special Report

Description: This report has been prepare in response to a request for information from an aircraft company. A typical example was selected for the presentation of an approximate method of calculation of the relative humidity required to prevent frosting on the inside of a plastic window in a pressure type cabin on a high speed airplane. The results of the study are reviewed.
Date: December 5, 1940
Creator: Jones, Alun R.
Partner: UNT Libraries Government Documents Department

Impingement of water droplets on wedges and double-wedge airfoils at supersonic speeds

Description: "An analytical solution has been obtained for the equations of motion of water droplets impinging on a wedge in a two-dimensional supersonic flow field with a shock wave attached to the wedge. The closed-form solution yields analytical expressions for the equation of the droplet trajectory, the local rate of impingement and the impingement velocity at any point on the wedge surface, and the total rate of impingement. The analytical expressions are utilized to determine the impingement on the forward surfaces of diamond airfoils in supersonic flow fields with attached shock waves" (p. 85).
Date: April 21, 1953
Creator: Serafini, John S.
Partner: UNT Libraries Government Documents Department

Refrigerated wind tunnel tests on surface coatings for preventing ice formation

Description: "This investigation was conducted to determine the effectiveness of various surface coatings as a means for preventing ice formations on aircraft in flight. The substances used as coatings for these tests are divided into two groups: compounds soluble in water, and those which are insoluble in water. It was found that certain soluble compounds were apparently effective in preventing the formation of ice on an airfoil model, while all insoluble compounds which were tested were found to be ineffective" (p. 1).
Date: May 1930
Creator: Knight, Montgomery & Clay, William C.
Partner: UNT Libraries Government Documents Department

Flight tests of several exhaust-gas-to-air heat exchangers

Description: Report presenting an investigation of thirteen exhaust-gas-to-air heat exchangers to determine the practicability of the use of such heat exchangers in the thermal ice-prevention systems on aircraft. The results show that the exchangers constitute an excellent source of heated air for aircraft ice prevention and can be constructed to resist thermal and vibrational stresses.
Date: March 1944
Creator: Jackson, Richard & Hillendahl, Wesley H.
Partner: UNT Libraries Government Documents Department

An Analytical Investigation of the Heat Losses from a U.S. Navy K-Type Airship

Description: From Summary: "The heat losses from the envelope surface of a U.S. Navy K-type airship are evaluated to determine if the use of heat is a feasible means of preventing ice and snow accumulations on lighter-than-air craft during flight and when moored uncovered. Consideration is given to heat losses in clear air (no liquid water present in the atmosphere) and in probable conditions of icing and snow. The results of the analysis indicate that the amount of heat required in flight to raise the surface temperature of the entire envelope to the extent considered adequate for ice protection, based on experience with tests of heavier-than-air craft, is very large."
Date: February 17, 1947
Creator: Hillendahl, Wesley H. & George, Ralph E.
Partner: UNT Libraries Government Documents Department

Effectiveness of Thermal-Pneumatic Airfoil-Ice-Protection System

Description: From Summary: "Icing and drag investigations were conducted in the NACA Lewis icing research tunnel employing a combination thermal-pneumatic de-icer mounted on a 42-inch-chord NACA 0018 airfoil. The de-icer consisted of a 3-inch-wide electrically heated strip symmetrically located about the leading edge with inflatable tubes on the upper and lower airfoil surfaces aft of the heated area. The entire de-icer extended to approximately 25 percent of chord. A maximum power density of 9.25 watts per square inch was required for marginal ice protection on the airfoil leading edge at an air temperature of 00 F and an airspeed of 300 miles per hour."
Date: April 13, 1951
Creator: Gowan, William H., Jr. & Mulholland, Donald R.
Partner: UNT Libraries Government Documents Department

Icing-protection requirements for reciprocating-engine induction system

Description: From Summary: "Despite the development of relatively ice-free fuel-metering systems, the widespread use of alternate and heated-air intakes, and the use of alcohol for emergency de-icing, icing of aircraft-engine induction systems is a serious problem. Investigations have been made to study and to combat all phases of this icing problem. From these investigations, criterions for safe operation and for design of new induction systems have been established. The results were obtained from laboratory investigations of carburetor-supercharger combinations, wind-tunnel investigations of air scoops, multicylinder-engine studies, and flight investigations. Characteristics of three forms of ice, impact, throttling, and fuel evaporation were studied."
Date: June 20, 1949
Creator: Coles, Willard D.; Rollin, Vern G. & Mulholland, Donald R.
Partner: UNT Libraries Government Documents Department

Investigation of Effectiveness of Air-Heating a Hollow Steel Propeller for Protection Against Icing. 3: 25% Partitioned Blades

Description: From Summary: "The icing protection obtained from an internally air-heated propeller blade partitioned to confine the heated air forward of 25-percent chord was investigated in the NACA Cleveland icing research tunnel. A production-model hollow steel propeller was modified with an Internal radial partition at 25-percent chord and with shank and tip openings to admit and exhaust the heated air. Temperatures were measured on the blade surfaces and in the heated-air system during tunnel icing conditions. Heat-exchanger effectiveness and photographs of Ice formations on the blades were obtained."
Date: May 1948
Creator: Mulholland, Donald R. & Perkins, Porter J.
Partner: UNT Libraries Government Documents Department

Inlet Icing and Effectiveness of Hot-Gas Bleedback for Ice Protection of Turbojet Engine

Description: Report presenting an investigation of icing and ice protection at the inlet of a turbojet engine in the altitude wind tunnel. A method of ice protection was studied that uses hot gas bled from a turbine inlet and injected into the air stream ahead of the compressor inlet. Ice was either prevented or accumulated slowly at various engine speed levels.
Date: November 26, 1948
Creator: Fleming, William A. & Saari, Martin J.
Partner: UNT Libraries Government Documents Department

Investigation of heat transfer from a stationary and rotating ellipsoidal forebody of fineness ratio 3

Description: From Summary: "The convective heat transfer from the surface of an ellipsoidal forebody of fineness ratio 3 and 20-inch maximum diameter was investigated in clear air for both stationary and rotating operation over a range of conditions including air speeds up to 240 knots, rotational speeds up to 1200 rpm, and angles of attack of 0 deg, 3 deg, and 6 deg. The results are presented in the form of heat-transfer coefficients and the correlation of Nusselt and Reynolds numbers. Both a uniform surface temperature and a uniform input heater density distribution were used."
Date: November 1956
Creator: Lewis, James P. & Ruggeri, Robert S.
Partner: UNT Libraries Government Documents Department

Investigation of Heat Transfer from a Stationary and Rotating Conical Forebody

Description: From Summary: "The convective heat transfer from the surface of a conical forebody having a hemispherical nose, an included angle of approximately 30 deg, and. a maximum diameter of 18.9 inches was investigated in a wind tunnel for both stationary and. rotating operation. The range of test conditions included free-stream velocities up to 400 feet per second, rotational speeds up to 1200 rpm, and. angles of attack of 0 deg and 6 deg. Both a uniform surface temperature and a uniform heater input power density were used."
Date: October 1957
Creator: Ruggeri, Robert S. & Lewis, James P.
Partner: UNT Libraries Government Documents Department

A method for calculating heat transfer in the laminar flow region of bodies

Description: This report has been prepared to provide a practical method for determining the chordwise distribution of the rate of heat transfer from the surface of a wing or body of revolution to air. The method is limited in use to the determination of heat transfer from the forward section of such bodies when the flow is laminar. A comparison of the calculated average heat-transfer coefficient for the nose section of the wing of a Lockheed 12-A airplane with that experimentally determined shows a satisfactory agreement. A sample calculation is appended.
Date: 1943
Creator: Allen, H. Julian & Look, Bonne C.
Partner: UNT Libraries Government Documents Department

A preliminary study of the prevention of ice on aircraft by the use of engine-exhaust heat

Description: "An investigation was made in the N.A.C.A. ice tunnel at air temperatures from 20 degrees to 28 degrees Fahrenheit and at a velocity of 80 miles per hour to determine whether ice formations on a model wing could be prevented by the use of the heat from the engine-exhaust gas. Various spanwise duct systems were tested in a 6-foot-chord N.A.C.A. 23012 wing model. The formation of ice over the entire wing chord was prevented by the direct heating of the forward 10 percent of the wing by hot air, which was passed through leading-edge ducts" (p. 1).
Date: June 1939
Creator: Rodert, Lewis A.
Partner: UNT Libraries Government Documents Department

An Investigation of the Prevention of Ice on the Airplane Windshield

Description: "An investigation of three methods for the prevention and the removal of ice on an airplane windshield has been completed. The methods were: electric heating; hot-air heating; and an alcohol-dispensing, rotating wiper blade. The results showed that vision through the airplane windshield could be maintained during severe icing conditions by the use of heat" (p. 1).
Date: March 1940
Creator: Rodert, Lewis A.
Partner: UNT Libraries Government Documents Department

A flight investigation of the distribution of ice-inhibiting fluids on a propeller blade

Description: Report presenting an investigation of the flow of ice-inhibiting fluids over the blade surfaces of a 12.5-foot-daimeter propeller in flight by discharging dyed fluids at various stations along the leading edges of the blades. The effects on the distribution of varying the fluid composition, the blade-surface roughness, and the orifice design were also observed.
Date: September 1939
Creator: Rodert, Lewis A.
Partner: UNT Libraries Government Documents Department

An Investigation of a Thermal Ice-Prevention System for a C-46 Cargo Airplane 6: Dry-Air Performance of Thermal System at Several Twin- and Single-Engine Operating Conditions at Various Altitudes

Description: Report presenting flight tests to establish the dry-air-performance characteristics of a thermal ice-prevention system at various operating conditions and altitudes. Results regarding twin-engine tests and single-engine tests of characteristics such as skin temperatures and location of heating are provided.
Date: May 1945
Creator: Selna, James & Kees, Harold L.
Partner: UNT Libraries Government Documents Department

De-Icing Effectiveness of External Electric Heaters for Propeller Blades

Description: Note presenting an investigation in the icing research tunnel to determine the icing protection provided by external rubber-clad blade heaters at several icing, heating, and propeller operating conditions. Data are presented to show the effect of propeller speed, ambient-air temperature, liquid-water concentration, heating-power density, duration of heating, and total cycle times on the power requirements and de-icing performance of the blade heaters.
Date: February 1948
Creator: Lewis, James P.
Partner: UNT Libraries Government Documents Department

De-Icing Effectiveness of External Electric Heaters for Propeller Blades

Description: Note presenting an investigation in the icing research tunnel to determine the icing protection provided by external rubber-clad blade heaters at several icing, heating, and propeller operating conditions. Data are presented to show the effect of propeller speed, ambient-air temperature, liquid-water concentration, heating-power density, duration of heating, and total cycle times on the power requirements and de-icing performance of the blade heaters.
Date: February 1948
Creator: Lewis, James P.
Partner: UNT Libraries Government Documents Department

The Calculation of the Heat Required for Wing Thermal Ice Prevention in Specified Icing Conditions

Description: Note presenting a verification of previously derived equations for calculating the rate of heat transfer from airfoils in icing conditions, which have come about as a result of an investigation of the meteorological conditions conducive to the formation of ice on aircraft and a study of the process of airfoil thermal ice prevention. The results indicated that knowledge of these components has increased to a point where the design of heated wings on a fundamental, wet-air basis can now be undertaken with reasonable certainty.
Date: December 1947
Creator: Neel, Carr B., Jr.; Bergrun, Norman R.; Jukoff, David & Schlaff, Bernard A.
Partner: UNT Libraries Government Documents Department

The Formation of Ice Upon Exposed Parts of an Airplane in Flight

Description: In order to experimentally study the conditions leading to ice formation on aircraft surfaces, an aircraft was equipped with small auxiliary surfaces and aerodynamic shapes similar to struts, wires, Pitot heads, etc. This airplane was flown at an altitude where a temperature of 32 F was encountered, at such times as cloud formations could be found at the coincident altitude. Here it was discovered that ice formed rapidly in regard to quantity, character, shape, and rapidity of formation.
Date: July 1928
Creator: Carroll, Thomas & McAvoy, William H.
Partner: UNT Libraries Government Documents Department

The Prevention of the Ice Hazard on Airplanes

Description: A review of various methods to prevent ice formation and adhesion to aircraft surfaces is given. It was concluded that the adhesion of ice to a surface may be reduced somewhat by the application of certain waxes and varnishes. In the experiments described, the varnishes containing calcium stearate and calcium oleate gave the best results. In wind tunnel tests, the adhesion was further reduced by the application of these waxes and varnishes to a thin, heat insulating layer of rubber.
Date: July 1930
Creator: Geer, William C. & Scott, Merit
Partner: UNT Libraries Government Documents Department

Kinetic Temperature of Wet Surfaces: A Method of Calculating the Amount of Alcohol Required to Prevent Ice, and the Derivation of the Psychometric Equation

Description: Report presenting a method for calculating the temperature of a surface wetted either by a pure liquid, such as water, or by a mixture, such as alcohol and water. The method is applied to the problem of protecting, by alcohol, propellers and the induction system of the engine against ice. The psychrometric equation, used in wet-bulb hygrometry, is deduced in its general form.
Date: September 1945
Creator: Hardy, J. K.
Partner: UNT Libraries Government Documents Department

Effect of the Performance of a Turbosupercharged Engine of an Exhaust-Gas-to-Air Heat Exchanger for Thermal Ice Prevention

Description: This report presents the results of a flight investigation to determine the effect on the performance of a turbosupercharged engine of an exhaust-gas-to-air heat exchanger installed between the engine-exhaust collector ring and the turbosupercharger. The background, results, and discussion of the investigation are described.
Date: August 23, 1945
Creator: Look, Bonne C.
Partner: UNT Libraries Government Documents Department