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NACA-TN-3344
Theoretical and experimental investigation of aerodynamic-heating and isothermal heat-transfer parameters on a hemispherical nose with laminar boundary layer at supersonic Mach numbers
Year: 1954
Abstract: The effect of a strong, negative pressure gradient upon the local rate of heat transfer through a laminar boundary layer on the isothermal surface of an electrically heated, cylindrical body of revolution with a hemispherical nose was determined from wind-tunnel tests at a Mach number of 1.97. The investigation indicated that the local heat-transfer parameter, Nu/√Re, based on flow conditions just outside the boundary layer, decreased from a value of 0.65 ±0.10 at the stagnation point of the hemisphere to a value of 0.43 ±0.05 at the junction with the cylindrical afterbody. Because measurements of the static pressure distribution over the hemisphere indicated that the local flow pattern tended to become stationary as the free-stream Mach number was increased to 3.8, this distribution of heat-transfer parameter is believed representative of all Mach numbers greater than 1.97 and of temperatures less than that of dissociation. The local heat-transfer parameter was independent of Reynolds number based on body diameter in the range from 0.6x106 to 2.3x106.
The measured distribution of heat-transfer parameter agreed within ±18 percent with an approximate theoretical distribution calculated with foreknowledge only of the pressure distribution about the body. This method, applicable to any body of revolution with an isothermal surface, combines the Mangler transformation, Stewartson transformation, and thermal solutions to the Falkner-Skan wedge-flow problem, and thus evaluates the heat-transfer rate in axisymmetric compressible flow in terms of the known heat-transfer rate in an approximately equivalent two-dimensional incompressible flow.
The measured distribution of heat-transfer parameter agreed within ±18 percent with an approximate theoretical distribution calculated with foreknowledge only of the pressure distribution about the body. This method, applicable to any body of revolution with an isothermal surface, combines the Mangler transformation, Stewartson transformation, and thermal solutions to the Falkner-Skan wedge-flow problem, and thus evaluates the heat-transfer rate in axisymmetric compressible flow in terms of the known heat-transfer rate in an approximately equivalent two-dimensional incompressible flow.
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| contributor author | NASA - National Aeronautics and Space Administration (NASA) | |
| date accessioned | 2017-09-04T18:19:40Z | |
| date available | 2017-09-04T18:19:40Z | |
| date copyright | 01/01/1954 | |
| date issued | 1954 | |
| identifier other | HUNUYDAAAAAAAAAA.pdf | |
| identifier uri | http://yse.yabesh.ir/std;jsery=autho162s7D8308/handle/yse/202326 | |
| description abstract | The effect of a strong, negative pressure gradient upon the local rate of heat transfer through a laminar boundary layer on the isothermal surface of an electrically heated, cylindrical body of revolution with a hemispherical nose was determined from wind-tunnel tests at a Mach number of 1.97. The investigation indicated that the local heat-transfer parameter, Nu/√Re, based on flow conditions just outside the boundary layer, decreased from a value of 0.65 ±0.10 at the stagnation point of the hemisphere to a value of 0.43 ±0.05 at the junction with the cylindrical afterbody. Because measurements of the static pressure distribution over the hemisphere indicated that the local flow pattern tended to become stationary as the free-stream Mach number was increased to 3.8, this distribution of heat-transfer parameter is believed representative of all Mach numbers greater than 1.97 and of temperatures less than that of dissociation. The local heat-transfer parameter was independent of Reynolds number based on body diameter in the range from 0.6x106 to 2.3x106. The measured distribution of heat-transfer parameter agreed within ±18 percent with an approximate theoretical distribution calculated with foreknowledge only of the pressure distribution about the body. This method, applicable to any body of revolution with an isothermal surface, combines the Mangler transformation, Stewartson transformation, and thermal solutions to the Falkner-Skan wedge-flow problem, and thus evaluates the heat-transfer rate in axisymmetric compressible flow in terms of the known heat-transfer rate in an approximately equivalent two-dimensional incompressible flow. | |
| language | English | |
| title | NACA-TN-3344 | num |
| title | Theoretical and experimental investigation of aerodynamic-heating and isothermal heat-transfer parameters on a hemispherical nose with laminar boundary layer at supersonic Mach numbers | en |
| type | standard | |
| page | 49 | |
| status | Active | |
| tree | NASA - National Aeronautics and Space Administration (NASA):;1954 | |
| contenttype | fulltext |