ASTM E637-05(2011)
Standard Test Method for Calculation of Stagnation Enthalpy from Heat Transfer Theory and Experimental Measurements of Stagnation-Point Heat Transfer and Pressure

Standard No.

ASTM E637-05(2011)

Release Date

2005

Published By

American Society for Testing and Materials (ASTM)

Status

Be replaced

Replace By

ASTM E637-05(2016)

Latest

ASTM E637-22

Scope

The purpose of this test method is to provide a standard calculation of the stagnation enthalpy of an aerodynamic simulation device using the heat transfer theory and measured values of stagnation point heat transfer and pressure. A stagnation enthalpy obtained by this test method gives a consistent set of data, along with heat transfer and stagnation pressure for ablation computations.

1.1 This test method covers the calculation from heat transfer theory of the stagnation enthalpy from experimental measurements of the stagnation-point heat transfer and stagnation pressure.

1.2 Advantages:

1.2.1 A value of stagnation enthalpy can be obtained at the location in the stream where the model is tested. This value gives a consistent set of data, along with heat transfer and stagnation pressure, for ablation computations.

1.2.2 This computation of stagnation enthalpy does not require the measurement of any arc heater parameters.

1.3 Limitations and Considerations8212;There are many factors that may contribute to an error using this type of approach to calculate stagnation enthalpy, including:

1.3.1 Turbulence8212;The turbulence generated by adding energy to the stream may cause deviation from the laminar equilibrium heat transfer theory.

1.3.2 Equilibrium, Nonequilibrium, or Frozen State of Gas8212;The reaction rates and expansions may be such that the gas is far from thermodynamic equilibrium.

1.3.3 Noncatalytic Effects8212;The surface recombination rates and the characteristics of the metallic calorimeter may give a heat transfer deviation from the equilibrium theory.

1.3.4 Free Electric Currents8212;The arc-heated gas stream may have free electric currents that will contribute to measured experimental heat transfer rates.

1.3.5 Nonuniform Pressure Profile8212;A nonuniform pressure profile in the region of the stream at the point of the heat transfer measurement could distort the stagnation point velocity gradient.

1.3.6 Mach Number Effects8212;The nondimensional stagnation-point velocity gradient is a function of the Mach number. In addition, the Mach number is a function of enthalpy and pressure such that an iterative process is necessary.

1.3.7 Model Shape8212;The nondimensional stagnation-point velocity gradient is a function of model shape.

1.3.8 Radiation Effects8212;The hot gas stream may contribute a radiative component to the heat transfer rate.

1.3.9 Heat Transfer Rate Measurement8212;An error may be made in the heat transfer measurement (see Method E469 and Test Methods E422, E457, E459, and E511).

1.3.10 Contamination8212;The electrode mater......

ASTM E637-05(2011) Referenced Document

• ASTM E341 Standard Practice for Measuring Plasma Arc Gas Enthalpy by Energy Balance
• ASTM E422 Standard Test Method for Measuring Heat Flux Using a Water-Cooled Calorimeter
• ASTM E457 Standard Test Method for Measuring Heat-Transfer Rate Using a Thermal Capacitance (Slug) Calorimeter
• ASTM E459 Standard Test Method for Measuring Heat Transfer Rate Using a Thin-Skin Calorimeter
• ASTM E511 Standard Test Method for Measuring Heat Flux Using a Copper-Constantan Circular Foil, Heat-Flux Gage

ASTM E637-05(2011) history

• 2022 ASTM E637-22 Standard Test Method for Calculation of Stagnation Enthalpy from Heat Transfer Theory and Experimental Measurements of Stagnation-Point Heat Transfer and Pressure
• 2005 ASTM E637-05(2016) Standard Test Method for Calculation of Stagnation Enthalpy from Heat Transfer Theory and Experimental Measurements of Stagnation-Point Heat Transfer and Pressure
• 2005 ASTM E637-05(2011) Standard Test Method for Calculation of Stagnation Enthalpy from Heat Transfer Theory and Experimental Measurements of Stagnation-Point Heat Transfer and Pressure
• 2005 ASTM E637-05 Standard Test Method for Calculation of Stagnation Enthalpy from Heat Transfer Theory and Experimental Measurements of Stagnation-Point Heat Transfer and Pressure
• 1998 ASTM E637-98 Standard Test Method for Calculation of Stagnation Enthalpy from Heat Transfer Theory and Experimental Measurements of Stagnation-Point Heat Transfer and Pressure