A fluid temperature interpolation method for wide temperature range distributed flow calorimeter.

Area of Science:

• Thermodynamics
• Fluid dynamics
• Aerospace engineering

Background:

• Accurate thermodynamic characterization of hydrocarbon fuels is crucial for developing advanced propulsion systems, particularly for hypersonic flight.
• Traditional flow calorimetry faces challenges in precisely monitoring fluid temperatures within tubes under high-temperature operational conditions.
• Understanding fluid temperature is essential for determining thermodynamic parameters like reaction and mixing enthalpies.

Purpose of the Study:

• To propose and validate a novel distributed method for calculating fluid temperature in tubes under high-temperature conditions.
• To enhance the accuracy of thermodynamic measurements for hydrocarbon fuels used in aerospace applications.
• To provide a foundation for improved selection and development of fuels for hypersonic flight.

Main Methods:

• Developed a distributed method interpolating the enthalpy function through experiments at varying power levels.
• Utilized microelement analysis to calculate fluid temperature within narrow pipes across a wide temperature range.
• Established and verified a simulation model of the flow calorimeter using numerical simulations.

Main Results:

• The proposed methodology was validated through numerical simulations of the flow calorimeter.
• Experimental validation using n-decane in the temperature range of 295.50–609.38 K showed a relative error of -0.61% to 1.24%.
• The method demonstrated effective estimation of fluid temperature within the distributed flow calorimeter.

Conclusions:

• The developed distributed method provides an effective means to estimate fluid temperature in flow calorimeters.
• This technique enhances the capability to measure key thermodynamic parameters for hydrocarbon fuels.
• The findings support the advancement of fuel selection and design for hypersonic flight applications.