Physico-chemical processes and materials in space conditions


Experiment Difusion Flame


Objective:

Obtaining high-precision experimental data for studying laminar diffusion flame in the concurrent stream of fuel and oxidizer.

Tasks:

  • Experimental study of the properties of diffusion flame of methane and ethane in the concurrent stream of air under microgravity conditions. Obtaining data about the shape of the flame, the height at which the suspended flame stabilizes, its temperature, soot formation and the limits of its existence depending on the flow rate and the mixture dilution. Obtaining data about soot-forming diffusion flame by changing the shape of the flame, the temperature of the gas in the soot-free area of the flame, soot luminosity, soot temperature and volumetric ratio of soot particles depending on the flow rate and the mixture dilution.
  • Development of procedures for analyzing experimental data on the basis of theoretical calculations of characteristics and structure of the diffusion flame under microgravity conditions and comparing analytical data with those obtained in the course of space experiment.
  • Providing scientifically proven recommendations on changing the modes of carrying out the space experiment.
  • Obtaining and processing experimental data, solving a number of inverse problems to extract kinetic data for detailed and reduced models of diffusion flame under microgravity conditions.

Equipment for the experiment:

  • a chamber with two orthogonal optical windows;
  • a burner made of two coaxial pipes;
  • ignition system;
  • gas feed and disposal system;
  • measuring instrumentation (optical and UV-cameras, radiometer, pressure and acceleration sensors, thermocouples, laser extinction and pyrometry unit, gas chromatograph);
  • control unit;
  • data processing and storage unit.

Experiment results:

  • video information with the images of the diffusion flame in the optical and UV bands;
  • radiant flux values both in the wide and the narrow spectral bands;
  • accompanying data: pressure in the chamber, temperature, gas composition.

Expected results:

There are plans to obtain enough experimental data to verify reaction mechanisms and new data on the dynamics/properties of diffusion flames.
Characteristics of the methane and ethylene diffusion flame in the concurrent air flow will be obtained for both highly diluted compositions and under soot-forming conditions depending on the inlet gas velocity and mixture dilution.
There are also plans to study the structure of lifting flame to avoid loss of heat in the burner device.
The results of these experiments will be directly applicable to practical issues related to turbulent combustion, ignition, flame stabilization and many others.