Anthony J. Marchese,
Associate ProfessorDepartment of Mechanical Engineering
College of Engineering
Rowan University, Glassboro, NJ 08028-1701
and
Department of Mechanical Engineering
College of Engineering
Rowan University, Glassboro, NJ 08028-1701
and
Frederick L. Dryer
Department of Mechanical and Aerospace Engineering
Princeton University
Princeton, NJ 08544
By conducting isolated droplet combustion experiments in microgravity, it is possible to generate spherically symmetric diffustion flames which can be modeled using detailed chemical kinetics and multi-component transport. Experiments are conducted in the 2.2 second drop tower facility, and the Zero Gravity Facility at NASA Lewis Research Center in Cleveland, OH.The experiments and modeling described here and on the following page were conducted to provide scientific support for similar experiments being conducted aboard the Space Shuttle. The first space-based droplet combustion experiment was called the Fiber Supported Droplet Experiment (FSDC-1). This experiment was part of United States Microgravity Laboratory-2 (USML-2) which was launched on October 20, 1995 on Space Shuttle Columbia mission STS-73. A second experiment called the Droplet Combustion Experiment (DCE) is part of Microgravity Science Laboratory-1 (MSL-1), which flew aboard the STS-83 Space Shuttle Columbia flight in April, 1997. A second fiber-supported droplet combusiton experiment, FSDC-2, was also conducted aboard MSL-1.
A more comprehensive web page on microgravity droplet combustion is maintained at Princeton University.
Methanol and methanol/water droplet combustion experiments have been conducted using the 2.2 second drop tower at NASA Lewis Research Center in Cleveland, OH. Experiments have been conducted in O2/N2 and O2/He environments at various pressures. The methanol droplet combustion apparatus used in the 2.2 second drop tower experiments is shown here:
The following is a sequence of video images from methanol droplet combustion experiment conducted using the 2.2 second drop tower at NASA Lewis Research Center. As the images show, the droplet is grown between two hypodermic needles which are rapidly retracted thereby deploying the droplet into the microgravity environment. The gas phase surrounding the liquid droplet is ignited symmetrically using two hot wire igniters.
In the experiment shown at left, the flame images has been acquired using an intensified array CCD camera fitted with an ultraviolet lens and a band-pass filter centered at 305 nm. This wavelength corresponds to emission from electronically excited hydroxyl radicals present within the flame. Comparisons between experiments and detailed kinetic modeling show that the location of maximum OH* emission coincides closely with the location of maximum temperature within the flame. Thus, the location of maximum OH* emission is ideal for defining the flame position.
The previous images of methanol droplet combustion in microgravity were obtained with a standard VCR camera. Notice that, in the final frame, the flame is indeed spherically symmetric and, since methanol does not produce soot, it is non-luminous.
Microgravity Combustion Links
Microgravity Combustion Papers
Miller, F.J., Easton, J. W., Marchese, A.J. and Ross, H.D. (2002). Gravitational Effects on Flame Spread Through Non-Homogeneous Gas Layers. Proc. Combust Inst. Accepted for Publication.
Nayagam, V., Marchese, A. J. and Sacksteder, K.R (2000). Microgravity droplet combustion: An inverse scale modeling problem? Third International Symposium on Scale Modeling, Nagoya, Japan, September, 2000.
Marchese, A. J., Dryer, F. L. and Nayagam, V. (1999). Numerical Modeling of Isolated N-Alkane Droplet Flames: Initial Comparisons with Ground and Space-Based Microgravity Experiments. Combust. Flame, 116, pp. 432-459.
Marchese, A. J. and Dryer, F. L. (1998). Radiative Effects in Space-Based Methanol/Water Droplet Combustion Experiments. Proc. Combust Inst. 27, pp. 1200-1208.
Nayagam, V., Haggard, J. B., Colantonio, R. O., Marchese, A.J., Dryer, F.L., Zhang, B. L. and Williams, F. A. (1998). N-Heptane Droplet Combustion in Oxygen-Helium Mixtures at Atmospheric Pressure. AIAA Journal. Vol. 36, No. 8, pp. 1369-1378.
Marchese, A. J. and Dryer, F. L. (1997). The Effect of Non-Luminous Thermal Radiation in Microgravity Droplet Combustion. Combust. Sci. and Tech., 124, 1-6, pp. 371-402.
Marchese, A. J., Dryer, F. L. and Nayagam, V. (1998). Microgravity Experiments and Detailed Modeling of n-Alkane Droplet Combustion. Work-in-Progress Poster Session. Twenty-Seventh Symposium (International) on Combustion, Boulder, CO.
Marchese, A. J. and Dryer, F. L. (1998). Detailed Numerical Modeling of Liquid Droplet Combustion Experiments Conducted Aboard Microgravity Science Laboratory-1. 36th Annual Aerospace Sciences Meeting, Reno, NV, Jan. 1998.
Marchese, A. J. (1997) Microgravity Droplet Combustion. Invited Lecture: University of Delaware Fluid, Particulate and Environmental Seminar Series, Oct. 1997.
Marchese, A. J. and Dryer, F. L. (1997). Detailed Kinetic Modeling of Microgravity N-Alkane Droplet Flames. Eastern States Meeting of the Combustion Institute, Hartford, CT, Oct. 1997.
Marchese, A. J. and Dryer, F. L. (1997). Science Support for Space-Based Droplet Combustion: Drop Tower Experiments and Numerical Modeling. NASA CP-10194, Fourth International Microgravity Combus-tion Workshop, NASA Lewis Research Center, Cleveland, OH, May, 1997.
Marchese, A.J. and Dryer, F.L. "Radiative Effects in Space-Based Methanol/Water Droplet Combustion Experiments", Presented at the Eastern States Sectional Meeting of the Combustion Institute, Hilton Head, SC, December 1996.
Lee, J.C., Marchese, A.J., Tomboulides, A.G., Yetter, R.A., and Dryer, F.L. "Droplet Combusiton in a Low Reynolds Number Environment", Presented at the Eastern States Sectional Meeting of the Combustion Institute, Hilton Head, SC, December 1996.
Marchese, A. J. and Dryer, F. L., "The Effect of Non-Luminous Gas Phase Radiation on the Combustion of Large Droplets in Microgravity" , Presented at the Work-In-Progress Poster Session, Twenty-Sixth Symposium (International) on Combustion, Naples, Italy, July, 1996.
Marchese, A. J., Dryer, F. L., Vedha-Nayagam, M., and Colantonio, R., "Microgravity Combustion of Methanol and Methanol/Water Droplets: Drop Tower Experiments and Numerical Modeling", Twenty-Sixth Symposium (International) on Combustion, Pittsburgh, PA, 1996, p. 1209.
Marchese, A. J., Dryer, F. L., Vedha-Nayagam, M., and Colantonio, R., "Hydroxyl Radical Chemiluminescence Imaging and the Structure of Microgravity Droplet Flames", Twenty-Sixth Symposium (International) on Combustion, Pittsburgh, PA , 1996, p. 1219.
Marchese, A. J. and Dryer, F. L., "The Effect of Liquid Mass Transport on the Combustion and Extinction of BiComponent Liquid Droplets of Methanol and Water", Combustion and Flame, 105:104-122 (1996).
Marchese, A. J., Lee, J. C., Held, T.J. and Dryer, F. L., "The Effect of Detailed Chemistry and Transport on Microgravity Droplet Combustion", Third International Microgravity Combustion Workshop, Cleveland, OH, April 1995.
Marchese, A.J., and Dryer, F. L., "Transient Numerical Modeling of the Microgravity Combustion of Bi-Component Liquid Droplets: Heptane/ Hexadecane Mixtures", Western States/Central States/Mexican National Sectional Meeting of the Combustion Institute, San Antonio, TX, April 1995.
Marchese, A.J., and Dryer, F. L., "Transient Numerical Modeling of the Microgravity Combustion of Bi-Component Liquid Droplets: Methanol/ Water Mixtures", Eastern States Sectional Meeting of the Combustion Institute, Clearwater, FL, December 1994.
Marchese, A.J., and Dryer, F. L., "Computational Modeling of Methanol Droplet Vaporization", Eastern States Sectional Meeting of the Combustion Institute, Princeton, NJ, October, 1993.