ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • 1990-1994  (3)
  • 1
    Publication Date: 2011-08-24
    Description: Microgravity tests varying oxygen concentration and forced flow velocity have examined the importance of transport processes on flame spread over very thin solid fuels. Flame spread rates, solid phase temperature profiles and flame appearance for these tests are measured. A flame spread map is presented which indicates three distinct regions where different mechanisms control the flame spread process. In the near-quenching region (very low characteristic relative velocities) a new controlling mechanism for flame spread - oxidizer transport-limited chemical reaction - is proposed. In the near-limit, blowoff region, high opposed flow velocities impose residence time limitations on the flame spread process. A critical characteristic relative velocity line between the two near-limit regions defines conditions which result in maximum flammability both in terms of a peak flame spread rate and minimum oxygen concentration for steady burning. In the third region, away from both near-limit regions, the flame spread behavior, which can accurately be described by a thermal theory, is controlled by gas-phase conduction.
    Keywords: PROPELLANTS AND FUELS
    Type: Combustion Science and Technology (ISSN 0010-2202); p. 233-249.
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Publication Date: 2019-07-12
    Description: The heat transfer rate to a thin solid combustible from an attached diffusion flame, spreading across the surface of the combustible in a quiescent, microgravity environment, was determined from measurements made in the drop tower facility at NASA-Lewis Research Center. With first-order Arrhenius pyrolysis kinetics, the solid-phase mass and energy equations along with the measured spread rate and surface temperature profiles were used to calculate the net heat flux to the surface. Results of the measurements are compared to the numerical solution of the complete set of coupled differential equations that describes the temperature, species, and velocity fields in the gas and solid phases. The theory and experiment agree on the major qualitative features of the heat transfer. Some fundamental differences are attributed to the neglect of radiation in the theoretical model.
    Keywords: INORGANIC AND PHYSICAL CHEMISTRY
    Type: ASME, Transactions, Journal of Heat Transfer (ISSN 0022-1481); 113; 670-676
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    Publication Date: 2019-07-13
    Description: The objective of this work is to determine the effect of varying imposed radiation levels on the flame spread and burning characteristics of PMMA in low gravity. The NASA Learjet is used for these experiments; it provides an environment of 10(exp -2) g's for approximately 20 seconds. Flame spread rates are found to increase non-linearly with increased external radiant flux over the range studied. This range of imposed flux values is believed to be sufficient to compensate for the radiative loss from the flame and the surface.
    Keywords: Inorganic and Physical Chemistry
    Type: NASA-CR-202553 , NAS 1.26:202553 , E-9560 , Eastern States Section Fall Technical Meeting of the Combustion Inst.; Dec 01, 1994; Clearwater Beach, FL; United States
    Format: application/pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...