Issue 10 Volume 41 May 16, 2003

20030037175 Air Products and Chemicals, Inc., Allentown, PA
Engineering Development of Slurry Bubble Column Reactor (SBCR) Technology
2002; 58 pp.; In English
Report No.(s): DE2002-803205; No Copyright; Avail: Department of Energy Information Bridge
The major technical objectives of this program are threefold: (1) to develop the design tools and a fundamental
understanding of the fluid dynamics of a slurry bubble column reactor to maximize reactor productivity, (2) to develop the
mathematical reactor design models and gain an understanding of the hydrodynamic fundamentals under industrially relevant
process conditions, and (3) to develop an understanding of the hydrodynamics and their interaction with the chemistries
occurring in the bubble column reactor. Successful completion of these objectives will permit more efficient usage of the
reactor column and tighter design criteria, increase overall reactor efficiency, and ensure a design that leads to stable reactor
behavior when scaling up to large diameter reactors.
NTIS
Bubbles; Reactor Design; Reactor Technology; Slurries; Chemical Reactors
20030037184 Illinois Univ. at Urbana-Champaign, Urbana, IL, USA
Nanoporous Silicon Carbide for Nanoelectromechanical Systems Applications
Hossain, T.; Khan, F.; Adesida, I.; Bohn, P.; Rittenhouse, T.; Lienhard, Michael, Technical Monitor; April 2003; 17 pp.; In
English; Original contains color and black and white illustrations
Contract(s)/Grant(s): NAG3-2661; WU 708-87-23
Report No.(s): NASA/CR-2003-212198; NAS 1.26:212198; E-13801; No Copyright; Avail: CASI; A03, Hardcopy
A major goal of this project is to produce porous silicon carbide (PSiC) via an electroless process for eventual utilization
in nanoscale sensing platforms. Results in the literature have shown a variety of porous morphologies in SiC produced in
anodic cells. Therefore, predictability and reproducibility of porous structures are initial concerns. This work has concentrated
on producing morphologies of known porosity, with particular attention paid toward producing the extremely high surface
areas required for a porous flow sensor. We have conducted a parametric study of electroless etching conditions and
characteristics of the resulting physical nanostructure and also investigated the relationship between morphology and materials
properties. Further, we have investigated bulk etching of SiC using both photo-electrochemical etching and inductivelycoupled-plasma
reactive ion etching techniques.
Author
Nanostructure (Characteristics); Porous Silicon; Silicon Carbides; Nanotechnology; Crystal Morphology
20030038817 NASA Glenn Research Center, Cleveland, OH, USA
Transient Evolution of a Planar Diffusion Flame Aft of a Translating Flat Plate
Gokoglu, Suleyman A.; April 2003; 17 pp.; In English; Second Mediterranean Combustion Symposium, 6-9 Jan. 2002, Sharm
El-Sheikh, Egypt; Original contains color illustrations
Contract(s)/Grant(s): WBS 22-101-42-02
Report No.(s): NASA/TM-2003-212107; NAS 1.15:212107; E-13762; No Copyright; Avail: CASI; A03, Hardcopy
The high degree of spatial symmetry of a planar diffusion flame affords great simplifications for experimental and
modeling studies of gaseous fuel combustion. Particularly, in a microgravity environment, where buoyancy effects are
negligible, an effectively strain-rate-free, vigorous flame may be obtained. Such a flame can also provide long residence times
and large length scales for practical probing of flame structures and soot processes. This 2-D numerical study explores the
feasibility of establishing such a planar diffusion flame in an enclosed container utilizing a realistic test protocol for a
microgravity experiment. Fuel and oxygen mixtures, initially segregated into two half-volumes of a squat rectangular
container by a thin separator, are ignited as soon as a flammable mixture is formed in the wake of the separator withdrawn
in the centerplane. A triple-flame ensues that propagates behind the trailing edge of the separator. The results of calculations
show that the mechanically- and thermally-induced convection decays in about two seconds. The establishment of a planar
diffusion flame after this period seems feasible in the central region of the container with sufficient quantities of reactants left
over for subsequent studies. An analysis of the flame initiation and formation process suggests how the feasibility of creating
such a flame can be further improved.
Author
Diffusion Flames; Flat Plates; Fuel Combustion; Combustion Physics; Flame Stability; Flame Propagation
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