scholarly journals Rayleigh Scattering Measurement of Neutral Atom Number Density Downstream of a Hall Thruster under Cold Flow Conditions

2017 ◽  
Vol 60 (5) ◽  
pp. 327-330
Author(s):  
Masataka IWAMOTO ◽  
Naoji YAMAMOTO ◽  
Taichi MORITA ◽  
Hideki NAKASHIMA ◽  
Kentaro TOMITA ◽  
...  
Keyword(s):  
Rayleigh Scattering ◽  
Neutral Atom ◽  
Hall Thruster ◽  
Number Density ◽  
Flow Conditions ◽  
Atom Number ◽  
Cold Flow ◽  
Atom Number Density ◽  
Scattering Measurement

scholarly journals Application of Laser-Enhanced Ionization: Atomization Efficiency Determination

1992 ◽  
Vol 46 (9) ◽  
pp. 1370-1375 ◽  
Author(s):  
King-Dow Su ◽  
King-Chuen Lin ◽  
Wei-Tzou Luh
Keyword(s):  
Free Atom ◽  
Number Density ◽  
Atom Number ◽  
Metal Elements ◽  
Atomization Efficiency ◽  
Atom Number Density ◽  
Efficiency Determination

We have demonstrated that the laser-enhanced ionization (LEI) technique can be used to determine the efficiency of atomization of metal elements in an atmospheric acetylene/air flame. We have derived a useful relation between the time-integrated LEI signal and the total free atom number density in a flame. We determine the efficiency of atomization of ∼0.13–0.37 for the lithium element and of ∼1.0 for the sodium element. Our results agree well with AA measurements reported previously.

Experimental and Modeling Studies of B Atom Number Density Distributions in Hot Filament Activated B2H6/H2and B2H6/CH4/H2Gas Mixtures†

2006 ◽  
Vol 110 (9) ◽  
pp. 2868-2875 ◽  
Author(s):  
Dane W. Comerford ◽  
Andrew Cheesman ◽  
Thomas P. F. Carpenter ◽  
David M. E. Davies ◽  
Neil A. Fox ◽  
...  
Keyword(s):  
Number Density ◽  
Atom Number ◽  
Density Distributions ◽  
Modeling Studies ◽  
Atom Number Density ◽  
Hot Filament

scholarly journals Investigation of the on-axis atom number density in the supersonic gas jet under high gas backing pressure by simulation

AIP Advances ◽  
2015 ◽  
Vol 5 (10) ◽  
pp. 107220 ◽  
Author(s):  
Guanglong Chen ◽  
A. S. Boldarev ◽  
Xiaotao Geng ◽  
Yi Xu ◽  
Yunjiu Cao ◽  
...  
Keyword(s):  
Gas Jet ◽  
Number Density ◽  
Atom Number ◽  
Backing Pressure ◽  
Atom Number Density ◽  
Supersonic Gas Jet

Quantification of Gas-Phase H-Atom Number Density by Tungsten Phosphate Glass

2005 ◽  
Vol 44 (1B) ◽  
pp. 732-735 ◽  
Author(s):  
Takashi Morimoto ◽  
Hironobu Umemoto ◽  
Koji Yoneyama ◽  
Atsushi Masuda ◽  
Hideki Matsumura ◽  
...  
Keyword(s):  
Gas Phase ◽  
Phosphate Glass ◽  
Number Density ◽  
Atom Number ◽  
Atom Number Density

Numerical Studies on Trapped-Vortex Concepts for Stable Combustion

1998 ◽  
Vol 120 (1) ◽  
pp. 60-68 ◽  
Author(s):  
V. R. Katta ◽  
W. M. Roquemore
Keyword(s):  
Drag Coefficient ◽  
Reacting Flow ◽  
Flow Conditions ◽  
Third Order ◽  
Cold Flow ◽  
Flow Simulations ◽  
Numerical Studies ◽  
Dynamic Flows ◽  
Experimental Findings ◽  
Trapped Vortex

Spatially locked vortices in the cavities of a combustor aid in stabilizing the flames. On the other hand, these stationary vortices also restrict the entrainment of the main air into the cavity. For obtaining good performance characteristics in a trapped-vortex combustor, a sufficient amount of fuel and air must be injected directly into the cavity. This paper describes a numerical investigation performed to understand better the entrainment and residence-time characteristics of cavity flows for different cavity and spindle sizes. A third-order-accurate time-dependent Computational Fluid Dynamics with Chemistry (CFDC) code was used for simulating the dynamic flows associated with forebody-spindle-disk geometry. It was found from the nonreacting flow simulations that the drag coefficient decreases with cavity length and that an optimum size exists for achieving a minimum value. These observations support the earlier experimental findings of Little and Whipkey (1979). At the optimum disk location, the vortices inside the cavity and behind the disk are spatially locked. It was also found that for cavity sizes slightly larger than the optimum, even though the vortices are spatially locked, the drag coefficient increases significantly. Entrainment of the main flow was observed to be greater into the smaller-than-optimum cavities. The reacting-flow calculations indicate that the dynamic vortices developed inside the cavity with the injection of fuel and air do not shed, even though the cavity size was determined based on cold-flow conditions.

scholarly journals Investigation of the Flow In Cold Condition at the Exit of a Supersonic Combustor Test Bench

2020 ◽  
Author(s):  
Jefte da Silva Guimarães ◽  
Valéria Serrano Faillace Oliveira Leite ◽  
Dermeval Carinhana Junior ◽  
Marco Antônio Sala Minucci
Keyword(s):  
Nozzle Exit ◽  
Test Bench ◽  
Supersonic Combustion ◽  
Flow Conditions ◽  
Circular Section ◽  
Cold Flow ◽  
Ground Test ◽  
Cold Condition ◽  
Transition Piece ◽  
Generator Unit

For studies of hypersonic flows and supersonic combustion in ground test facilities, three devices can be used as ram accelerators, shock tunnels and supersonic combustor test benches. These devices can reproduce, on the ground, similar conditions to those in real flight at a certain altitude and speed. In the case of the supersonic combustor test bench (SCTB), it simulates the same flow conditions inside the combustor of a scramjet. The SCTB consists basically of a combustion chamber or vitiated air generator unit, where the air is heated, and a nozzle, where the air is accelerated to the desired test speed. The supersonic combustor to be tested is directly coupled to the nozzle exit of the SCTB. Ultimately, it was necessary to use a transition piece to connect the nozzle to the combustor to be tested, because the nozzle exit has a circular section and the combustor entrance has a rectangular one. This work aims to present the process of characterizing the cold flow along the SCTB of the Institute for Advanced Studies (IEAv) using the schlieren technique. The interference of the transition piece in obtaining the required flow conditions at the exit of the SCTB or the entrance of the combustor was mainly evaluated.

Sign in / Sign up

Export Citation Format

Share Document