FullText URL | fulltext.pdf |
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Author | Ahmed, Fatma B.M.| Esmail, Mohamed F.C.| Kawahara, Nobuyuki| Tomita, Eiji| |
Keywords | Infrared absorption method CO2 HITRAN EGR Visualization Spark plug sensor |
Published Date | 2019-12-26 |
Publication Title | Ain Shams Engineering Journal |
Publisher | Elsevier |
ISSN | 20904479 |
Content Type | Journal Article |
language | English |
OAI-PMH Set | 岡山大学 |
Copyright Holders | © 2019 Ain Shams University. Production and hosting by Elsevier B.V. |
File Version | publisher |
DOI | 10.1016/j.asej.2019.12.003 |
Related Url | isVersionOf https://doi.org/10.1016/j.asej.2019.12.003 |
JaLCDOI | 10.18926/15510 |
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FullText URL | Mem_Fac_Eng_OU_25_2_39.pdf |
Author | Nsunge Felix Chintu| Tomita, Eiji| Hamamoto, Yoshisuke| |
Abstract | Velocity distributions and related parameters of transient and steady, turbulent air jets issuing under atmospheric conditions at Mach 0.14, 0.33 and 0.5 have been predicted using Navier-Stokes(N-S) equations for compressible flow and incompressible flow independently with the k-ε model. The closeness and consistence of the results predicted by the N-S equations for compressible and incompressible flows as well as with relevant measurement or similar prediction show that the incompressible flow assumption for at least some subsonic gas jets issuing at velocities higher than Mach 0.3, the general limit for incompressible fluid flow, can be reasonably accurate particularly in the main fully developed flow region. This suggests that the divergence term in source terms of the momentum, turbulence energy and its dissipation rate equations have negligible effects for some seemingly compressible high speed, subsonic free gas jets. The computation time is reduced by at least 18 % when incompressible flow assumption is used. |
Publication Title | Memoirs of the Faculty of Engineering, Okayama University |
Published Date | 1991-03-28 |
Volume | volume25 |
Issue | issue2 |
Start Page | 39 |
End Page | 54 |
ISSN | 0475-0071 |
language | English |
File Version | publisher |
NAID | 120002307456 |
JaLCDOI | 10.18926/15508 |
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FullText URL | Mem_Fac_Eng_OU_25_2_25.pdf |
Author | Nsunge Felix Chintu| Tomita, Eiji| Hamamoto, Yoshisuke| |
Abstract | A suddenly started cold methane gas jet issuing from a 1 mm diameter orifice into still air at Mach one has been predicted using the two-equation, high Reynolds number version of k-ε turbulence model and SIMPLE algorithm which employs so called primitive variables and a hybrid scheme for treating combined diffusion and convection. Global trends of predicted radial distributions of velocity, temperature, methane concentration in the steady rear part of the transient jet and axial jet tip penetration compare reasonably well with universal profiles representing measurement for the steady jet particularly in the fully developed turbulent core and semi-empirical relation for the transient jet respectively. The prediction scheme has shown reasonably good accuracy especially in prediction of main flow parameters of a transient, high speed compressible gas jet issuing into a dissimilar surrounding gas(binary gas mixture jet). |
Publication Title | Memoirs of the Faculty of Engineering, Okayama University |
Published Date | 1991-03-28 |
Volume | volume25 |
Issue | issue2 |
Start Page | 25 |
End Page | 38 |
ISSN | 0475-0071 |
language | English |
File Version | publisher |
NAID | 120002307676 |
JaLCDOI | 10.18926/15414 |
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FullText URL | Mem_Fac_Eng_OU_26_1_27.pdf |
Author | Tomita, Eiji| Nsunge Felix Chintu| Hamamoto, Yoshisuke| |
Abstract | Distributions of hydrogen gas concentration in a suddenly started, single shot hydrogen gas jet issuing from a 1 mm diameter injector into still air were measured using laser interferometry method. This unsteady, turbulent free jet flow has also been calculated using the two-equation, high Reynolds number version of k-ε turbulence model and hybrid scheme for treating combined diffusion and convection in the SIMPLE algorithm. The injection pressure was 0.5 MPa for which predicted and measured temporal jet tip penetration distributions indicate that the jet discharged into still air at Mach 0.25. The level of agreement between present prediction and measurement is good in some regions and poor in others. |
Publication Title | Memoirs of the Faculty of Engineering, Okayama University |
Published Date | 1991-11-30 |
Volume | volume26 |
Issue | issue1 |
Start Page | 27 |
End Page | 41 |
ISSN | 0475-0071 |
language | English |
File Version | publisher |
NAID | 120002307648 |