Research Article
Modeling the Influence of Raleigh Numbers on Thermal and Fluidic Behaviors in a Trapezoid-shaped Cell
Issue:
Volume 13, Issue 5, October 2024
Pages:
64-72
Received:
25 September 2024
Accepted:
28 October 2024
Published:
28 November 2024
DOI:
10.11648/j.ajmp.20241305.11
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Abstract: We model the influence of Raleigh numbers in a trapezoidal cavity. One wall among the sloping walls is exposed to a heat flux density Q=100 W/ m2 and the other inclined wall is kept adiabatic. The temperature of the two horizontal walls is assumed to be constant such that Tsup=305K is greater than Tinf=300K. The equations of heat and mass transfer which direct our template are described by the Navier-Stockes equation. These equations are discretized using the finite difference method and solved by the Thomas and Gauss-Seidel algorithms. Thus, we analyze the effects of the Raleigh numbers (Ra) on temperature profiles T = 303.15 K and speeds v = 0 m/s. For a variation of Ra=103-105, we note that the convective exchanges of the confined air and the different walls become preponderant with the increase in the Rayleigh number. Also, we contact that the speed of the confined air remains high along the horizontal walls for a Ra high number, but low near the inclined walls. These results show the effects of natural convection in this trapezoidal cavity.
Abstract: We model the influence of Raleigh numbers in a trapezoidal cavity. One wall among the sloping walls is exposed to a heat flux density Q=100 W/ m2 and the other inclined wall is kept adiabatic. The temperature of the two horizontal walls is assumed to be constant such that Tsup=305K is greater than Tinf=300K. The equations of heat and mass transfer ...
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Research Article
Molecular Orientation Resolved (e, 2e) Cross Sections for CF4 at 67 eV Impact Energy
Khokon Hossen*
,
Humaira Takia,
Hossain Mohammad Arshad,
Rahman Moshiur,
Md. Bellal Hossain,
Muhammad Masudur Rahaman
Issue:
Volume 13, Issue 5, October 2024
Pages:
73-78
Received:
20 October 2024
Accepted:
8 November 2024
Published:
28 November 2024
DOI:
10.11648/j.ajmp.20241305.12
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Abstract: In this investigation, the fully differential cross sections (FDCS) for ionization of electron impact at low energy (E0 = 67 eV) were measured for the specific orientations of the molecules and around it axis. In the full perpendicular plane (FPP), the FDCS for CF4 were experimentally figured out by using reaction microscope (REMI) for different kinematics such as two ejection electron energies of 5 eV and 8 eV, scattering angles of -25° and 30°, and two molecular axis directions of ϕMol = 0° and 45°, also their relative orientations such as 180° and 225°. The momentum vectors of the two ejected electrons (with energies Ee1, and Ee2) and the fragment ions (e, 2e+ ions) were detected by the triple coincidence method. For the duration of dissociation, the time of flight (TOF) of CF3+, CF2+, CF+, F+, and C+ are observed in the TOF diagram. During the dissociation of the final fragment of CF3+ ion and its electronic ground state neutral F, the momentum vector of CF3+ allows us to draw conclusions about the orientation of the molecule in the course of the collision. Finally, it was remarked that concerning molecular orientation, electrons are highly sensitive at low energy and low scattering angle.
Abstract: In this investigation, the fully differential cross sections (FDCS) for ionization of electron impact at low energy (E0 = 67 eV) were measured for the specific orientations of the molecules and around it axis. In the full perpendicular plane (FPP), the FDCS for CF4 were experimentally figured out by using reaction microscope (REMI) for different ki...
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