Numerical computation of entropy generation in an astronautical electromagnetic swirl thermonuclear engine propulsion system

Beg, OA; Abdou, A; Beg, TA; Kadir, A; Malysheva, LI; Zubair, A; Kuharat, S; Leonard, HJ; El Gendy, M

Abstract

Nuclear propulsion is currently the only feasible option for long duration spacecraft manned missions. Many new designs have been proposed and tested including thermal nuclear rockets (which achieve at least double the propulsion efficiency of the Space Shuttle main engine), plasma fusion systems and hybrid nuclear/laser systems. Nuclear thermal propulsion, where a fission reactor heats propellants like hydrogen that are then accelerated through a nozzle, holds the potential of reducing travel times for deep space missions, such as to Mars. Although originally developed at NASA Marshall in the 1970s, recently there has been a resurging interest in nuclear propulsion vehicles. A new system has been considered which combines the vortex rocket engine designed by Orbitec with a magnetohydrodynamic nuclear propulsion system. This VCR (vapour core reactor) MHD nuclear thermal propulsion engine features swirling plasma flow to achieve enhanced efficiency. Motivated by providing a deeper appreciation of the fluid dynamics of this aspect of the propulsion system, in the current work, a multi-physical mathematical model is developed for analyzing entropy generation in magnetohydrodynamic (MHD) slip flow over a rotating disk in the VCR core propulsion system. The nonlinear partial differential equations for laminar, steady MHD flow are reduced to a system of multiple coupled nonlinear ordinary differential equations by the Von Kármán approach, which are analytically solved by applying the homotopy analysis method (HAM) with given boundary conditions. Validation is conducted with MATLAB numerical quadrature. The convergence of the obtained series solutions is examined in detail. The influence of the magnetic interaction number, the slip factor and Prandtl number on dimensionless velocity and temperature profiles is presented graphically. Furthermore, the effects of magnetic interaction number and slip factor on entropy generation are investigated. Contour visualizations of velocity contours in all directions are also presented. As the magnetic interaction parameter increases, the amount of entropy generation increases considerably (it is minimized in the absence of a magnetic field), implying that in order to control the entropy which is generated from swirling flow on the disk surface, the value of magnetic interaction parameter should be reduced. The dominant mechanism of irreversibility is due to fluid friction irreversibility. The computations find applications in optimizing fluid dynamics aspects of novel swirl nuclear thermal MHD space propulsion systems and furthermore provide an excellent benchmark for further investigations using computational fluid dynamics codes e. g. ANSYS FLUENT/MAXWELL.

Citation

Beg, O., Abdou, A., Beg, T., Kadir, A., Malysheva, L., Zubair, A., …El Gendy, M. Numerical computation of entropy generation in an astronautical electromagnetic swirl thermonuclear engine propulsion system. Presented at ICFM 2022: 16th International Conference on Fluid Mechanics, Helsinki, Finland

• Presentation Conference Type: Other
• Conference Name: ICFM 2022: 16th International Conference on Fluid Mechanics
• Conference Location: Helsinki, Finland
• End Date: Jul 20, 2022
• Acceptance Date: Dec 13, 2020
• Deposit Date: Jan 8, 2021
• Publisher URL: https://waset.org/fluid-mechanics-conference-in-july-2022-in-helsinki
• Related Public URLs: https://waset.org/
• Additional Information: Event Type : Conference