Open Access
Numan Siddique Mazumder
Pradip Lingfa
Asis Giri
- Student, Department of Mechanical Engineering, North Eastern, Regional Institute of Science and Technology, Nirjuli, Arunachal Pradesh, India
- Professor, Department of Mechanical Engineering, North Eastern, Regional Institute of Science and Technology, Nirjuli, Arunachal Pradesh, India
Abstract
Ethanol is a suitable biofuel as it has fewer toxic emissions and higher-octane numbers. For spray combustion applications, the gas phase motion must be considered while numerically investigating the fundamental aspects of droplet evaporation and combustion processes. Hence, we have numerically simulated the evaporation dynamics of an isolated spherically shaped ethanol droplet under a forced convective air environment in the absence of gravity. The momentum transfer between two phases is captured by incorporating the Navier-Stokes equation into the spherical polar coordinate system. The governing equations of species, motion, and heat transfer are solved with the aid of the finite difference method. The variable blowing effect (Stefan flow), unsteady droplet heating, and non-unitary Lewis number are considered in the mathematical formulation. The Reynolds number is considered 100 at an ambient temperature of 600 K. The present work is validated by comparing the d2-curve of an ethanol droplet with the literature. A parametric study was
performed to examine the effects of droplet initial diameter and temperature. The diameter is considered in the range of 0.2 mm to 1.0 mm, while the internal temperature is varied from 290 K to 325 K. The results reveal that droplets with a smaller diameter evaporate early, and the heat-up period is less compared to the bigger droplet. Moreover, a droplet with a higher internal temperature
has a relatively shorter life span compared to one with a lower internal temperature. Also, the streamline, isotherm, and species concentration contour plots of the evaporating droplet have been shown.
Keywords: Biofuels, evaporation, Navier-Stokes equation, force-convection, diameter, internal temperature
This article belongs to Conference RAMMTE-2022: Recent Advances in Materials, Manufacturing and Thermal Engineering
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Journal of Polymer and Composites
| Volume | 10 |
| 1 | |
| Received | August 27, 2022 |
| Accepted | September 6, 2022 |
| Published | January 19, 2023 |