Numerical Study of Inclination Effect of the Floating Solar Still Fitted with a Baffle in 3D Double Diffusive Natural Convection
2. Physical Model and Governing Equations
2.1. Physical Model
2.2. Governing Equations, Assymtions, and Boundary Conditions
- Concentration and temperature: , .
- Velocity: on all walls.
- Vorticity and vector potential:
- Vector potential: at and 1, at and 1, at and 1.
3. Numerical Method, Validation, and Grid Sensitivity
3.1. Numerical Method
- Step 1: Initializing;
- Step 2: Resolution of the energy equation;
- Step 3: Resolution of the concentration equation
- Step 4: Resolution of the vorticity equation;
- Step 5: Resolution of the potential vector equation.
3.3. Grid Sensitivity
4. Results and Discussion
4.1. Flow Structure, Iso-Temperatures, and Iso-Concentrations
4.2. Heat and Masse Transfer Rates
4.3. Sensitivity Analysis
- Uncooled air-vapor leakage was observed during tilting for the solar still equipped with a small flat baffle (reference case) at the cooling zone.
- The triangular and curvilinear baffle design assisted the air-vapor mixture to cool down before the exit.
- When Ra = 2 × 104 and θ = 0°, from N = 0.5, the average heat transfer rate is highest in case 2, for triangular baffle. A 12% improvement in the average heat transfer rate compared to the reference case is observed.
- When Ra = 5 × 104 and N = 0, an improvement of the air-vapor convection is observed in the heating zone for all the new baffles designs studied at θ = 15°. The thermal gradient is enhanced in the cooling zone mainly in the middle of the cold surfaces for cases 2 and 3. When the inclination is less than 18°, all cases studied have higher average Nusselt values than the reference case. And case 2 has higher values of average heat transfer rate. For cases 2 and 3, triangular and curvilinear baffle design, the evolution is parabolic with a maximum of the average transfer rate observed for θ = 5°. In the range of angles between 5° and 20°, case 2 has the highest average mass transfer rate.
- When Ra = 5 × 104 and N = 1, the heat transfer rate for cases 1, 2, and 3 is higher than the reference case only when θ is lower than 5°. Cases 2 and 3 exhibit higher average Sherwood values than the reference case from θ = 12°. Increasing the angle from 0° to 25° exhibits for case 2 an increase in the average mass transfer rate of 35%.
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
|D||Mass diffusivity (m2/s)|
|K||Thermal conductivity (W/m·K)|
|H||Height from the base surface to the top (m)|
|L||Baffle width (m)|
|T||Dimensionless time (=)|
|Dimensionless velocity vector (=)|
|Thermal diffusivity (m2/s)|
|Coefficient of thermal expansion (K−1)|
|Coefficient of solutal expansion (K−1)|
|Dynamic viscosity (kg/m.s)|
|Kinematics viscosity (m2/s)|
|Dimensionless vector potential ()|
|Dimensionless vorticity (=)|
|Θ||Angle of inclination of still|
|x, y, z||Cartesian coordinates|
- Ghachem, K.; Kolsi, L.; Mâatki, C.; Hussein, A.K.; Borjini, M.N. Numerical simulation of three-dimensional double diffusive free convection flow and irreversibility studies in a solar distiller. Int. Commun. Heat Mass Transf. 2012, 39, 869–876. [Google Scholar] [CrossRef]
- Sathyamurthy, R.; Harris Samuel, D.G.; Nagarajan, P.K.; Arunkumar, T. Geometrical variations in solar stills for improving the fresh water yield—A review. Desalination Water Treat. 2016, 57, 1944–3986. [Google Scholar] [CrossRef]
- Rahbar, N.; Asadi, A.; Fotouhi-Bafghi, E. Performance evaluation of two solar stills of different geometries: Tubular versus triangular: Experimental study, numerical simulation, and second law analysis. Desalination 2018, 443, 44–55. [Google Scholar] [CrossRef]
- Al-Madhhachi, H.; Smaisim, G.F. Experimental and numerical investigations with environmental impacts of affordable square pyramid solar still. Sol. Energy 2021, 216, 303–314. [Google Scholar] [CrossRef]
- Moussa, R.R.; Hatem, T.M. Estimating the potential of desalinate seawater using solar glass pyramid (SGP) in hot arid zones. Clean. Eng. Technol. 2021, 4, 100189. [Google Scholar] [CrossRef]
- Kabeel, A.E.; Abdelgaied, M. Enhancement of pyramid-shaped solar stills performance using a high thermal conductivity absorber plate and cooling the glass cover. Renew. Energy 2020, 146, 769–775. [Google Scholar] [CrossRef]
- Xiong, J.; Xie, G.; Zheng, H. Experimental and numerical study on a new multi-effect solar still with enhanced condensation surface. Energy Convers. Manag. 2013, 73, 176–185. [Google Scholar] [CrossRef]
- Dev, R.; Tiwari, G.N. Characteristic equation of a passive solar still. Desalination 2009, 245, 246–265. [Google Scholar] [CrossRef]
- Sebastian, G.; Shah, A.; Thomas, S. The effect of vapour space temperature on the productivity of a passive solar still integrated with multi-functional floating absorber. J. Water Process Eng. 2021, 44, 102349. [Google Scholar] [CrossRef]
- Kaushal, A.K.; Mittal, M.K.; Gangacharyulu, D. An experimental study of floating wick basin types vertical multiple effect diffusion solar still with waste heat recovery. Desalination 2017, 414, 35–45. [Google Scholar] [CrossRef]
- Ni, G.; Zandavi, S.H.; Javid, S.M.; Boriskina, S.V.; Cooper, T.A.; Chen, G. A Salt-Rejecting Floating Solar Still for Low-Cost Desalination. Energy Environ. Sci. 2018, 11, 1510. [Google Scholar] [CrossRef]
- Wang, Q.; Zhu, Z.; Zheng, H. Investigation of a floating solar desalination film. Desalination 2018, 447, 43–54. [Google Scholar] [CrossRef]
- Chen, S.; Zhao, P.; Xie, G.; Wei, Y.; Lyu, Y.; Zhang, Y.; Yan, T.; Zhang, T. A floating solar still inspired by continuous root water intake. Desalination 2021, 512, 115133. [Google Scholar] [CrossRef]
- Alvarado-Juárez, R.; Álvarez, G.; Xamán, J.; Hernández-López, I. Numerical study of conjugate heat and mass transfer in a solar still device. Desalination 2013, 325, 84–94. [Google Scholar] [CrossRef]
- Alvarado-Juárez, R.; Xamán, J.; Álvarez, G.; Hernández-López, I. Numerical study of heat and mass transfer in a solar still device: Effect of the glass cover. Desalination 2015, 359, 200–211. [Google Scholar] [CrossRef]
- Ghachem, K.; Maatki, C.; Kolsi, L.; Alshammari, N.; Oztop, H.F.; Borjini, M.N.; Ben, A.H.; Al-Salem, K. Numerical study of heat and mass transfer optimization in a 3-d inclined solar distiller. Therm. Sci. 2017, 21, 2469–2480. [Google Scholar] [CrossRef]
- Maatki, C. Heat transfer enhancement using CNT-water nanofluids and two stages of seawater supply in the triangular solar still. Case Stud. Therm. Eng. 2022, 30, 101753. [Google Scholar] [CrossRef]
- Subhani, S.; Kumar, R.S. Numerical investigation on influence of mounting baffles in solar stills. In Proceedings of the AIP Conference Proceedings, Tamil Nadu, India, 14–15 March 2019; Volume 2161, p. 020025. [Google Scholar] [CrossRef]
- Edalatpour, M.; Kianifar, A.; Ghiami, S. Effect of blade installation on heat transfer and fluid flow within a single slope solar still. Int. Commun. Heat Mass Transf. 2015, 66, 63–70. [Google Scholar] [CrossRef]
- Serradj, D.B.; Anderson, T.N.; Nates, R.J. The use of passive baffles to increase the yield of a single slope solar still. Sol. Energy 2021, 226, 297–308. [Google Scholar] [CrossRef]
- Maatki, C. Three-Dimensional Numerical Study of the Effect of Protective Barrier on the Dispersion of the Contaminant in a Building. Mathematics 2021, 9, 1125. [Google Scholar] [CrossRef]
- Patankar, S.V. Numerical Heat Transfer and Fluid Flow; Taylor & Francis: Philadelphia, PA, USA, 1981. [Google Scholar]
- Ghachem, K.; Hassen, W.; Maatki, C.; Kolsi, L.; Al-Rashed, A.A.; Naceur, M. Numerical simulation of 3D natural convection and entropy generation in a cubic cavity equipped with an adiabatic baffle. Int. J. Heat Technol. 2018, 36, 1047–1054. [Google Scholar] [CrossRef]
- Rahman, M.M.; Öztop, H.F.; Ahsan, A.; Kalam, M.A.; Varol, Y. Double-diffusive natural convection in a triangular solar collector. Int. Commun. Heat Mass Transf. 2012, 39, 264–269. [Google Scholar] [CrossRef]
|Mesh Size||Shav||Percentage Increase||Incremental Increase|
Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.
© 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).
Almeshaal, M.A.; Maatki, C. Numerical Study of Inclination Effect of the Floating Solar Still Fitted with a Baffle in 3D Double Diffusive Natural Convection. Processes 2022, 10, 1607. https://doi.org/10.3390/pr10081607
Almeshaal MA, Maatki C. Numerical Study of Inclination Effect of the Floating Solar Still Fitted with a Baffle in 3D Double Diffusive Natural Convection. Processes. 2022; 10(8):1607. https://doi.org/10.3390/pr10081607Chicago/Turabian Style
Almeshaal, Mohammed A., and Chemseddine Maatki. 2022. "Numerical Study of Inclination Effect of the Floating Solar Still Fitted with a Baffle in 3D Double Diffusive Natural Convection" Processes 10, no. 8: 1607. https://doi.org/10.3390/pr10081607