Swimming of Gyrotactic Microorganism in MHD Williamson nanofluid flow between rotating circular plates embedded in porous medium: Application of thermal energy storage

2021 ◽  
pp. 103511
Author(s):  
M.M. Bhatti ◽  
M.B. Arain ◽  
A. Zeeshan ◽  
R. Ellahi ◽  
M.H. Doranehgard
Keyword(s):  
Porous Medium ◽  
Energy Storage ◽  
Thermal Energy ◽  
Thermal Energy Storage ◽  
Circular Plates ◽  
Nanofluid Flow ◽  
Gyrotactic Microorganism

A Computational Analysis: A Honeycomb Flow Distributor With Porous Approximation for a Thermocline Thermal Energy Storage System

2013 ◽  
Author(s):  
Samia Afrin ◽  
Jesus D. Ortega ◽  
Vinod Kumar ◽  
Desikan Bharathan
Keyword(s):  
Porous Medium ◽  
Energy Storage ◽  
Thermal Diffusivity ◽  
Thermal Energy ◽  
Thermal Energy Storage ◽  
Computational Analysis ◽  
Perforated Plate ◽  
Flow Distribution ◽  
Heat Transfer Fluid ◽  
Mean Flow

Conversion of direct solar energy, in particular the Concentrated Solar Power (CSP) technologies, has a significant role on conventional energy cost and efficiency. A single tank thermocline Thermal Energy Storage (TES) system is accountable for the overall efficiency of this conversion system. A single tank TES system has a thermocline region that produces the temperature gradient between hot and cold storage fluid by density difference. The overall energy storage capacity depends on sustaining of this region at uniform manner. This paper analyzes how the difference in the percentage of porous medium influences the effectiveness of the flow-distribution and hence, the overall performance of the TES system. The effectiveness is assessed by the optimal flow distribution. The optimal distribution is obtained by examining the velocity profile at any horizontal plane. This plane should be uniform for sustaining the thermocline region during the operation period. To achieve a uniform velocity distribution, two symmetric perforated plate flow distributors were placed in the tank. The distributors were positioned near the inlet and outlet, and checked the performance by varying the percentage of porous medium since the distribution is influenced by the porosity. Porous distributors with hexagonal shape pore were considered and Hitec® molten salt was used as a heat transfer fluid. These respective percentages of porosity affect the flow distribution throughout the tank during the flow distribution. The standard deviations of the velocity field at different positions along z-plane and thermal diffusivity were analyzed. The analyses of our cases were done to distinguish a configuration for the minimum thermal diffusivity and velocity deviation from the mean flow. A finite volume based computational fluid dynamics software was used to execute the computational analysis.

scholarly journals Numerical modelling of phase change material melting process embedded in porous media: Effect of heat storage size

2019 ◽  
Vol 234 (3) ◽  
pp. 365-383 ◽  
Author(s):  
Pouyan Talebizadeh Sardari ◽  
Gavin S Walker ◽  
Mark Gillott ◽  
David Grant ◽  
Donald Giddings
Keyword(s):  
Heat Transfer ◽  
Heat Flux ◽  
Porous Medium ◽  
Energy Storage ◽  
Phase Change ◽  
Phase Change Material ◽  
Latent Heat ◽  
Thermal Energy ◽  
Thermal Energy Storage ◽  
Change Material

The aim of this paper is to study the influence of enclosure size in latent heat thermal energy storage systems embedded in a porous medium for domestic usage of latent heat thermal energy storage heat exchangers. A 2-D rectangular enclosure is considered as the computational domain to study the heat transfer improvement for a phase change material embedded in a copper foam considering a constant heat flux from the bottom surface. Different dimensions of the composite system are examined compared with a system without a porous medium. The thermal non-equilibrium model with enthalpy-porosity method is employed for the effects of porous medium and phase change in the governing equations, respectively. The phase change material liquid fraction, temperature, velocity, stream lines and the rate of heat transfer are studied. The presence of a porous medium increases the heat transfer significantly, but the improvement in melting performance is strongly related to the system's dimensions. For the dimensions of 200 × 100 mm (W × H), the melting time of porous-phase change material with the porosity of 95% is reduced by 17% compared with phase change material-only system. For the same storage volume and total amount of thermal energy added, the melting time is lower for the system with a lower height, especially for the phase change material-only system due to a higher area of the input heat. The non-dimensional analysis results in curve-fitting correlations between the liquid fraction and Fo.Ste.Ra −0.02 for rectangular latent heat thermal energy storage systems for both phase change material-only and composite-phase change material systems within the parameter range of 1.16 <  Ste < 37.13, 0 <  Fo < 1.5, 2.9 × 104 <  Ra < 9.5 × 108, 0 <  L f < 1 and 0 <  Fo.Ste.Ra −0.02 < 0.57. Over a range of system's volume, heat flux and surface area of the input heat flux, the benefit of composite phase change material is variable and, in some cases, is negligible compared with the phase change material-only system.

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