اﺛﺮ ﺷﻜﻞ و ﻧﺴﺒﺖ اﺑﻌﺎد دﻳﻮاره ﺑﺮ اﻧﺘﻘﺎل ﺣﺮات ﺳﻴﺎل ﻏﻴﺮﻧﻴﻮﺗﻨﻲ ﺑﺎ ﻣﺪل ﺗﻮاﻧﻲ در ﺣﻀﻮر ﻣﻴﺪان ﻣﻐﻨﺎﻃﻴﺴﻲ

The effect of wall shape and aspect ratio on heat transfer non-Newtonian power law fluid in the presence of magnetic field

در اﻳﻦ ﻣﻄﺎﻟﻌﻪ، اﺛﺮ ﻣﻴﺪان ﻣﻐﻨﺎﻃﻴﺴﻲ و ﺷﻜﻞ و ﻧﺴﺒﺖ اﺑﻌﺎد دﻳﻮاره ﻣﺤﻔﻈﻪ ﺑﺮ اﻧﺘﻘﺎل ﺣﺮارت ﺳﻴﺎل ﻏﻴﺮﻧﻴﻮﺗﻨﻲ ﺑﺎ ﻣﺪل ﺗﻮاﻧﻲ ﺑﺎ اﺳﺘﻔﺎده از روش اﺧﺘﻼف ﻣﺤﺪود ﺷﺒﻜﻪ ﺑﻮﻟﺘﺰﻣﻦ ﺑﺮرﺳﻲ ﺷﺪه اﺳﺖ. دﻳﻮاره ﺳﻤﺖ ﭼﭗ در دﻣﺎي ﺛﺎﺑﺖ ﮔﺮم ﻗﺮار دارد و دﻳﻮارهﻫﺎي ﻣﻮرد ﺑﺮرﺳﻲ ﺳﻤﺖ راﺳﺖ ﻣﺤﻔﻈﻪ در دﻣﺎي ﺛﺎﺑﺖ ﺳﺮد ﻗﺮار دارﻧﺪ. ﺳﺎﻳﺮ دﻳﻮارهﻫﺎ آدﻳﺎﺑﺎﺗﻴﻚ در ﻧﻈﺮ ﮔﺮﻓﺘﻪ ﺷﺪهاﻧﺪ. ﺗﺄﺛﻴﺮ ﻋﺪد ﻫﺎرﺗﻤﻦ، ﻣﻘﺪار ﺷﺎﺧﺺ ﺗﻮاﻧﻲ ﺳﻴﺎل ﻏﻴﺮﻧﻴﻮﺗﻨﻲ، ﻧﺴﺒﺖ اﺑﻌﺎد و ﺷﻜﻞ دﻳﻮاره ﻣﺤﻔﻈﻪ ﺑﺮ ﻣﻴﺰان اﻧﺘﻘﺎل ﺣﺮارت ﺑﺮرﺳﻲ ﺷﺪه اﺳﺖ. ﻧﺘﺎﻳﺞ ﻧﺸﺎن ﻣﻲدﻫﺪ ﻛﻪ اﻓﺰاﻳﺶ ﺷﺎﺧﺺ ﺗﻮاﻧﻲ، ﻧﺴﺒﺖ اﺑﻌﺎد و ﻋﺪد ﻫﺎرﺗﻤﻦ ﺳﺒﺐ ﻛﺎﻫﺶ ﻋﺪد ﻧﺎﺳﻠﺖ ﻣﺘﻮﺳﻂ ﻣﻲﮔﺮدد. ﻫﻤﭽﻨﻴﻦ ﻋﻤﻮﻣﺎ ﺑﻴﺸﺘﺮﻳﻦ ﻣﻴﺰان اﻧﺘﻘﺎل ﺣﺮارت ﻣﺮﺑﻮط ﺑﻪ ﺣﺎﻟﺘﻲ اﺳﺖ ﻛﻪ دﻳﻮاره ﻣﻮرب ﺑﺎﺷﺪ. ﺑﻌﻼوه اﻓﺰاﻳﺶ ﺷﺎﺧﺺ ﺗﻮاﻧﻲ ﺳﺒﺐ ﻛﺎﻫﺶ اﺛﺮ ﻣﻴﺪان ﻣﻐﻨﺎﻃﻴﺴﻲ ﻣﻲﮔﺮدد.

In this paper, the effect of shape and aspect ratio of wall on natural convection heat transfer of non-Newtonian fluid with power law model within two-dimensional enclosure in the presence of a uniform magnetic field by lattice Boltzmann method (LBM) is investigated. The left wall is at a constant hot temperature, while the right wall is kept on cold constant temperature and other walls are considered adiabatic. In this simulation, the flow field and temperature are calculated by simultaneously solving the flow and temperature distribution functions. The effect of various parameters such as Hartmann number, aspect ratio, different shape of the wall and power index of non-Newtonian fluid is investigated. The results show that increasing power index, aspect ratio and Hartmann number decrease the average Nusselt number. Also, the highest amount of heat transfer is generally associated with the case of a triangular wall. In addition, increasing the power index reduces the effect of the magnetic field.