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<div><span class="x_elementToProof" style="font-size: 12pt; font-family: Calibri, Arial, Helvetica, sans-serif; margin: 0px; color: rgb(0, 0, 0); background-color: rgb(255, 255, 255);"><span class="x_x_x_elementToProof" style="margin: 0px; background-color: rgb(255, 255, 255);"><span class="x_x_x_ContentPasted1 x_x_x_ContentPasted0 x_x_ContentPasted0 x_ContentPasted0" style="margin: 0px; display: inline !important; background-color: rgb(255, 255, 255);">Hello
Everyone,</span></span></span></div>
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I am currently working on setting up a MHD problem in the r-z geometry with uniform grid using FLASH 4.7. My current goal is to keep the x_max boundary values fixed to their initial values throughout the simulation. To achieve this, I have modified the<span class="x_x_x_ContentPasted1 x_x_x_ContentPasted0 x_x_ContentPasted0 x_ContentPasted0" style="margin:0px"> </span><i class="x_x_x_ContentPasted1 x_x_x_ContentPasted0 x_x_ContentPasted0 x_ContentPasted0">Grid_bcApplyToRegionSpecialized.F90</i><span class="x_x_x_ContentPasted1 x_x_x_ContentPasted0 x_x_ContentPasted0 x_ContentPasted0" style="margin:0px"> </span>file
in a similar way to the Shu Osher problem. However, I have noticed that the boundary values still vary with time.</div>
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To investigate this issue, I ran the Shu-Osher problem for longer than 1.8s, which is sufficient time for the shock front to reach the x_max boundary. Interestingly, I observed that the boundary values also changed for this simulation. I have attached snapshots
of the Density vs X plot for the Shu Osher problem at 1.8s (as shown in the user manual) and at 2.4s, where the boundary value differs from the initial value.</div>
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I would greatly appreciate any guidance on setting up a fixed value boundary condition for the MHD simulation. <span class="x_x_x_ContentPasted2 x_x_x_ContentPasted0 x_x_ContentPasted0 x_ContentPasted0" style="margin: 0px; display: inline !important; background-color: rgb(255, 255, 255);">Additionally,
could you recommend a reference that describes how general type of boundary conditions (such as Newman, Dirichlet, etc.) for all primitive variables are set up in FLASH for the MHD simulation?</span></div>
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<span class="x_x_x_ContentPasted1 x_x_x_ContentPasted0 x_x_ContentPasted0 x_ContentPasted0" style="margin: 0px; display: inline !important; background-color: rgb(255, 255, 255);">Thank you in advance for your help.</span><br class="x_x_x_ContentPasted1 x_x_x_ContentPasted0 x_x_ContentPasted0 x_ContentPasted0" style="background-color: rgb(255, 255, 255);">
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<span class="x_x_x_ContentPasted1 x_x_x_ContentPasted0 x_x_ContentPasted0 x_ContentPasted0" style="margin: 0px; display: inline !important; background-color: rgb(255, 255, 255);">Nishka Sheth </span><br class="x_x_x_ContentPasted1 x_x_x_ContentPasted0 x_x_ContentPasted0 x_ContentPasted0" style="background-color: rgb(255, 255, 255);">
<span class="x_x_x_ContentPasted1 x_x_x_ContentPasted0 x_x_ContentPasted0 x_ContentPasted0" style="margin: 0px; display: inline !important; background-color: rgb(255, 255, 255);">Physics Graduate Student</span><br class="x_x_x_ContentPasted1 x_x_x_ContentPasted0 x_x_ContentPasted0 x_ContentPasted0" style="background-color: rgb(255, 255, 255);">
<span class="x_x_x_ContentPasted1 x_x_x_ContentPasted0 x_x_ContentPasted0 x_ContentPasted0" style="margin: 0px; display: inline !important; background-color: rgb(255, 255, 255);">University of Saskatchewan, Canada</span><br class="x_x_x_ContentPasted1 x_x_x_ContentPasted0 x_x_ContentPasted0 x_ContentPasted0" style="background-color: rgb(255, 255, 255);">
<span class="x_x_x_ContentPasted1 x_x_x_ContentPasted0 x_x_ContentPasted0 x_ContentPasted0" style="margin: 0px; display: inline !important; background-color: rgb(255, 255, 255);">phc027@usask.ca</span></div>
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