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Old   March 28, 2014, 02:06
Unhappy overset: how to improve the quality
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the picture shows the wave pattern which produced by the hull. the wave pattern in the overlaping zone is not good. the wave pattern in the overset region did not match the one in the background region.
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Old   March 28, 2014, 03:52
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make sure you are inspecting the scene at the end of a timestep and it is better to set the scene update the timestep for all unsteady scenes

you will always see some mismatch on contours with overset since there will normally be some interpolation between the regions as explained in this help topic Modeling Physics > Using Overset Meshes > Visualizing and Analyzing Solution

making the mesh finer in that area will reduce the effect
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Old   March 28, 2014, 07:07
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hello, i just simulate the flow around the body, the total resistance of the body is not expected,how should i improved the simulation, the y+ in the simulation is smaller than 100.
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Old   March 31, 2014, 04:16
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depending on the type of hull you should be able to get within 1% of measured results so you need to consider
- accuracy of measure data since this is regularly a problem
- are you comparing apples with apples ie what was the measured condition and are you replicating this
- is the hull surface accurate
- is the mesh of the surface accurately following the geometry surface ie the surface or volume mesh might need more care
- y+ should be 30-100 for scale models and can be larger for full scale hulls since it is hard to get low
- if you are doing just flat water resistance in deep water there is little need for overset
- ensure you are capturing the bow waves and wake well with good local volume mesh refinement
- related to this is then general mesh refinement to get grid independent solution
- etc etc
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Old   April 9, 2014, 23:11
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thank you .
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