I did some google research and n, and t are normal and tangent to the boundary, for the terminology of soft fixed, hard fixed etc.
9.1.3 Boundary conditions
For the top and bottom of a rectangular plate
The following boundary conditions can be applied in the Reissner-Mindlin plate model:
• Soft fixed edge: w = 0 and θ · n = 0 D1=D2=0
• Hard fixed edge: w = 0 and θ = 0 D1=D2=D3=0
• Soft simply supported edge: w = 0 D1=0
• Hard simply supported edge: w = 0 and θ · t = 0 D1=D3=0
• Free edge: m · n = 0 and (q + T · ∇w) · n = 0
I ran an example rectangular plate case, the soft fixed and the hard fixed case had the same transverse deflection values.
Elastic plate solver for panel speaker simulation
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Re: Elastic plate solver for panel speaker simulation
Great, thanks.
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Re: Elastic plate solver for panel speaker simulation
Hi,
You're right in your analysis. If you define D1 (=u) on the BC there really is no room for its tangential derivative to be defined but setting it to zero is fine. So most often you would set both D2 (=du/dx) and D3 (=du/dy) to zero or neither since then you don't have to think how the axis is alinged vs. the BCs. With stretch of imagination I can think of some special case of joint where you define on angle when the normal derivative would be set differently than the tangential one but certainly it would not be common.
-Peter
You're right in your analysis. If you define D1 (=u) on the BC there really is no room for its tangential derivative to be defined but setting it to zero is fine. So most often you would set both D2 (=du/dx) and D3 (=du/dy) to zero or neither since then you don't have to think how the axis is alinged vs. the BCs. With stretch of imagination I can think of some special case of joint where you define on angle when the normal derivative would be set differently than the tangential one but certainly it would not be common.
-Peter