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A spherical is meshed by many little triangles. A time-dependent pressure (p=10*t) is equally applied to the inner surface of a spherical in the normal direction all the time. After t1=0.1s, the spherical is broken, and each little triangle is disconnected.

Assuming during t1, p is constantly 1 (10*0.1). My ultimate goal is to calculate the energy brought by p to this system

My idea is to use p*area*displacement for 1 triangle, then do the same thing for all other triangles

Here is what I have from the simulation (for one triangle).

Nodal coordinates (vector in x,y,z) for three vertices of the triangle

p1: 2.48309 2.51276 2.45388

p2: 2.4875 2.50415 2.45103

p3: 2.47773 2.50283 2.45452

Nodal velocities (vector in x,y,z) for three vertices of the triangle

v1: -11.352 4.68846 -58.9501

v2: -10.2788 -1.54017 -60.6666

v3: 12.043 6.94501 -34.1632

Nodal displacements (vector in x,y,z) for three vertices of the triangle

d1: -0.00023 0.000131 -0.00071

d2: -0.00025 6.02E-05 -0.00066

d3: -0.00027 0.000148 -0.00066

I write the following MATLAB code to compute the area of this triangle from nodal coordinates

'''

p1=[2.48309 2.51276 2.45388];

p2=[2.4875 2.50415 2.45103];

p3=[2.47773 2.50283 2.45452];

edge12=p2-p1;

edge13=p3-p1;

area = 0.5*norm(cross(edge12,edge13),2)

'''

Then I use p*area to get the force, but I don't know how to get the right (or approximated) displacement, since force should be in the same direction as displacement, what I have is the Nodal displacements shown above.

Any idea to figure out the energy brought by p to this system during t1? It will be great if the answer is explained in detail