*HEADING Gas structure interaction with structure modeled using C3D10M elements. This test verifies the coupling between cavity fluid pressure and deformation of the structure enclosing the fluid cavity. The deformation of the structure should change the fluid pressure according to the fluid behavior definition and the pressure should get transferred to the structure. Fluid cavity pressure x Area of any face of the structure = Sum of RF in a direction normal to the selected face on all the nodes constituting that face. *NODE, NSET=NALL 1, 0., 2., 2. 2, 1., 1., 3. 3, 2., 2., 2. 4, 1., 1., 2. 5, 0., 2., 0. 6, 1., 1., -1. 7, 0., 0., 0. 8, 1., 1., 0. 9, 2., 2., 0. 10, 2., 0., 0. 11, 0., 0., 2. 12, 2., 0., 2. 13, 3., 1., 1. 14, 2., 1., 1. 15, -1., 1., 1. 16, 0., 1., 1. 17, 1., 3., 1. 18, 1., 2., 1. 19, 1., -1., 1. 20, 1., 0., 1. 21, 1., 1., 2.5 22, 0.5, 1.5, 2.5 23, 0.5, 1.5, 2. 24, 1., 2., 2. 25, 1.5, 1.5, 2. 26, 1.5, 1.5, 2.5 27, 1., 1., -0.5 28, 0.5, 1.5, -0.5 29, 0.5, 1.5, 0. 30, 0., 1., 0. 31, 0.5, 0.5, 0. 32, 0.5, 0.5, -0.5 33, 1.5, 1.5, 0. 34, 1.5, 1.5, -0.5 35, 2., 1., 0. 36, 1.5, 0.5, -0.5 37, 1.5, 0.5, 0. 38, 0.5, 0.5, 2. 39, 0.5, 0.5, 2.5 40, 1., 0., 2. 41, 1.5, 0.5, 2.5 42, 1.5, 0.5, 2. 43, 0., 1., 2. 44, 1., 2., 0. 45, 2.5, 1., 1. 46, 2.5, 0.5, 0.5 47, 2., 0.5, 0.5 48, 2., 0., 1. 49, 2., 0.5, 1.5 50, 2.5, 0.5, 1.5 51, -0.5, 1., 1. 52, -0.5, 0.5, 0.5 53, 0., 0.5, 0.5 54, 0., 1.5, 0.5 55, -0.5, 1.5, 0.5 56, 0., 0.5, 1.5 57, -0.5, 0.5, 1.5 58, -0.5, 1.5, 1.5 59, 0., 1.5, 1.5 60, 2., 1.5, 0.5 61, 2.5, 1.5, 0.5 62, 2., 2., 1. 63, 2.5, 1.5, 1.5 64, 2., 1.5, 1.5 65, 0., 0., 1. 66, 1., 2.5, 1. 67, 1.5, 2.5, 0.5 68, 1.5, 2., 0.5 69, 1.5, 2., 1.5 70, 1.5, 2.5, 1.5 71, 1., -0.5, 1. 72, 1.5, -0.5, 0.5 73, 1.5, 0., 0.5 74, 1., 0., 0. 75, 0.5, 0., 0.5 76, 0.5, -0.5, 0.5 77, 0.5, -0.5, 1.5 78, 0.5, 0., 1.5 79, 1.5, 0., 1.5 80, 1.5, -0.5, 1.5 81, 0.5, 2., 0.5 82, 0.5, 2.5, 0.5 83, 0., 2., 1. 84, 0.5, 2.5, 1.5 85, 0.5, 2., 1.5 86, 2., 1., 2. ** ** Cavity reference node ** *NODE, NSET=CAVREF 99, 1, 1, 1 *ELEMENT, TYPE=C3D10M, ELSET=ELALL 1, 4, 1, 2, 3, 23, 22, 21, 25, 24, 26 2, 8, 5, 6, 7, 29, 28, 27, 31, 30, 32 3, 6, 9, 8, 10, 34, 33, 27, 36, 35, 37 4, 2, 11, 4, 12, 39, 38, 21, 41, 40, 42 5, 2, 4, 11, 1, 21, 38, 39, 22, 23, 43 6, 8, 9, 6, 5, 33, 34, 27, 29, 44, 28 7, 14, 10, 13, 12, 47, 46, 45, 49, 48, 50 8, 16, 7, 15, 5, 53, 52, 51, 54, 30, 55 9, 15, 11, 16, 1, 57, 56, 51, 58, 43, 59 10, 13, 9, 14, 3, 61, 60, 45, 63, 62, 64 11, 13, 14, 9, 10, 45, 60, 61, 46, 47, 35 12, 11, 15, 16, 7, 57, 51, 56, 65, 52, 53 13, 18, 9, 17, 3, 68, 67, 66, 69, 62, 70 14, 20, 10, 19, 7, 73, 72, 71, 75, 74, 76 15, 20, 11, 19, 12, 78, 77, 71, 79, 40, 80 16, 17, 5, 18, 1, 82, 81, 66, 84, 83, 85 17, 17, 18, 5, 9, 66, 81, 82, 67, 68, 44 18, 12, 19, 20, 10, 80, 71, 79, 48, 72, 73 19, 7, 6, 8, 10, 32, 27, 31, 74, 36, 37 20, 3, 2, 4, 12, 26, 21, 25, 86, 41, 42 21, 5, 15, 16, 1, 55, 51, 54, 83, 58, 59 22, 20, 7, 19, 11, 75, 76, 71, 78, 65, 77 23, 13, 14, 12, 3, 45, 49, 50, 63, 64, 86 24, 3, 17, 18, 1, 70, 66, 69, 24, 84, 85 *SOLID SECTION, ELSET=ELALL, MATERIAL=MAT 0.2, *NSET, NSET=DISP_BC 1, 3, 5, 9, 17, 18, 24, 44, 62, 66, 67, 68, 69, 70, 81, 82 83, 84, 85 *NSET, NSET=FIX_BC 2, 4, 6, 7, 8, 10, 11, 12, 13, 14, 15, 16 19, 20, 21, 22, 23, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34 35, 36, 37, 38, 39, 40, 41, 42, 43, 45, 46, 47, 48, 49, 50 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 63, 64, 65, 71 72, 73, 74, 75, 76, 77, 78, 79, 80, 86 *NSET, NSET=QA_TEST_RF 1, 3, 5, 9, 83, 24, 62, 44, 18, 81, 85, 68, 69 ** **Create element sets to define fluid cavity surface ** *ELSET, ELSET=CAVITY_SURF1 1, 2, 6, 7, 8, 13, 14, 15, 22 *ELSET, ELSET=CAVITY_SURF2 3, 4, 5, 9, 10, 11, 16, 17, 23 *ELSET, ELSET=CAVITY_SURF3 12, 18, 19, 20, 21, 24 *SURFACE, TYPE=ELEMENT, NAME=CAVSURF CAVITY_SURF1, S2 CAVITY_SURF2, S3 CAVITY_SURF3, S4 ** **Material definition ** *MATERIAL, NAME=MAT *DENSITY 5000., *ELASTIC 2e-10, 0.3 ** ** Boundary consitions ** ** Type: Displacement/Rotation *Boundary FIX_BC, 1, 3 DISP_BC, 1, 3 *PHYSICAL CONSTANTS, ABSOLUTE ZERO=-273.16, UNIVERSAL GAS CONSTANT=8.314 ** **Fluid cavity definition ** *FLUID CAVITY, NAME=CAVITY, REF NODE=CAVREF, BEHAVIOR=AIR, SURFACE=CAVSURF, AMBIENT PRESSURE=1E5 *FLUID BEHAVIOR, NAME=AIR *MOLECULAR WEIGHT 0.0289 *CAPACITY, TYPE=POLYNOMIAL 28.110, 1.967E-3, 4.802E-6, -1.966E-9, 0.0 *NSET, NSET=QA_TEST_CAVREF CAVREF *INITIAL CONDITIONS, TYPE=TEMPERATURE CAVREF, 20 *INITIAL CONDITIONS, TYPE=FLUID PRESSURE CAVREF, 4E5 *AMPLITUDE, NAME=RAMP 0, 0, 1, 1 **============================================================================= **Step 1: Apply displacement BC of 0.50 to all the nodes of the face with ** normal in +2 direction. ** CVOL (at the end of step) = 10 ** PCAV (at the end of step) = 3.2E5 ** Area of the face with normal in +2 direction = 2*2 = 4 ** Sum of RF2 on the nodes of the face with normal in +2 direction = ** PCAV*4 **============================================================================= *STEP *DYNAMIC, EXPLICIT, DIRECT USER CONTROL 0.01, 1 *BOUNDARY, OP=MOD, AMPLITUDE=RAMP DISP_BC, 2, 2, 0.50 *OUTPUT, HISTORY, TIME INTERVAL=0.25 *NODE OUTPUT, NSET=QA_TEST_CAVREF PCAV, CVOL *NODE OUTPUT, NSET=DISP_BC U2 *NODE OUTPUT, NSET=QA_TEST_RF RF2 *END STEP **============================================================================= **Step 2: Apply displacement BC of -0.50 to all the nodes of the face ** with normal in +2 direction. ** All the parameters e.g. CVOL, PCAV, RF's at the end of this step ** will be the same as at the beginning of Step 1. **============================================================================= *STEP *DYNAMIC, EXPLICIT, DIRECT USER CONTROL 0.01, 1 *BOUNDARY, OP=MOD, AMPLITUDE=RAMP DISP_BC, 2, 2, -0.50 *END STEP