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tfrictional model verified - sphere - GPU-based 3D discrete element method algo… |
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git clone git://src.adamsgaard.dk/sphere |
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Log |
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LICENSE |
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--- |
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commit 5dfe62b3e9c41649433d64737c1c27459b567940 |
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parent 22e628495585c3145e362c918c9e62dab291a147 |
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Author: Anders Damsgaard <[email protected]> |
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Date: Fri, 20 Jun 2014 13:16:59 +0200 |
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frictional model verified |
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Diffstat: |
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M src/contactmodels.cuh | 2 +- |
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M tests/contactmodel.py | 22 +++++++++++++--------- |
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2 files changed, 14 insertions(+), 10 deletions(-) |
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--- |
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diff --git a/src/contactmodels.cuh b/src/contactmodels.cuh |
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t@@ -454,7 +454,7 @@ __device__ void contactLinear(Float3* F, Float3* T, |
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// The energy lost from the tangential spring is dissipated as heat |
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//*es_dot += -dot(vel_t_ab, f_t); |
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//*es_dot += length(delta_t0 - delta_t) * devC_params.k_t / devC_d… |
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- *es_dot += length(length(f_t) * vel_t * devC_dt) / devC_dt; // See… |
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+ *es_dot += 0.5*length(length(f_t) * vel_t * devC_dt) / devC_dt; //… |
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//*es_dot += fabs(dot(delta_t0 - delta_t, f_t)) / devC_dt; |
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} //else { // Static case |
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diff --git a/tests/contactmodel.py b/tests/contactmodel.py |
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t@@ -153,11 +153,12 @@ orig.initTemporal(total = 0.1, file_dt = 0.01) |
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orig.run(verbose=False) |
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after.readlast(verbose=False) |
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-print(after.es) |
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+pytestutils.test((after.angvel[:,1] < 0.0).all(), |
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+ "Oblique normal collision (1/5):") |
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pytestutils.compareFloats(orig.totalKineticEnergy(), |
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after.totalKineticEnergy() |
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- + after.totalRotationalEnergy(),\ |
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- "Oblique normal collision (1/4):", tolerance=0.05) |
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+ + after.totalRotationalEnergy(), |
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+ "Oblique normal collision (2/5):", tolerance=0.05) |
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# Normal impact, low angle, slip |
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orig = sphere.sim(np=2, sid='contactmodeltest') |
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t@@ -169,16 +170,19 @@ orig.x[0,:] = [5.0, 5.0, 2.0] |
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orig.x[1,:] = [5.0, 5.0, 4.05] |
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orig.vel[0,2] = 1 |
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orig.vel[0,0] = 1 |
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-orig.mu_s[0] = 0.0 |
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-orig.mu_d[0] = 0.0 |
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+orig.mu_s[0] = 0.3 |
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+orig.mu_d[0] = 0.3 |
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orig.defineWorldBoundaries(L=[10,10,10]) |
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orig.initTemporal(total = 0.1, file_dt = 0.01) |
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orig.run(verbose=False) |
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after.readlast(verbose=False) |
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-print(after.es) |
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pytestutils.compareFloats(orig.totalKineticEnergy(), |
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after.totalKineticEnergy() |
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- + after.totalRotationalEnergy(),\ |
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- "Oblique normal collision (2/4):", tolerance=0.05) |
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- |
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+ + after.totalRotationalEnergy() |
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+ + after.totalFrictionalEnergy(), |
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+ "Oblique normal collision (3/5):", tolerance=0.05) |
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+pytestutils.test((after.angvel[:,1] < 0.0).all(), |
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+ "Oblique normal collision (4/5):") |
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+pytestutils.test(after.totalFrictionalEnergy() > 0.0, |
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+ "Oblique normal collision (5/5):") |
