From: An optimal control problem for single-spot pulsed laser welding
space domain | |
radius of the cylinder Ω | 2.5 mm |
height of the cylinder Ω | 0.5 mm |
radius of the laser beam | 0.2 mm |
equation and boundary conditions | |
ambience temperature | \(\theta _{\text{amb}} = {295}\) K |
convective heat transfer coefficient | \(h = 20\ \mathrm{W}/ \mathrm{m} ^{2}\) |
radiative heat transfer coefficient | \(k = 2.26 \cdot 10^{-9}\ \mathrm{W}/ \mathrm{m} ^{2} \mathrm{K} ^{4}\) |
objective functional | |
welding penetration penalty coefficient | \(\beta _{\text{penetration}} = 10^{-2}\) |
solidification velocity penalty coefficient | \(\beta _{\text{velocity}} = 1.5 \cdot 10^{-1}\) |
welding completeness penalty coefficient | \(\beta _{\text{completeness}} = 10^{-12}\) |
energy consumption penalty coefficient | \(\beta _{\text{control}} = 10^{2}\) |
target point | \(z_{\text{target}} = {0.125}\) mm |
target maximal temperature at the target point | \(\theta _{\text{target}} = {1048}\) K |
p-norm in time domain | p = 20 |
material properties | |
solidus point | 858 K |
liquidus point | 923 K |
enthalpy of fusion | \({397000}\ \mathrm{J}\ \mathrm{kg}^{-1}\) |
coefficients s(θ) and κ(θ) |