Abstract
We propose a shape optimization method over a fixed grid. Nodes at the intersection with the fixed grid lines track the domain’s boundary. These “floating” boundary nodes are the only ones that can move/appear/disappear in the optimization process. The element-free Galerkin (EFG) method, used for the analysis problem, provides a simple way to create these nodes. The fixed grid (FG) defines integration cells for EFG method. We project the physical domain onto the FG and numerical integration is performed over partially cut cells. The integration procedure converges quadratically. The performance of the method is shown with examples from shape optimization of thermal systems involving large shape changes between iterations. The method is applicable, without change, to shape optimization problems in elasticity, etc. and appears to eliminate non-differentiability of the objective noticed in finite element method (FEM)-based fictitious domain shape optimization methods. We give arguments to support this statement. A mathematical proof is needed.
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References
Belytschko T, Lu YY, Gu L (1994) Element-free Galerkin methods. Int J Numer Methods Eng 37:229–256
Belytschko T, Krongauz Y, Organ D, Fleming M, Krysl P (1996) Meshless methods: an overview and recent developments. Comput Methods Appl Mech Eng 139:3–47
Bobaru F (2001) Meshless methods in shape optimization of linear elastic and thermoelastic solids. Ph.D. dissertation, Cornell University, Ithaca, NY
Bobaru F, Mukherjee S (2001) Shape sensitivity analysis and shape optimization in planar elasticity using the element-free Galerkin method. Comput Methods Appl Mech Eng 190(32–33):4319–4337
Bobaru F, Mukherjee S (2002) Meshless approach to shape optimization of linear thermoelastic solids. Int J Numer Methods Eng 53(4):765–796
Bobaru F, Rachakonda S (2004a) Boundary layer in shape optimization of convective fins using a meshfree approach. Int J Numer Methods Eng 60(7):1215–1236
Bobaru F, Rachakonda S (2004b) Optimal shape profiles for cooling fins of high and low conductivity. Int J Heat Mass Transfer 47(23):4953–4966
Chen JS, Wang HP (2000) New boundary condition treatments in meshless computation of contact problems. Comput Methods Appl Mech Eng 187:441–468
Duarte CAM (1996) The HP cloud method. Ph.D. dissertation, University of Texas at Austin, Austin, Texas, USA
Farlow JO, Thompson CV, Rosner DE (1976) Plates of stegosaurus. Forced convection heat loss fins? Science 192:1123–1125
Garcia-Ruiz MJ, Steven GP (1999) Fixed grid finite elements in elasticity problems. Eng Comput 16(2–3):145–164
Grindeanu I, Choi KK, Chen JS, Chang KH (1999) Shape design optimization of hyperelastic structures using a meshless method. AIAA J 37(8):990–997
Haslinger J, Mäkinen RAE (2003) Introduction to shape optimization. SIAM, Philadelphia
Haslinger J, Maitre JF, Tomas L (2001a) Fictitious domains methods with distributed Lagrange multipliers Part I: application to the solution of elliptic state problems. Math Models Methods Appl Sci 11(3):521–547
Haslinger J, Maitre JF, Tomas L (2001b) Fictitious domains methods with distributed Lagrange multipliers Part II: application to the solution of shape optimization problems. Math Models Methods Appl Sci 11(3):549–563
Kim NH, Choi KK, Botkin ME (2002) Numerical method for shape optimization using meshfree method. Struct Multidisc Optim 24(6):418–429
Mäkinen RAE, Rossi T, Toivanen J (2000) A moving mesh fictitious domain approach for shape optimization problems. Mathematical Modelling and Numerical Analysis 34(1):31–45
Nayroles B, Touzot G, Villon P (1992) Generalizing the finite element method: diffuse approximation and diffuse elements. Comput Mech 10:307–318
Norato J, Haber R, Tortorelli D, Bendsoe MP (2004) A geometry projection method for shape optimization. Int J Numer Methods Eng 60(14):2289–2312
Rabczuk T, Belytschko T (2005) Adaptivity for structured meshfree particle methods in 2D and 3D. Int J Numer Methods Eng 63(11):1559–1582
Rachakonda S (2003) Optimal shape design of thermal systems with meshfree methods over a fixed grid. Master thesis, University of Nebraska-Lincoln, Lincoln, Nebraska, USA
Turk G, O’Brien JF (2002) Modelling with implicit surfaces that interpolate. ACM Trans Graph 21(4):855–873
White FM (1988) Heat and mass transfer. Addison-Wesley
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Bobaru, F., Rachakonda, S. E(FG)2: a new fixed-grid shape optimization method based on the element-free galerkin mesh-free analysis. Struct Multidisc Optim 32, 215–228 (2006). https://doi.org/10.1007/s00158-006-0018-x
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DOI: https://doi.org/10.1007/s00158-006-0018-x