Optimization Model and Algorithm for the Size of Function Areas in Distribution Center under Constraint

The inside layout problem of distribution center (DC) is an important problem in the early phase of the logistics network design, but related research is little. The problem is that in order to minimize the total cost under the condition of the total available space in a DC is restrictive; the design in the DC is required to determine rationally the product allocation to the functional areas as well as the size of each functional area. Based on the function of the areas, the freight flows in the DC were described as eight basic flows. A higher level model that jointly determines the functional area sizes and the product allocation in a way that minimizes the total freight handling cost was presented and the simulated annealing algorithm was used to solve and analyze it. The optimization of the allocation of the product was carried out in the outer sub-algorithm, and based on the allocation; the sizes of the main functional areas were optimized in the inner sub-algorithm. Application denoted the optimization method operated rapidly and the result was rational, and compared with the initial solutions, the object cost of the optimal solutions relatively save cost 9.48% ∼ 47.29%, so it provides scientific guidance for the design in the DC.