超导MRI主磁体优化设计的模拟退火算法

Simulated annealing approach for the optimization design of superconducting MRI main magnet

在进行MRI(magneticresonanceimaging)超导主磁体的设计时常采用优化设计的方法,将各设计参数看作连续变量处理,但实际上很多参数是离散变量,为了更符合工程实际,将超导MRI主磁体的设计作为一个含有离散变量的全局优化问题。建立了适用于多种超导MRI主磁体结构的数学模型,包括设计变量、目标函数、约束条件等,选用了适用于MRI超导主磁体优化设计的含有离散变量的模拟退火算法进行设计。算例结果表明,本文选取的数学模型和优化算法是有效的,能够达到超导MRI主磁体设计的要求。

Optimization design is often used in the design of MRI superconducting main magnet, where all variables are treated as continuous ones. According to the fact that not all variables are continuous, here the design problem is seen as a global optimization problem with discrete variables. A mathematical model is built including the definition of variables, objective function and constraints. A simulated annealing algorithm suitable for the optimization of mixed integer non-linear programming problems is used to design MRI SC main magnet. An example is given to illustrate the effectiveness of the mathematical model and the optimization algorithm.