Optimization of multi-layer heat shield of solar probe

The paper presents a methodology for optimal design of multilayer thermal protection coating, ensuring required operational temperature on the boundaries of layers and minimum of total mass of system. The optimization problem is solved using a computational scheme, which combines the projected Lagrangian method with the quadratic subproblem and the penalty function method. The penalty function method is characterized by a large region of convergence and provides a good initial estimate of the optimal parameters’ values for the projected Lagrangian method with excellent local convergence properties. To illustrate the implementation of the developed algorithm and the corresponding software, the paper considers the problem of choosing of the optimal layer thicknesses for the multilayer heat shield of a solar probe, exposed to extreme heat loads during operation. The main properties of the potential high-temperature materials for solar probe shield are discussed, and the results of thickness calculation for the two-layer heat shield are presented, taking into account the dependence of the thermal properties of the layers’ materials on the temperature and radiation from the heated surface of the shield.