THERMAL-ANALYSIS OF COMPOSITE SUPERCONDUCTORS SUBJECTED TO TIME-DEPENDENT DISTURBANCES

A one-dimensional heat conduction equation with time-and temperature-d ependent heat sources was employed to study the steady-state and trans ient response of a composite superconductor subjected to a thermal dis turbance. An integral formulation was used to solve the steady-state p roblem of current redistribution and heat generation. The results of t he integral formulation are compared with those of an analytical solut ion. The two solutions agree with each other except when the analytica l solution fails as the temperature in the superconductor begins to ex ceed the critical temperature. Transient solutions were obtained by th e finite-difference technique and the results are compared with a know n analytical solution. Results of numerical calculations of the transi ent response of a composite superconductor subjected to an initial pul sed disturbance are presented. It is demonstrated that the superconduc tor can switch between the superconducting and the current-sharing sta te. The transient response and the stability of the composite conducto r depend on the magnitude and duration of the disturbance, the dimensi onless temperature theta, and the dimensionless parameter phi.