A Pirect Energy Recovery System Using Periodic Focusing without Grids

Results from a computational study of the efficiency of a direct energy recovery system are presented. This system is similar to R. F. Post´s original (gridless) periodic-focus system. However, the computer code used here allows more flexibility than that used by Post. His code requires analytic expressions for the potentials; this code requires only the values of potential on the boundaries. Consequently, the code can be applied to systems where analytic expressions have not been written for the potential. The incident beam used in this study had an average thickness of 0.42 m (as might be expected in an ideal reactor situation) and a maximum divergence angle of ±3.3°. Each of the systems tested, when operating at optimum efficiency, recovered 80% of the energy, as compared to 91% for Post´s gridded periodic system.