The Stratification Coefficient Approach for Predicting the Performance of Solar Air Heating Systems Utilizing Packed Bed Heat Storage

The stratification coefficient approach is refined to allow its use for predicting the performance of solar air heating systems utilizing packed bed thermal energy storage. The partial differential equation governing the storage is eliminated from the analysis in the stratification coefficient approach. Elimination of this differential equation greatly simplifies the computation of system performance. Performance predictions calculated by the stratification coefficient approach are compared to those calculated by a numerical solution to the storage differential equation. The comparisons show good agreement between the two methods. Computation time is reduced by an order of magnitude through the use of the stratification coefficient approach. Extension of the stratification coefficient approach to solar water heating systems is discussed.