Gray modeling of heat-pump-surrounding system exergy efficiency

The paper assumes the heat-pump-surrounding (HPS) system as a gray system and makes a gray model, GM (1, N), for the HPS system to assess the system exergy efficiency. It attains the system exergy efficiency laws of the HPS system through some steps including the gray relationship analysis, creating gray number, setting up GM (1, N) model, and so on and also verifies the accuracy of the laws from the gray model. It shows that gray system theory can be used in the HPS system to make gray models and present accuracy system exergy efficiency laws when the HPS as a whole system lacks enough practically tested data. And it also suggests the variables linked lower-level heat source parameters should be given obviously in the relation analyzing the HPS system exergy efficiency.