Abstract
This paper deals with recuperative plate-type heat-exchanger elements for a composite air preheater for automotive gas turbines. The general requirements and optimization of the essential dimensions of such an element are discussed.
Such optimization leads to the smallest possible weight for a given temperature and pressure efficiency. As these two efficiencies affect the specific fuel consumption of the gas turbine, two further optimizations lead to: (a) The best pressure ratio of the turbomachines for given initial temperatures; and (b) the best temperature and pressure efficiency of the air preheater. The weight of this heat exchanger affects the performance of the vehicle propelled by the gas-turbine unit in different ways. Further optimization therefore leads to the best weight of the air preheater at a given average speed.
Cost considerations which affect the design of the element are influenced by the method of manufacture and the choice of materials as well as the method of maintaining clean channels in the heat-exchanger elements.