Gas turbines often use regenerative cycles to improve overall operating efficiency. The schematic shown in Figure P3-18 is an example of a gas turbine engine with a regenerator. Extensive cycle analyzes have established that for optimum cycle operating efficiency, the following specifications are required fot the regenerator. Using heat transfer surfaces available in the book, design that regenerator. Examine different surfaces and support your choice of surfaces and your design. This is an airborne device, so size and weight are important. Use properties of air for both fluids. How important is the pressure-drop constraint on the overall size (volume) of the heat exchanger?