DISCUSSION ON PAPERS 1, 2 and 3

PAPER 1

CONTRIBUTIONS

Dr L.R. Shepherd (Dragon Project)

One should not make too much out of the fact that a lot of power has to he used in recompression in the gas turbine cycle, since the compression ratio is small and sizes of rotating machinery still highly favourable compared with steam cycles. Regarding heat exchangers, those in the GT cycle may involve much higher surface areas than those in the steam cycle but they are much simpler. The recuperator in a direct cycle is in a helium environment at less than 600 C maximum temperature - there are no corrosion problems and it may leak with no severe consequences. The precooler and intercooler involve helium at relatively low temperatures with low pressures on the water side - again no major problems need arise.