英语翻译
In most cases,the volume flowrate through the
steam expander is no greater than that through the
turbine.It should be noted that in the case of the watercooled
system,not only is the Hexane turbine very
large,but the condensing temperature is only 0.3 bar,
which means that the ORC system would have to be
completely hermetically sealed in order to prevent
problems with maintaining a vacuum in the condenser.
This is normally achieved by the turbine being
directly linked to a high-speed generator with an invertor
control to produce output at 50/60 Hz.Such units
are expensive.Incontrast,the screwexpander could be
coupled directly to a two-pole generator or through a
low-cost belt drive and its cost would be only a fraction
of that of the equivalent turbine.