Fig. 2. Generation of high pressure by direct (top) and indirect (bottom)
compression of the pressure-transmitting medium (37)
Indirect compression
This technique uses a high-pressure intensifier to pump a
pressure medium from a reservoir into a closed high-pressure
vessel until the desired pressure is reached (Fig. 2).
Heating of the pressure medium
It utilizes expansion of the pressure fluid with increasing
temperature to generate high pressure. This method is therefore
used when high pressure is applied in combination with high
temperature and requires very accurate temperature control
within the entire internal volume of the pressure vessel (5).