Abstract: The energy balance, air internal energy,
enthalpy and exergy transfers of high pressure switching expansion
reduction (SER) are comparatively analyzed in this paper to give a
better understanding about the exergy analysis and its difference
between energy conversion analyses for the pneumatics. In SER, the
exergy transfer efficiency is much lower than the enthalpy
efficiency. The enthalpy efficiency is primarily related to the
initial pressure of supply tanks, and the exergy efficiency is
primarily related to the pressure reduction ratios. Heat transfers
increase the internal energy, enthalpy and exergy of air; the
influence on exergy is relatively small. The total enthalpy in SER
decreases as the air temperature decreases in the expansion process
of the air. And exergy loss is primarily related to the irreversible
process of isenthalpic throttling but not energy conversion. Based
on the analyses, to improve the exergy efficiency of the pneumatics,
the pressure reduction without power output should be avoided.
LUO Yu-xi (罗语溪), WANG Xuan-yin (王宣银), LEI Jun-bo (雷军波)
. Enthalpy and Exergy Transfers of High Pressure Switching Expansion Reduction[J]. Journal of Shanghai Jiaotong University(Science), 2012
, 17(1)
: 45
-052
.
DOI: 10.1007/s12204-012-1228-6
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