Optimal operation of simple cooling cycles
نویسندگان
چکیده
In this paper we consider the selection of controlled variables for two vapour compression cycles. One is a conventional sub-critical ammonia cooling cycle and the other is a trans-critical CO2 cooling cycle. The two cycles have quite different operational properties. For the ammonia cycle we find that several simple control structures gives acceptable performance in terms of achieving in practice the optimal thermodynamic efficiency. For the CO2 cycle on the other hand, a combination of measurements is necessary to achieve self-optimizing control.
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