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Support
-T1 |
compressor |
-T2 |
ejector |
-E1 |
evaporator |
-E2 |
gas cooler |
-E3 |
internal heat exchanger |
-VZ |
filter drier |
-PG |
indicator sight glass |
-C |
receiver / separator |
steps. The first stage of expansion of the supercritical gas takes place in the high-pressure valve. The supercritical gas liquifies and gives off heat to the flash gas. The liquid collects in the receiver. The pressurised receiver has intermediate
Single stage system with parallel compression.
This system is similar to the gas bypass system. This system is applied also in supermarkets and other applications with continuous cooling capacity.
Two stage booster system: In the CO2 two-stage systems both the compression and the expansion works in two
pressure. The second stage of expansion takes place in the thermostatic expansion valve. The evaporated refrigerant is compressed in the LP stage to MP. The discharge flow of the LP compressor is mixed with the suction flow of the intermediate pressure evaporators. The total mass flow is compressed in the high-pressure stage to the supercritical pressure of the gas cooler( HP).
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RACA Journal I October 2025 www. refrigerationandaircon. co. za