PDF Publication Title:
Text from PDF Page: 005
1 2 3 4 5 6 7 8 9 probably free from any restrictions in the future. On the other hand the challenge is on their global cost, due to the (still) high price of some components and to the possibility of showing a lower efficiency. Both heat for space heating and cooling capacity in favour of air conditioning can be provided by such a system (Cortella et al, 2018), which can be eventually coupled with a heat storage (Polzot et al, 2016b, 2016c). However most applications still involve just heat recovery, mainly for its simplicity. Furthermore, when excess heat is available, it can be successfully supplied to a district heating network. Adrianto et al (2018) estimated that giving priority to space heating and supplying the remaining quota to district heating is the most effective scenario in terms of energy and cost, when compared to other configurations and control rules with different priorities. 10 11 12 13 14 15 16 17 18 19 20 additional outdoor air-cooled evaporator, which can be used as a supplemental heat source. In this way the 21 In this paper a R744 refrigeration system is considered, to satisfy the cooling load required by chilled and frozen food storage and display equipment in a medium-sized supermarket, while supplying DHW and space heating. The system is controlled to meet the full heating demand of the building and is equipped with an refrigerating unit acts as a heat pump, with the only drawback that in humid and cold climate the external evaporator needs frequent defrost operations, the same as with air to water heat pumps. An alternative could 22 23 24 25 be the insertion of a third heat exchanger on the high stage pressure line, to provide heat while performing 26 further subcooling of the refrigerant (Sheehan et al, 2018). Dynamic simulations of the refrigeration system, 27 28 29 30 mild/warm climate conditions. The results in terms of energy consumption are compared to alternative 31 including mutual interactions with the building and with the HVAC, have been carried out at three refrigeration systems without heat recovery, such as the R744 booster system itself, the R404A direct 32 33 34 35 take care of space heating and DHW loads. 36 expansion system and the R134a/R744 cascade system. For all these schemes, heat pumps are considered to 37 38 39 40 Commercial refrigeration units are characterized by the presence of two levels of evaporating temperature: 41 2. SYSTEM DESCRIPTION the Medium Temperature (MT) level, around -8 °C, in order to supply the cooling demand from the chilled 42 43 44 45 The schematic of the investigated system (Booster with Heat Recovery – BHR) and the corresponding 46 food display cabinets and the Low Temperature (LT) one, around -35 °C, for frozen food storage equipment. thermodynamic diagram are depicted in Fig. 1. The baseline is a booster system with parallel compressor 47 48 49 50 the flash gas. The liquid is expanded to the pMT and to the pLT evaporating pressure levels, corresponding to 51 (Booster – B), characterized by a receiver, at the intermediate pressure pINT, which separates the liquid from the MT and LT evaporating temperatures respectively. In subcritical operation valve SOL1 is closed and the 52 53 54 55 compressors. In transcritical operation, when a predefined production of flash gas is reached, the valve SOL1 56 flash gas is expanded in valve EV1 to the MT pressure level to be finally compressed by the High Stage (HS) is open, the by-pass valve EV1 is closed and thus the flash gas is compressed to the high stage pressure (pHS) 57 58 59 60 exchangers are introduced in series at the exit of the high stage compressors rack. The first one (HX1) is 61 62 63 64 65 by a parallel compressor. In order to perform heat recovery at two temperature levels, separate heatPDF Image | R744 BOOSTER INTEGRATED SYSTEM
PDF Search Title:
R744 BOOSTER INTEGRATED SYSTEMOriginal File Name Searched:
rj34_sub.pdfDIY PDF Search: Google It | Yahoo | Bing
CO2 Organic Rankine Cycle Experimenter Platform The supercritical CO2 phase change system is both a heat pump and organic rankine cycle which can be used for those purposes and as a supercritical extractor for advanced subcritical and supercritical extraction technology. Uses include producing nanoparticles, precious metal CO2 extraction, lithium battery recycling, and other applications... More Info
Heat Pumps CO2 ORC Heat Pump System Platform More Info
CONTACT TEL: 608-238-6001 Email: greg@infinityturbine.com (Standard Web Page)