R.Z. Wang’s research while affiliated with Shanghai Jiao Tong University and other places

... In the actual cycle, there are various heat transfer and friction losses. For simplification, the following assumptions are made for the CHP cycle: 1) The pressure change only occurs at the compressor and the throttle valve; 2) The heat dissipation loss of the working fluid in the evaporator condenser, evaporator, and condenser is ignored; 3) The throttling process is adiabatic throttling [5] ; 4) The superheat and subcooling of the equipment are both 3˚C. ...

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Cycle performance study on cascade high temperature air source heat pump system

... Additionally, adsorption technology is straightforward to develop and implement, enabling the removal of various pollutants from water systems. Nonetheless, the challenges of limited selectivity and the generation of hazardous waste due to the difficulty in separating the adsorbent from the pollutants are notable drawbacks of this technique [29][30][31][32][33]. Nanomaterials have recently attracted significant attention in wastewater treatment due to their exceptional properties, such as high adsorption capacity, small particle size, large surface area, high catalytic activity, and thermal stability. ...

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An investigation of the adsorption of Congo red dye on two naturally occurring adsorbents Hydroxyapatite and Bentonite: An Experimental Analysis, DFT calculations, and Monte Carlo simulation

... Shao et al. developed a highly efficient DCHE-based HP and applied it to the real-world AC unit in the rail sector, achieving an $40% improvement in COP and contributing to the decarbonization of rail transportation. 22 Although HPSSs have come a long way over the past decade, there are still some challenges that needed to be addressed. First, the desorption process of sorbent requires a high temperature to create the necessary chemical potential difference between the captured water and the water vapor in the surrounding air, driving the water release process of the sorbent. ...

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Heat-pump-coupled sorbent system toward efficient atmospheric water production and indoor air conditioning

... 28 It was used experimentally to determine the heat transfer and diffusion coefficients that then serve as inputs into a full-scale adsorption chiller model. 28 50 The different desiccants investigated were silica gel, FAM-Z01, FAM-Z02, FAM-Z05, HKUST-1 and MIL-101(Cr). 50 The MIL-101(Cr)-coated heat exchanger had the highest CPUE (above 0.95), followed by FAM-Z02 and HKUST-1 in joint second, FAM-Z01 and FAM-Z05 in joint third and lastly the silica gel-coated heat exchanger (CPUE 0.6-0.8). ...

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Enhanced moisture sorption through regulated MIL-101(Cr) synthesis and its integration onto heat exchangers

... This work aimed to reach a coefficient of performance (COP) of greater than 4 in every operating point and to find the boundary conditions to achieve this goal. In their study, Jiang et al. [5] used the same refrigerant and supply temperatures up to 100 • C. They reached a COP of 3.67 at a temperature lift of 50 K and developed a semi-empiric simulation model. ...

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Maximising the potential of deep geothermal energy: Thermal output increase by large-scale heat pumps

... These systems are commonly referred to as Hybrid Compressor Absorption Heat Transformers (HCAHT), although the naming of the two options is not unique in the literature. The first system is also called Hybrid Absorption Compressor Heat Pump (HCAHP) (Gao et al., 2021a;Zhang et al. 2022), while the second is called Absorption Compression Heat Transformer (ACHT) (Zhou et al., 2024), Compression Assisted Heat Transformers (CAHT) (Gao et al., 2021a) or simply Compression Heat Transformer (CHT), as will be done in this paper. In either case, the resulting system combines the features of a heat transformer and a heat pump, exploiting the ability of the former to upgrade low temperature heat with the flexibility and additional lift capability provided by the mechanical compressor of the latter. ...

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Compressor-assisted heat transformer for low-grade heat recovery

... Current research on temperature rise in screw machinery primarily focuses on heat pumps. [4][5][6] Tamura et al. 7 demonstrated the feasibility of using screw compressors and expanders under high-temperature conditions by analyzing the thermal cycle, equipment applications, thermal fluid selection, and performance evaluation of hightemperature heat pump systems. Wu et al. 8 investigated thermal deformation and clearance variations in oil-free twin-screw compressors (TSC) under low-temperature conditions, modifying clearance values to ensure stable operation. ...

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Study of the effects of flow and temperature rise within the operation of twin-screw controlled pumps for seawater desalination

... Zühlsdorf et al. [14] proposed MVR and RB systems, conducting an economic evaluation under operating conditions capable of delivering output temperatures above 280 °C, which verified the feasibility under given conditions. Huang et al. [15] constructed a two-stage CO2 RB system incorporating injection and an internal heat exchanger, performing simulation analysis according to the design parameters and an economic evaluation at an output temperature level of approximately 150 °C. Wang et al. [16] modeled various RB systems with different placements of a turbocharger and an additional compressor, analyzing the impact of the pressure ratios on performance and examining the feasibility of supplying heat at space heating levels. ...

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Thermal Performance Design and Analysis of Reversed Brayton Cycle Heat Pumps for High-Temperature Heat Supply

... The calculated cold ESD based on crystallization experiment reached 300 kWh/m 3 . Mehari et al. [37] [38]. Except for the aforementioned studies on thermodynamic cycles and components, system-level research has already been carried out. ...

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Heat pump assisted open three-phase sorption thermal battery for efficient heat storage

... An ESD of 447 kWh/m 3 and a coefficient of performance (COP) of 0.73 were obtained with LiBr-H 2 O working pair according to simulation result. Mehari et al. [40] combined an OTSTB with an evaporative cooler. Under the ARI summer conditions and charge temperature of 80 • C, the combined system showed an ESD of 563 kWh/m 3 and a COP of 1.2. ...

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Heat pump assisted open three-phase sorption thermal battery for efficient heat storage