Browsing NTNU Open by Author "Banasiak, Krzysztof"
Now showing items 1-20 of 68
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A modified homogeneous relaxation model for CO2 two-phase flow in vapour ejector
Haida, Michal; Palacz, Michal; Smolka, Jacek; Nowak, Andrzej J.; Hafner, Armin; Banasiak, Krzysztof (Journal article; Peer reviewed, 2016)In this study, the homogenous relaxation model (HRM) for CO2 flow in a two-phase ejector was modified in order to increase the accuracy of the numerical simulations The two- phase flow model was implemented on the effective ... -
A novel PCM accumulator for refrigerated display cabinet : design and CFD simulations
Sevault, Alexis; Banasiak, Krzysztof; Bakken, Jørn; Hafner, Armin (Chapter, 2018) -
A review on recent technological advancements in multi-ejector concept
Gullo, Paride; Hafner, Armin; Banasiak, Krzysztof; Minetto, Silvia (Chapter, 2018)As a consequence of the coming into force of the EU F-Gas Regulation 517/2014, enormous technological developments have been experienced on the part of transcritical R744 supermarket refrigeration systems. These have led ... -
Analysis of R744 refrigeration system with liquid ejectors
Singh, Simarpreet; Reddy, Amshith; Parkash, Maiya M.; Banasiak, Krzysztof; Hafner, Armin; Nekså, Petter (Chapter, 2018)In recent years, there is a rapid increase in the cooling demand. Hence, not only the consumption of energy, but also the quantity of the refrigerants released into the air is increasing globally leading to planetary ... -
Attaining a higher flexibility degree in CO2 compressor racks
Álvarez Pardiñas, Ángel; Contiero, Luca; Hafner, Armin; Banasiak, Krzysztof; Larsen, Lars F.S. (Chapter, 2020)CO2 compressor racks have shown their suitability for commercial and industrial refrigeration systems at any location and climate. Even if some references state that CO2 units can compete in capital cost with any other ... -
CFD modelling of R410A flow through an expansion valve using equilibrium and modified relaxation models
Loska, Michal; Smołka, Jacek; Haida, Michal; Kriezi, Ekaterini E.; Banasiak, Krzysztof (Peer reviewed; Journal article, 2021)The two-phase flow of R410A refrigerant through an electronic expansion valve (EEV) is modelled using two models, the Homogeneous Equilibrium Model (HEM) and Homogeneous Relaxation Model (HRM) in a CFD numerical analysis. ... -
CFD-based design algorithm for CO2 ejectors
Ringstad, Knut Emil; Banasiak, Krzysztof; Hafner, Armin (Chapter, 2021)In this work, a novel CFD-database generation algorithm for CO2 ejectors are presented. The algorithm is explained and its details discussed. A case for CFD database generation is then performed based on an ejector design ... -
Cold storage using phase change material in refrigerated display cabinets: experimental investigation
Jokiel, Michael; Sevault, Alexis; Banasiak, Krzysztof; Næss, Erling (Chapter, 2021)Refrigerated display cabinets are the main energy consumers in supermarkets. Cold thermal energy storage (CTES) using phase change materials (PCM) can significantly reduce temperature variations in a display cabinet during ... -
Comparative study of various supermarket refrigerating systems in European climate context
Gullo, Paride; Purohit, Nilesh; Dasgupta, Mani Sankar; Hafner, Armin; Banasiak, Krzysztof (Chapter, 2018)Due to the enormous carbon footprint of food retail stores the interest in natural working fluids, such as propane (R290) and CO2 (R744), has recently intensified in the commercial refrigeration sector. In this theoretical ... -
Crossing CO2 equator with the aid of multi-ejector concept: A comprehensive energy and environmental comparative study
Gullo, Paride; Tsamos, Konstantinos; Hafner, Armin; Banasiak, Krzysztof; Ge, Yunting; Tassou, Savvas A. (Journal article; Peer reviewed, 2018)The ever-stricter regulations put into effect worldwide to significantly decrease the considerable carbon footprint of commercial refrigeration sector have forced the transition to eco-friendlier working fluids (e.g. CO2, ... -
Design and simulations of Refrigerated Sea Water Chillers with CO2 ejector pumps for marine applications in hot climates
Bodys, Jakub (Master thesis, 2017)According to provided literature review, many investigations concerned improvement possibilities of carbon-dioxide refrigeration units. Basis for further development of this technology are located in environmentally friendly ... -
Design and simulations of refrigerated sea water chillers with CO2 ejector pumps for marine applications in hot climates
Bodys, Jakub; Hafner, Armin; Banasiak, Krzysztof; Smolka, Jacek; Ladam, Yves (Journal article; Peer reviewed, 2018)Various system configurations have been developed to improve the R744 systems under hot ambient conditions. However, stationary land applications are characterised by negligible limits on space for system equipment, unlike ... -
Design and simulations of refrigerated sea water chillers with CO2 ejector pumps for marine applications in hot climates
Bodys, Jakub; Hafner, Armin; Banasiak, Krzysztof; Smolka, Jacek; Ladam, Yves (Journal article; Peer reviewed, 2018)Various system configurations have been developed to improve the R744 systems under hot ambient conditions. However, stationary land applications are characterised by negligible limits on space for system equipment, unlike ... -
A detailed review on CO2 two-phase ejector flow modeling
Ringstad, Knut Emil; Allouche, Yosr; Gullo, Paride; Ervik, Åsmund; Banasiak, Krzysztof; Hafner, Armin (Peer reviewed; Journal article, 2020)Ejector-equipped vapor-compression systems for refrigeration and cooling, relying solely on (R744) as a natural working fluid, are perceived to be an eco-friendly and highly efficient solution for many applications. However, ... -
A detailed review on CO2 two-phase ejector flow modeling
Ringstad, Knut Emil; Allouche, Yosr; Gullo, Paride; Ervik, Åsmund; Banasiak, Krzysztof; Hafner, Armin (Peer reviewed; Journal article, 2020)Ejector-equipped vapor-compression systems for refrigeration and cooling, relying solely on (R744) as a natural working fluid, are perceived to be an eco-friendly and highly efficient solution for many applications. However, ... -
Dynamic modelling and validation of an air‐to‐water reversible R744 heat pump for high energy demand buildings
Artuso, Paolo; Tosato, Giacomo; Rossetti, Antonio; Marinetti, Sergio; Hafner, Armin; Banasiak, Krzysztof; Minetto, Silvia (Peer reviewed; Journal article, 2021)This paper presents a reversible heat pump based on CO2 as the refrigerant, able to provide heating, cooling, and domestic hot water to high energy demand buildings. The unit was developed and tested under the EU H2020 ... -
Efficient R744 technology for supermarket heating, cooling and refrigeration - a theoretical assessment of energy advantages in various Spanish cities
Gullo, Paride; Hafner, Armin; Banasiak, Krzysztof (Chapter, 2018)Various appealing expedients aimed at enhancing the energy efficiency of transcritical CO2 (R744) supermarket refrigerating systems have been recently developed. The concurrent adoption of these could lead such hydrofluorocarbon ... -
Ejector for the world: simplified ejector-supported CO2 refrigeration systems for all climates
Pardiñas, Ángel Á.; Fabris, F; Contiero, Luca; Selvnes, Håkon; Banasiak, Krzysztof; Hafner, Armin (Chapter, 2022)The novel configuration presented in this work simplifies the layout of ejector-supported booster systems while maintaining all the benefits of an ejector implementation. The basic version of the solution is based on: i) ... -
Energy efficient multiejector CO2 cooling system for high ambient temperature
Singh, Simarpreet; Maiya, Prakash; Hafner, Armin; Banasiak, Krzysztof; Nekså, Petter (Peer reviewed; Journal article, 2020)Experimental evaluation of a multiejector CO2 cooling system of 33 kW cooling capacity is conducted for an Indian supermarket at high ambient temperature context. The test-rig is designed to depict the actual supermarket ... -
Experimental analysis of an advanced R744 multi-ejector
Selnes, Merethe Leksen (Master thesis, 2020)Den økende interessen for energieffektive løsninger, samt å arbeide mot en mer bærekraftig framtid, viser til viktigheten av å spare energi. Dagens butikkjøleanlegg med karbondioksid har et stort potensial for å redusere ...