Listar EMC_Articles por autoría "a457b1fd-fc86-4e12-a7d2-396cd155d11d"
Mostrando ítems 1-20 de 25
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A dynamic model of a shell-and-tube condenser operating in a vapour compression refrigeration plant
Llopis, Rodrigo; Cabello López, Ramón; Torrella Alcaraz, Enrique Elsevier (2008)This work presents a mathematical model of a shell-and-tube condenser based on mass continuity, energy conservation and heat transfer physical fundamentals, whose methodology can be easily adapted for modelling any type ... -
A simplified model for shell-and-tubes heat exchangers: Practical application
Vera García, Francisco José; García Cascales, J.R.; Gonzálvez Maciá, J.; Cabello López, Ramón; Llopis, Rodrigo; Sánchez García-Vacas, Daniel; Torrella Alcaraz, Enrique Elsevier (2010)In this paper, a simplified model for the study of shell-and-tubes heat exchangers (HXs) is proposed. The model aims to agree with the HXs when they are working as condensers or evaporators. Despite its simplicity, the ... -
Comparative evaluation of the intermediate systems employed in two-stage refrigeration cycles driven by compound compressors
Cabello López, Ramón; Torrella Alcaraz, Enrique; Llopis, Rodrigo; Sánchez García-Vacas, Daniel Elsevier (2010)This work presents an experimental evaluation, from an energy analysis point of view, for two of the most used inter-stage systems in two-stage vapour compression cycles driven by compound compressors: the direct liquid ... -
Development and validation of a finite element model for water – CO2 coaxial gas-coolers
Sánchez García-Vacas, Daniel; Cabello López, Ramón; Llopis, Rodrigo; Torrella Alcaraz, Enrique Elsevier (2012-05)The gas-cooler heat exchanger is a characteristic device of the refrigeration plants that use CO2 as the working fluid in transcritical conditions. The proper gas-cooler sizing, allows getting the maximum effectiveness in ... -
Energetic evaluation of a CO2 refrigeration plant working in supercritical and subcritical conditions
Sánchez García-Vacas, Daniel; Patiño Pérez, Jorge; Sanz Kock, Carlos; Llopis, Rodrigo; Cabello López, Ramón; Torrella Alcaraz, Enrique Elsevier (2014-05)Unlike other refrigerants, R744 (or carbon dioxide) has a very low critical temperature (30.98 °C) which hampers working in subcritical conditions especially when the environment is used as a heat rejection sink. Accordingly, ... -
Energetic evaluation of an internal heat exchanger in a CO2 transcritical refrigeration plant using experimental data
Torrella Alcaraz, Enrique; Sánchez García-Vacas, Daniel; Llopis, Rodrigo; Cabello López, Ramón Elsevier (2011)The performance of an Internal Heat Exchanger (IHX) operating in a CO2 transcritical refrigeration plant is analysed, from an energetic point of view, in this work. The evaluation is based on experimental data by contrasting ... -
Energy and environmental comparison of two-stage solutions for commercial refrigeration at low temperature: Fluids and systems
Llopis, Rodrigo; Sánchez García-Vacas, Daniel; Sanz Kock, Carlos; Cabello López, Ramón; Torrella Alcaraz, Enrique Elsevier (2015-01-15)International agreements will restrict in the near future the use of high-GWP refrigerants in Europe. These restrictions will favour the implantation of refrigeration systems with low-GWP fluids, especially in applications ... -
Energy evaluation of R152a as drop in replacement for R134a in cascade refrigeration plants
Cabello López, Ramón; Sánchez García-Vacas, Daniel; Llopis, Rodrigo; Catalán-Gil, Jesús; Nebot-Andres, Laura; Torrella Alcaraz, Enrique Elsevier (2017-01)An experimental comparison has been performed of a cascade refrigeration facility working with the refrigerant pairs R134a/R744 and R152a/R744. This kind of facility is suitable for industrial and commercial refrigeration ... -
Energy influence of the IHX with R22 drop-in and long-term substitutes in refrigeration plants
Cabello López, Ramón; Torrella Alcaraz, Enrique; Llopis, Rodrigo; Sánchez García-Vacas, Daniel; Larumbe, J. A. Elsevier (2013-01-10)This work focuses on the investigation of new drop-in or long-term refrigerants for low evaporating temperatures that can be used as substitutes for HCFC-22, which is gradually being phased-out. This process is already in ... -
Energy perfomance evaluation of R1234YF, R1234ze (E), R6600a, R290 and R152a as low-GWP R134a alternatives
Sánchez García-Vacas, Daniel; Cabello López, Ramón; Llopis, Rodrigo; Arauzo Pérez, Ivan; Catalán-Gil, Jesús; Torrella Alcaraz, Enrique Elsevier (2017-02)In 2014, the Directive 517/2014 was introduced by European Parliament to reduce the use of high-GWP greenhouse gases in the European area in order to limit global climate change in accordance with the objectives marked by ... -
Experimental analyis of energy performance of modified single-stage CO2 transcritical vapour compression cycles based on vapour injection in the suction line
Sánchez García-Vacas, Daniel; Cabello López, Ramón; Patiño Pérez, Jorge; Llopis, Rodrigo; Torrella Alcaraz, Enrique Elsevier (2012-12)This work presents the experimental evaluation of the energy performance of a modified single-stage CO2 transcritical refrigeration plant with an internal heat exchanger (IHX) based on vapour injection in suction line. ... -
Experimental evaluation of a R134a/CO2 cascade refrigeration plant
Sanz Kock, Carlos; Llopis, Rodrigo; Sánchez García-Vacas, Daniel; Cabello López, Ramón; Torrella Alcaraz, Enrique Elsevier (2014)We present the experimental evaluation of a R134a/CO2 cascade refrigeration plant designed for low evaporation temperature in commercial refrigeration applications. The test bench incorporates two single- stage vapour ... -
Experimental evaluation of an Internal Heat Exchanger in a CO2 subcritical refrigeration cycle with gas-cooler
Llopis, Rodrigo; Sanz Kock, Carlos; Cabello López, Ramón; Sánchez García-Vacas, Daniel; Torrella Alcaraz, Enrique Elsevier (2015-04-05)We present the experimental evaluation of an internal heat exchanger or suction-line/liquid-line heat exchanger in a CO2 subcritical refrigeration plant with gas-cooler. The plant, driven by a 1.5kW CO2 semi hermetic ... -
Experimental evaluation of HCFC-22 replacement by the drop-in fluids HFC-422A and HFC-417B for low temperature refrigeration applications
Llopis, Rodrigo; Cabello López, Ramón; Sánchez García-Vacas, Daniel; Torrella Alcaraz, Enrique; Patiño Pérez, Jorge; Sánchez, J. G. Elsevier (2011-05)The Regulation CE-1005/2009 has banned the use of virgin HCFC-22 in Europe from the 31st December 2009, because it contains chlorine, although its use is allowed up to the 31st December 2014 if it is recycled. Now, ... -
Experimental evaluation of the energy efficiency of a CO2 refrigerating plant working in transcritical conditions
Cabello López, Ramón; Sánchez García-Vacas, Daniel; Llopis, Rodrigo; Torrella Alcaraz, Enrique (2008)This work presents the experimental evaluation of the energy efficiency and optimal gas-cooler pressures of a single-stage refrigerating plant working with carbon dioxide as refrigerant in transcritical conditions. The ... -
Experimental Evaluation of the Energy Performance of an Air Vortex Tube when the Inlet Parameters are Varied
Torrella Alcaraz, Enrique; Patiño Pérez, Jorge; Sánchez García-Vacas, Daniel; Llopis, Rodrigo; Cabello López, Ramón Bentham Open (2013)he paper presents the analysis of the energy performance of an air vortex cooling tube under variations of the air inlet properties, with t hree independent experimental tests validated through the energy balance ... -
Experimental evaluation of the inter-stage conditions of a two-stage refrigeration cycle using a compound compressor
Torrella Alcaraz, Enrique; Llopis, Rodrigo; Cabello López, Ramón Elsevier (2009)The aim of the present paper is to detail an analysis, based on experimental data, of the inter-stage working conditions of a two-stage vapour compression facility equipped with a compound compressor, which operates with ... -
HCFC-22 replacement with drop-in and retrofit HFC refrigernants ina a two-stage refrigeration plant for low temperature
Sánchez García-Vacas, Daniel; Cabello López, Ramón; Llopis, Rodrigo; Torrella Alcaraz, Enrique Elsevier (2012)The world community has committed to eliminate the HCFC-22 refrigerant to a series of deadlines according to the agreements taken during the 19th Montreal Protocol meeting in September 2007. This phase-out, which is already ... -
Influence of the superheat associated to a semihermetic compressor of a transcritical CO<sub>2</sub> refrigeration plant
Sánchez García-Vacas, Daniel; Torrella Alcaraz, Enrique; Cabello López, Ramón; Llopis, Rodrigo Elsevier (2010)This work evaluates, from an energetic point of view, the effects of the superheat caused in the refrigerant by the electric motor cooling (SH<sub>SC</sub>) in a semihermetic compressor installed in an experimental ... -
Las máquinas de producción de frío por adsorción con la mezcla sílica gel-agua
Torrella Alcaraz, Enrique; Sánchez García-Vacas, Daniel; Cabello López, Ramón; Patiño Pérez, Jorge; Llopis, Rodrigo Reed Business Information (2011)El objetivo del trabajo es presentar una revisión de las máquinas frigoríficas tritérmicas le adsorción,con mencIón especial en las que trabajan con la mezcla silicagel (o gel de sílice) – agua. La estructura seguida se ...