Jose R Garcia-Cascales | Universidad Politecnica de Cartagena (original) (raw)
Professor at Technical University of Cartagena, Spain, Industrial Engineer and PhD in Thermal Engineering and Thermal Properties of Matter at Technical University of Valencia, Spain. My areas of interest are Refrigeration, Heat Pumps, and Heat Transfer and Thermohydraulics in general.
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Papers by Jose R Garcia-Cascales
A M aÁ ngeles y Pepe d : total derivative. dt : differential of time. dA : differential of surfac... more A M aÁ ngeles y Pepe d : total derivative. dt : differential of time. dA : differential of surface. dS : differential of surface. dV : differential of volume. e : internal energy. e i : unitary vector in the direction of axis i. E : total energy (e + u 2 2). F : flux vector. g : gravity. h : enthalpy. h i : interfacial heat transfer coefficients. h w : wall heat transfer coefficients. H : total enthalpy (h + u 2 2). J: general outward flux. J : jacobian matrix. m k : mass transfer from phase k to the other phase. n k : outwards normal vector to the surface of phase k. n : normal vector to a surface. p : pressure. q : surface heat flux. q :volume heat source. q i : interfacial heat transfer. S : source term vector. r : position vector. s : entropy. S c : surface of the control volume. S I : surface of the interface. t : time. t : stress in a determined direction. T : stress tensor. u : velocity of a point. u c : velocity of the surface of the control volume S c. U : velocity of a particle. V : vector of primitive variables. V c : control volume. W : vector of conserved variables. z : axis coordinate.
Science and Technology for the Built Environment, 2015
ABSTRACT
Science and Technology for the Built Environment, 2015
ABSTRACT The selection of the suitable correlations for calculating the heat transfer coefficient... more ABSTRACT The selection of the suitable correlations for calculating the heat transfer coefficients and the pressure drop plays a fundamental role in the use of semi-empirical models for the simulation of the performance of a heat exchanger. Therefore, a discussion about the best way for validating a condenser model and choosing the best set of correlations for both the heat transfer coefficients and pressure drop is presented. The studies were performed for both the air and refrigerant side in a round tube and plate fin condenser. A test campaign was specially designed to cover a wide range of key parameters such as air velocity, condensation temperature, refrigerant mass flowrate and condenser subcooling. The options for defining the boundary conditions in the model and the accuracy metrics are discussed in detail, allowing the identification of the most suitable correlations. By using this set of correlations, the prediction error is within an error band of ±0.4°C for the condensation temperature and ±0.6% in terms of capacity.
International Journal of Refrigeration, 2015
The present paper reports condensing two-phase flow pressure drop gradient and heat transfer coef... more The present paper reports condensing two-phase flow pressure drop gradient and heat transfer coefficient (HTC) inside a mini-channel multiport tube with R1234yf and R134a. Several models available in the literature are used to compare predictions of these two fluids. Experimental data are analysed to get the influence of saturation temperature, mass flux, vapour quality and fluid properties. HTC values of R1234yf seem to be lower than R134a under similar conditions. Two-phase flow pressure drops are also lower in the case of the new refrigerant R1234yf.
En este artículo se estudia el modelado global de un sistema de absorción BrLi-H 2 O que satisfac... more En este artículo se estudia el modelado global de un sistema de absorción BrLi-H 2 O que satisface las necesidades de climatización de un aula de un centro formación en la localidad murciana de Puerto Lumbreras. Este sistema utiliza un conjunto de colectores solares para satisfacer las necesidades térmicas del generador de vapor de la máquina de absorción. Para la simulación dinámica del sistema se ha utilizado el programa TRNSYS. El local a climatizar se ha modelado utilizando el subprograma de TRNSYS llamado PREBID. En el trabajo se presta especial atención al modelado de la máquina de absorción mediante redes neuronales que posteriormente ha sido implementado en TRNSYS y se plantean algunas conclusiones como consecuencia del estudio realizado. PALABRAS CLAVE: Modelado de sistemas de absorción, transmisión de calor, energía solar, refrigeración solar, redes neuronales.
A M aÁ ngeles y Pepe d : total derivative. dt : differential of time. dA : differential of surfac... more A M aÁ ngeles y Pepe d : total derivative. dt : differential of time. dA : differential of surface. dS : differential of surface. dV : differential of volume. e : internal energy. e i : unitary vector in the direction of axis i. E : total energy (e + u 2 2). F : flux vector. g : gravity. h : enthalpy. h i : interfacial heat transfer coefficients. h w : wall heat transfer coefficients. H : total enthalpy (h + u 2 2). J: general outward flux. J : jacobian matrix. m k : mass transfer from phase k to the other phase. n k : outwards normal vector to the surface of phase k. n : normal vector to a surface. p : pressure. q : surface heat flux. q :volume heat source. q i : interfacial heat transfer. S : source term vector. r : position vector. s : entropy. S c : surface of the control volume. S I : surface of the interface. t : time. t : stress in a determined direction. T : stress tensor. u : velocity of a point. u c : velocity of the surface of the control volume S c. U : velocity of a particle. V : vector of primitive variables. V c : control volume. W : vector of conserved variables. z : axis coordinate.
Science and Technology for the Built Environment, 2015
ABSTRACT
Science and Technology for the Built Environment, 2015
ABSTRACT The selection of the suitable correlations for calculating the heat transfer coefficient... more ABSTRACT The selection of the suitable correlations for calculating the heat transfer coefficients and the pressure drop plays a fundamental role in the use of semi-empirical models for the simulation of the performance of a heat exchanger. Therefore, a discussion about the best way for validating a condenser model and choosing the best set of correlations for both the heat transfer coefficients and pressure drop is presented. The studies were performed for both the air and refrigerant side in a round tube and plate fin condenser. A test campaign was specially designed to cover a wide range of key parameters such as air velocity, condensation temperature, refrigerant mass flowrate and condenser subcooling. The options for defining the boundary conditions in the model and the accuracy metrics are discussed in detail, allowing the identification of the most suitable correlations. By using this set of correlations, the prediction error is within an error band of ±0.4°C for the condensation temperature and ±0.6% in terms of capacity.
International Journal of Refrigeration, 2015
The present paper reports condensing two-phase flow pressure drop gradient and heat transfer coef... more The present paper reports condensing two-phase flow pressure drop gradient and heat transfer coefficient (HTC) inside a mini-channel multiport tube with R1234yf and R134a. Several models available in the literature are used to compare predictions of these two fluids. Experimental data are analysed to get the influence of saturation temperature, mass flux, vapour quality and fluid properties. HTC values of R1234yf seem to be lower than R134a under similar conditions. Two-phase flow pressure drops are also lower in the case of the new refrigerant R1234yf.
En este artículo se estudia el modelado global de un sistema de absorción BrLi-H 2 O que satisfac... more En este artículo se estudia el modelado global de un sistema de absorción BrLi-H 2 O que satisface las necesidades de climatización de un aula de un centro formación en la localidad murciana de Puerto Lumbreras. Este sistema utiliza un conjunto de colectores solares para satisfacer las necesidades térmicas del generador de vapor de la máquina de absorción. Para la simulación dinámica del sistema se ha utilizado el programa TRNSYS. El local a climatizar se ha modelado utilizando el subprograma de TRNSYS llamado PREBID. En el trabajo se presta especial atención al modelado de la máquina de absorción mediante redes neuronales que posteriormente ha sido implementado en TRNSYS y se plantean algunas conclusiones como consecuencia del estudio realizado. PALABRAS CLAVE: Modelado de sistemas de absorción, transmisión de calor, energía solar, refrigeración solar, redes neuronales.