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Energy and environmental implications of a refrigeration cycle are largely conditioned by the choice of condensing system. Conventional solutions transfer heat to water, and recirculated through cooling towers or to atmospheric air through a dry condenser. While the use of cooling towers means less energy consumption due to lower pressure in the condenser, a number of environmental implications are questioning their installation. Mainly, it represents an emission of chemicals or microorganisms to the atmosphere as Legionella. The dry and adiabatic fluid cooler works as a standard fluid dry cooler enhancing the dry cooler's capacity with adiabatic pre-cooling of the air intake. The ambient dry bulb temperature is reduced as the air passes through an evaporative pad especially designed to humidify and cool the air (Figure.1). The main objective of this study is to experimentally investigate the thermal performance of a dry and adiabatic fluid cooler. With the experimental data, a thermal model will be developed in order to compare the energy implications arising from the replacement of traditional systems (dry condenser and cooling towers) by condensing air coolers with adiabatic pre-cooling. ; The construction of the prototype has been sponsored by the Regional Government of the Comunidad Valenciana, through the Project GV/2011/072. The instrumentation used to conduct experimental work has been funded through the Project "Estudio energético de un sistema alternativo para la condensación en ciclos de refrigeración: el aero-refrigerador con preenfriamiento adiabático" from Convocatoria 2009 de Proyectos Bancaja-UMH para grupos precompetitivos

Introducing an air pre-cooler step before an air cooler system have been proved to improve the global efficiency of a cooling setup. Several authors have studied the mass and the heat exchanges of an air stream and the water sprayed inside an adiabatic cooling pad. However, these previous studies present their results and correlations as functions of experimental dependent parameters. Therefore, the aim of this study is to develop a numerical modeling capable of characterizing the behavior of an air pre-cooling stage without the need of previous experimental tests, allowing an accurate initial study when designing an air cooler installation. Several numerical models and simulation tests have been developed by our researching group in order to get a proper approximation of the problem, and the employment of previous experimental data allowed the model validation in terms of pressure drop and air cooling efficiency. As a result, a numerical model is defined, validated, and compared with existing empirical correlations models as a first step to determine the best possible cooling pad configuration in every air cooling setup as a function of the pad geometry, air and water flow rates, with an only numerical simulation. ; The authors acknowledge the financial support received from the Spanish Government, through Projects ENE2013-48696-C2-1-R and C2-2-R as well as by the FEDER (FondoEuropeo de Desarrollo Regional)

Moisture control has become an important fact for the last years. It has influence on human health and comfort, as well as the quality of certain services and processes. Therefore, it plays an important role for many industries, storage systems, transport and the preservation of products. For this reason, air-conditioning systems are integrating a dehumidifier device called desiccant wheel. The desiccant wheel is in charge of reducing the moisture caused by the process air and requires a hot spot for regeneration. This hot spot can be supported by solar thermal energy. This study evaluates the thermal potential of the ventilation and cooling system in a PV modules' installation. It is done according to the exploitation of the thermal energy transferred to the refrigerant as support to the hot spot, contributing to the regeneration of the desiccant wheel. For this to happen, an experimental installation has been developed, which consists of two inclined PV modules, with an air-flow channel below them. This system enables PV cells to refrigerate, thus improving the electric performance as well as making use of the residual heat generated from this process. One of the two modules is disposed of a series of plates interspersed in its cooling channel, with the aim of modifying the air flow, rising its residence time below the module and making the increase in air temperature more significant. Natural and forced convection have been tested at several air speeds for different irradiance conditions and ambient temperatures. This study deals with the analysis of the thermal potential of these installations under different conditions and its possible applications to the regeneration of desiccant wheels. ; This investigation has been funded by the Education, Culture and Sport Ministry of the government of Spain and by the FEDER European funding, through the ENE2013-48696-C2-2-R project.