Design and implementation of a modulating test plant to assess the performance of innovative cross-flow heat recovery units for air conditioning system: Preliminary results

Nowadays global warming has increased consciousness of the dangers of energy wastefulness: in the last 50 years the temperature of the Earth's surface rose by approximately 1 °C. The building sector is responsible for a very high percentage of world carbon emissions and with the increasing of the request for comfort, heating, ventilation and air conditioning, buildings energy consumption is rapidly growing. Consequently, it appears fundamental the role played by the improvement of buildings energy performance within global policies of emissions reduction. In this context an increasing attention is given to the energy waste reduction in tertiary sector: bars, offices, restaurants, meetings, shops, school buildings, gyms and in general in the buildings in which the minimization of the energy dissipation is requested. The present study is part of the NANOFANCOIL project (POR-FESR 2014-2020): one of the objectives was the design and implementation of a modulating test plant to assess the performance of innovative cross-flow heat recovery units for air conditioning system. This experimental setup was mainly composed by two climatic chambers that enabled to simulate the environmental conditions of interest. The temperature could vary from -20°C to 0°C and from 10°C to 30°C for the cold and the hot chamber, respectively (i.e. the outdoor and the indoor environment). Moreover, the climatic chamber that simulates the indoor environment could be controlled also in terms of humidity thanks to a steam humidifier that guaranteed 5 kg/h of vapour. Preliminary results about the heat transfer behaviour of a cross-flow heat recovery unit (air-to-air) for controlled mechanical ventilation systems that employs mini-channels in order to increase performance and reduce size and costs are presented here.