Traditional low-energy ventilative cooling systems for modern architecture

Despite the energy-saving potential of using natural ventilation systems such as wind towers, research into determining their passive cooling capacity for providing thermal comfort is limited. In order to confront this subject, a numerical investigation into determining the thermal and ventilation capability of a roof-mounted wind tower integrated with the heat pipe technology was carried out. The water-filled copper heat pipes measuring having an outer diameter of 20mm were systematically arranged in a horizontal orientation. Water was used as the working fluid instead of synthetic refrigerants in order to make the system carbon-neutral alongside maintaining the indoor air quality of the built environment. The three-dimensional Reynolds-Averaged Navier-Stokes (RANS) equations along with the momentum, continuity and energy equations were solved using the commercial Computational Fluid Dynamics (CFD) code for velocity and pressure field simulations. Using the inlet wind speeds varying from 1m/s to 4m/s, the results of the study showed that the proposed cooling system was capable of meeting the regulatory fresh air intake requirements per occupant of 5L/s. In addition, the findings determined that a passive cooling capacity of up to 11K was achievable when the system was subjected to inlet temperatures of 310K or 37°C. The work characterised the sustainable operation of wind tower in delivering energy-free ventilative cooling in regions encompassing hot and dry climatic conditions. The technology presented in this work is currently under an Intellectual Property (IP) protection (GB1321709.6).