There is a wide range of ventilative cooling principles, and their application depends on climate and microclimate, building type, ventilation approach and user expectations. Depending on possibilities and limitations in the actual case, the ventilative cooling (VC) system may come out as mechanical, hybrid or natural ventilation and may also be supplemented by other natural cooling technologies like ground cooling, earth-to-air heat exchangers or evaporative cooling.
In design and optimization of ventilative cooling the challenge is to sequentially minimize the cooling load, maximize the VC capacity to remove the load and, as a last step, minimize the electricity consumption of the supplementary cooling systems (if needed).
A design procedure adapted to ventilative cooling design is shown in the Figure 1. A ventilation design procedure consists of different phases: conceptual design phase, basic design phase, detailed design phase and design evaluation consisting of:
- The conceptual design phase for ventilative cooling sets off by setting targets for indoor environment, energy use and cost and by performing an analysis of the ventilative cooling potential of the site taking into account both the climate, the surroundings, as well as overall building characteristics.
- The basic design phase, the internal heat, solar and contaminant loads are estimated on room level and the ventilative cooling system layout is designed.
- The detailed design phase, thermal loads are re-evaluated, and source control options are considered and/or optimized.
- The design evaluation phase, detailed predictions of thermal comfort can be performed to ensure that the design fulfils the targets of the project.
Figure 1: Design procedure for ventilation and ventilative cooling [1]
References
[1] Heiselberg, P., Ventilative Cooling Design Guide, IEA EBC Annex 62, Aalborg University: Aalborg, Denmark, 2018
Posted in: Cooling, Thermal Comfort, Ventilation