Studies on the "ventilation effectiveness" and modification of the ventilation system in the waiting hall of a railway station.

The concept of ventilation effectiveness for mechanical ventilation of an airspace is reviewed and associated parameters for describing the performance of ventilation systems are described. The idea is applied to a study of the thermal environment in the waiting hall of a railway station. Two ventilation schemes: one with a ventilation system only and the other with an air-conditioning system were considered. The proposed air-conditioning system would provide air at a temperature only 5 °C below the ambient but with a higher air circulation rate. This would reduce the amount of energy used for environmental protection compared to more conventional systems providing full air-conditioning. It is found that using such a scheme it is possible to provide a better thermal environment using less energy than with a full air-conditioning system.