Local ventilation sytems: some investigations about comfort levels and energy demands

Efficient ventilation of indoor environments shall guarantee not only a proper oxygen flow for human breathing, but also an effective removal of pollutants released by human metabolism and building materials. Usually, high ventilation rates are adopted to reach these two goals, with a consequent high energy consumption for buiding climatization.
A good compromise between good indoor air quality and energy saving can be achieved by adopting local ventilation systems, such as the so called task ventilation. Local ventilation has turned out to be a very effective way to respond to specific personal requirements and therefore also to improve satisfaction and productivity in working places.
In this paper some local ventilation systems are analysed and compared with the traditional well-mixed ventilation. A small movie theatre is simulated as a test case by using a CFD computer model: this way, local comfort indices as well as energy demands, have been determined for the different ventilation systems, in order to optimize the ventilation strategy.