Research On The Air-sending Characteristics Of Fabric Air Dispersion System

Fabric air dispersion system is one of the terminal equipments in air-conditioning system, which made form special polyester material, can be used in both air transmission and air diffusion. The conditioned air can be dispersed to the room by fabric duct permeation, slot along the duct or orifice made in the fabric duct surface. The air dispersion models of fabric duct include porous, slot, slot with porous fabric and orifices, orifices with porous fabric.In this thesis, air dispersion models and basic characteristics of fabric air dispersion system are introduced. In further, based on computational fluid mechanics and heat transfer theory, three different air dispersion physical models respectively using porous and slot to send the air to the target room are established, andκ?εturbulence model and inlet model (and etc.) are used to establish a three dimensional turbulence mathematical model of an air-conditioned room. Using FLUENT, I simulated the sending air characteristics using porous, slot and slot to separate occupied zone and high-temperature zone respectively. The results make clear that fabric air dispersion system using porous and slot model can both lead to good temperature field and velocity field in the air-conditioned room, meets the requirements of HVAC design very well; and, in the same side air supply and return model, whatever in summer and winter, the slot model can make good temperature and velocity field, without hot air floating or cold air falling. It was also found that, if the load of the room was cut to half of the design condition, reduce the sending air volume to half of the design volume can still get good temperature and velocity field in the room, which makes clear that it is possible to use fabric air dispersion system in a VAV system. And, in the simulation we found that sending air using slot to separate occupied zone and high-temperature zone can get excellent results. Based on good design, the slot model of fabric air dispersion system can separate the high-temperature zone and occupied zone effectively and create a good working environment for the indoor workers.