众所周知，传统置换通风（TDV）和地板下空气分配（UFAD）等分层空气分配系统可以提供更好的室内空气质量。本研究考察了TDV和UFAD的几个关键设计参数对空气分配效率的影响。本研究首先回顾了有关TDV和UFAD系统通风性能的文献。因此，选择了六个不同的室内空间和几个设计参数进行参数研究。其中，办公室、餐厅、送风室、送风室、送风室、送风室和送风室为设计参数。本研究在实验上将TDV与使用四种不同扩散器（穿孔TDV扩散器、涡流扩散器、线性扩散器和穿孔扩散器）的UFAD系统进行了比较- 地板扩散器）安装在试验箱中，可以模拟相同尺寸的不同室内空间。两种系统在冷却模式下的通风性能均高于混合系统。此外，具有低高度抛撒器的系统更好。实验数据还用于验证研究分层空气分布的CFD程序。然后，本研究使用经过验证的CFD程序，进一步研究TDV和UFAD系统在不同室内空间的通风性能，以及通过文献综述选择的设计参数。研究发现，办公室、教室、餐厅和零售店的呼吸区空气分配效率为1.1~1.6，车间和礼堂为1.6~2.0。天花板较高的空间（如车间和礼堂）的空气分配效率高于天花板较低的空间。 因此，分层空气分配系统更适合天花板较高的空间。低抛高度的TDV和UFAD的气流分配效率相似，高于高抛高度和混合通风的UFAD。建立了包含102例参数研究结果的数据库。利用该数据库，研究人员开发了一组相关方程，用于通过统计分析计算空气分配效率。如果设计情况特殊，且相关方程无法使用，本研究提出了一个七步指南，用于使用CFD确定TDV和UFAD系统的空气分配效率。单位:双

Stratified air distribution systems such as Traditional Displacement Ventilation (TDV) and Under-Floor Air Distribution (UFAD) have been known to provide better indoor air quality. This investigation examined the influence of several key design parameters of TDV and UFAD in air distribution effectiveness.This investigation first reviewed the literature concerning the ventilation performance of the TDV and UFAD systems. As a result, six different indoor spaces and several design parameters were selected for the parametric study. The indoor spaces were offices, classrooms, restaurants, workshops, retail shops, and auditoriums, while the design parameters were diffuser type, ventilation rate, throw, supply air temperature, and cooling load.This investigation compared experimentally the TDV with UFAD systems that use four different diffusers (perforated TDV diffusers, swirl diffusers, linear diffusers, and perforated-floor-panel diffusers) in a test chamber that can simulate different indoor spaces of the same size. The two systems had higher ventilation performance than the mixing one under cooling mode. Also, the systems with low-height-throw diffusers were better. The experimental data was also used to validate a CFD program for studying stratified air distributions.This investigation then used the validated CFD program to further study the ventilation performance of the TDV and UFAD systems for different indoor spaces and design parameters which were selected through the literature review. The study found that the air distribution effectiveness at breathing zone was at 1.1 ~ 1.6 for offices, classrooms, restaurants and retail shops, and at 1.6 ~ 2.0 for workshops and auditoriums. The spaces with a high ceiling such as workshops and auditoriums had higher air distribution effectiveness than those with a low ceiling. Thus, the stratified air distribution systems are better for spaces with a high ceiling. The air distribution effectiveness for the TDV and UFAD with low throw height was similar and was higher than that of UFAD with high throw height and mixing ventilation.A database was established containing 102 cases of the parametric study results. With this database, the investigation developed a set of correlation equations for calculating air distribution effectiveness through statistical analysis. If a design case is special and the correlation equations cannot be used, this investigation proposed a seven-step guideline for using CFD to determine the air distribution effectiveness of the TDV and UFAD systems.Units: Dual