| Stratified air conditioning applied to high ceiling building is a technique of significant energy efficiency and economical profits. High ceiling industrial plants are steadily on the increase, and are becoming an important place for the application of this technique.By searching and reading a lot of correlative scientific literature, and through investigating and analyzing correlative engineering projects, a clear idea of the history, present situation, developing direction and existing issues of the application research of this technique at home and abroad has been gained; and a typical kind of high ceiling machinery plants have been chosen as the experiment object for studying various issues on the application of stratified air conditioning to this kind of plants. This is of great importance for advancing the application of this stratified air conditioning technique, and the results of this experiment are of important value for correlative engineering projects.With the aid of internal existing practical results for high ceiling building, this master degree dissertation theoretically analyzes the energy efficiency and application feasibility of this technique in summer conditions, and the results show that the energy could be saved for 38.7%.Based on the theoretical analyses, the experiment model has been built according to the theory of similarity, and the plan for the experiment has been worked out. In this experiment, Ar number has been adopted as the criteria of similarity, the model has been designed and made according to the geometric scale of 1/3.5, and the experiment equipments have been chosen for the model. The model experiment study has been carried out in three different seasons: summer, transitional season and winter. Its main purpose is to study the air flow performance and air distribution performance within the space (especially in work area) in this kind of plants, to ascertain the effect of stratified air conditioning, to find out the relationships between air distribution performance and different factors, and to explore optimum set of parameters which could save energy and ensure the effect of "stratification". In the model experiment for summer conditions, the influences of several factors (e.g. the height of outlets, the distance between two outlets, supply air velocity, supplyair temperature, diameter of supply air outlets and air supply mode) on air distribution performance within the space have been discussed. The results of model experiment have showed that supply air velocity and diameter of supply air outlets play significant roles on air distribution performance within the occupied space. For summer conditions, 6.5m/s should be chosen as the supply air velocity, 19oC should be chosen as the supply air temperature, and the size of nozzles should be slightly large.In the model experiment for transitional seasons, the influences of different operation conditions on indoor air parameters have been measured and analyzed. And the experiment results show that unhandled outdoor air may be used as supply air, 6.5m/s or above may be kept as the supply air velocity, and the size of nozzles may be reduced. Based on the model experiment of stratified air conditioning in summer conditions, the model experiment for winter heating conditions has been carried out in view of transversal heating air curtain, and through the experiment study on air distribution properties within the space (especially in conditioned zone), issues on application feasibility and common laws of stratified air conditioning in winter conditions in high ceiling plants are discussed. The experimental results show that the transversal heating air curtain could offer the "stratification" effect and control the buoyant heating jet, so it could realize the stratified heating. For winter heating conditions, 6.5m/s should be chosen as the supply air velocity, 28oC should be chosen as the supply air temperature, and the size of nozzles should be reduced.In this model experiment study, through li...
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