دانلود رایگان مقاله تاثیر رفتار تقاضای ناهمزمان بر کولینگ بالا

Abstract

The cooling demands of different zones in an air conditioning (AC) system are different (with large discrepancies) even at the same moment, and the degree of variance changes with time. This asynchronous behavior of demand greatly influences the overcooling degree in multiple zone AC systems. This paper describes the asynchronous demand quantitatively and reveals its relationship with the overcooling degree in a multiple zone AC system. The Lorenz curve and Gini index are introduced in this study and used to describe the demand characteristics. Two typical multiple zone AC systems, namely, constant air volume (CAV) and variable air volume (VAV) systems, are considered as examples, and their overcooling degree under different demand profiles are analyzed. Under different asynchronous demands, the overcooling degree in the CAV system changes from 1 to 3.5, while that in the VAV system changes from 1 to 1.5. In this paper, the influence of the regulation ability of the AC system on energy consumption is also discussed. This paper presents a new perspective to study the demand pattern and explores the method to reduce the overcooling phenomenon in multiple zone AC systems.

6. Conclusions

In this paper, the important influence of asynchronous demands on the operation of the multiple zone AC systems was discussed. The study aimed to describe the asynchronous demand feature quantitatively and to identify its relationship with the degree of overcooling in multiple zone AC systems. The main conclusions of this work are as follows: 1 The asynchronous behavior of the demands greatly influences the degree of overcooling in multiple zone AC systems. The asynchronous demand behavior is reflected in the differences in the cooling demands (with large discrepancies) at the same moment, and the degree of variance changes with time. 2 The Lorenz curve and Gini index are introduced in this paper to describe the asynchronous demands quantitatively. Some clarification and conversion are applied to the index system to fit the characteristics of the cooling demands in a multiple zone AC system. Case studies were conducted to verify the effectiveness of the application of the Lorenz curve and Gini index. 3 The CAV and VAV systems are considered as example to reveal the influence of the asynchronous demand feature on system overcooling. The differences in the Gini index between the supply and demand sides are presented. For different Gini indexes of the demand sides, the degree of overcooling in the CAV system changes from 1 to 3.5, while in the VAV system, the value ranges from 1 to 1.5.