A new local pressure loss coefficient model of a duct tee junction applied during transient simulation of a HVAC air-side system. Issue 1 (2nd January 2018)

• Record Type: Journal Article
• Authors: Wang, Qiujian; Pan, Yiqun; Zhu, Mingya; Huang, Zhizhong; Xu, Peng
• Is Part Of: Journal of building performance simulation. Volume 11:Issue 1(2018)
• Page Start: 113
• Page End: 127
• Publication Date: 2018-01-02
• Subjects: HVAC air-side system -- system pressure-and-flow coupling -- local pressure loss coefficient -- uniform design -- feature weighted SVR; 690.0113
• DOI: 10.1080/19401493.2017.1288762
• Languages: English
• ISSNs: 1940-1493

Abstract

Abstract : Most of the local pressure loss coefficient (LPLC) models for duct fittings used in heating, ventilation and air conditioning (HVAC) air-side system transient simulations are simplified. The LPLCs are defined as having a constant value at the rated flow condition or as having a polynomial function of the flow ratio (or velocity ratio). To determine the influence of these simplifications, this study used a diverging tee junction as an example. First, we performed CFD calculations to generate a new LPLC dataset and trained a data-driven model using feature weighted support vector regression (FWSVR) combined with particle swarm optimization (PSO-FWSVR). Finally, we compared this new LPLC model with the two traditional models at the level of both individual junction and air-side system. The results show that the accuracy of the new model is greatly improved and the LPLC model can have a significant impact on the system operation condition.