Experimental investigation of multi-scale turbulent eddy adjustment in personal gasper flow with wedges

Cui Xujia; Tang Zhanqi; Jiang Nan; Liu Junjie

doi:10.11729/syltlx20170110

Volume 32 Issue 2

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Article Navigation > Journal of Experiments in Fluid Mechanics > 2018 > 32(2): 68-73

Cui Xujia, Tang Zhanqi, Jiang Nan, et al. Experimental investigation of multi-scale turbulent eddy adjustment in personal gasper flow with wedges[J]. Journal of Experiments in Fluid Mechanics, 2018, 32(2): 68-73. doi: 10.11729/syltlx20170110

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Experimental investigation of multi-scale turbulent eddy adjustment in personal gasper flow with wedges

doi: 10.11729/syltlx20170110

Cui Xujia^1
,,
Tang Zhanqi^{1, 2},
Jiang Nan^{1, 2
,
,},
Liu Junjie³

1.
Department of Mechanics, School of Mechanical Engineering, Tianjin University, Tianjin 300354, China
2.
Tianjin Key Laboratory of Modern Engineering Mechanics, Tianjin 300354, China
3.
School of Environmental Science and Engineering, Tianjin University, Tianjin 300354, China

Received Date: 2017-08-22
Rev Recd Date: 2017-11-17
Publish Date: 2018-04-25

Abstract

Abstract

In aircraft cabin, the personal gasper plays a significant role in the environment control system. It improves the thermal comfort of passengers and enhances the ventilations and heat exchanges. However, the personal gasper currently in use always brings about uncomfortable draft sensation to the passenger's head. In this paper, the personal gasper is optimized by fixing wedges with different sizes at the nozzle, so that it can adjust and control the multi-scale turbulent eddy structures in the jet flow filed and reduce the uncomfortable draft sensation. The constant-temperature anemometer with the hot-wire probe was employed to finely measure the turbulent jet flow field with high time resolution and evaluate the turbulent level of the personal gasper with wedges. The acquired time series of the instantaneous velocity are decomposed by wavelet analysis to extract the multi-scale turbulent eddy structures, and the effects with and without wedges of different sizes are compared. The 5mm wedges structure is highlighted, which has the most optimal effect and the most comfortable sensation to passengers. By the adjustment and control of wedges, the momentum, energy, mass exchanges of the turbulent jet flow are enhanced, the turbulent level is reduced, the draft sensation deceases and the comfortability is improved.
- aircraft cabin,
- jet flow,
- personal gasper,
- constant-temperature anemometer,
- wavelet analysis

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References(17)

References

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