Lateral exhaust systems have commonly been applied to capture polluted buoyant jets in many industrial processes, such as casting and metallurgy. Compared with the normal conditions of design manuals, the capture efficiency of a lateral exhaust hood (LEH) is often weakened by two factors in actual processes: the unsteady buoyant jet released from the operating surface, and the plume formed above a high-temperature workpiece placed between the LEH and the operating surface. In this study, through experiments and numerical simulations, a pulsatile phenomenon was found in the velocity and concentration distribution of the unsteady buoyant jet. Results show that the contaminate escape ratio is pulsatile; it rises with the instantaneous increase in the buoyant jet velocity and gradually decreases to a constant value. This study not only reveals the air distribution of pulsating buoyant jet but also analyses the effect of the pulsating buoyant jet and high-temperature plume on lateral ventilation system capture efficiency and provides a possible guidance for future design of new building ventilation technologies.
DevienneRFontaineJRKickaJBonthouxF.Experimental characterization of a plume of passive contaminant above a thermal source: capture efficiency of a fume extraction hood. Ann Occup Hyg2009;
53: 739–748.
2.
WangYCaoZ.Industrial building environment: old problem and new challenge. Indoor Built Environ2017;
26: 1035–1039.
3.
HuangJ-MHsuS-PWuY-LChenH-YWangC-C.The effect of ventilation types on pollutant removal in a large space plant with multiple pollutant sources. Indoor Built Environ2011;
20: 488–500.
4.
CaoCGaoJHouYJieC.Ventilation strategy for random pollutant releasing from rubber vulcanization process. Indoor Built Environ2017;
26: 248–255.
5.
FengZYuCWCaoS-J.Fast prediction for indoor environment: models assessment. Indoor Built Environ2019;
28: 727–730.
6.
CaoS-JRenC.Ventilation control strategy using low-dimensional linear ventilation models and artificial neural network. Build Environ2018;
144: 316–333.
7.
RenCCaoS-J.Implementation and visualization of artificial intelligent ventilation control system using fast prediction models and limited monitoring data. Sustain Cities Soc2020;
52: 101860.
8.
RenCCaoS-J.Development and application of linear ventilation and temperature models for indoor environmental prediction and HVAC systems control. Sustain Cities Soc2019;
51: 101673.
9.
GoodfellowHD.Industrial ventilation design guidebook.
Amsterdam, The Netherlands:
Elsevier, 2001.
10.
ACGIH HA.Industrial ventilation: a manual of recommended practice for design.
Washington, USA:
American Conference of Governmental Industrial Hygienists, 2013.
11.
RodiW.Turbulent buoyant jets and plumes: HMT: the science & applications of heat and mass transfer. Reports, reviews & computer programs.
Amsterdam, The Netherlands:
Elsevier, 2014.
12.
FanL-N.Turbulent buoyant jets into stratified or flowing ambient fluids. Dissertation (Ph.D.), California Institute of Technology, Pasadena, 1967.
13.
MortonBRIbbetsonA.Jets deflected in a crossflow. Exp Therm Fluid Sci1996;
12: 112–133.
14.
KimKKimSYoonS.PIV measurements of the flow and turbulent characteristics of a round jet in crossflow. J Vis2000;
3: 157–164.
15.
MuppidiSMaheshK.Study of trajectories of jets in crossflow using direct numerical simulations. J Fluid Mech2005;
530: 81–100.
16.
RajaratnamNGangadhariahT.Axis of a circular jet in cross-flow. Water Air Soil Pollut1981;
15: 317–321.
17.
AndreopoulosJRodiW.Experimental investigation of jets in a crossflow. J Fluid Mech1984;
138: 93–127.
18.
JiangG-QZhangX-yLiW.Study on round turbulent jet in a cross flow with PIV. Adv Water Sci2002;
13: 588–593.
19.
WeiLJiangG-QXiaoyuanZ.Vortex structures of round turbulent jets in cross-flow. Adv Water Sci2003;
14: 576–582.
20.
SubramanyaKPoreyP.Trajectory of a turbulent cross jet. J Hydraulic Res1984;
22: 343–354.
21.
BursikM.Effect of wind on the rise height of volcanic plumes. Geophys Res Lett2001;
28: 3621–3624.
22.
HanHLLiW.Study on 3-D line buoyant jets in cross flows. J Hydraulic Eng1999;
30: 46–50.
23.
FuY-YWangXHuangCLuoX.Study on the motion of non-isothermal jet under the action of plumes. J Univ Shanghai Sci Technol2008;
30: 387–391.
24.
JunGJianingZFushengG.Velocity and flow rate correction of multiple equal plumes and influence on natural ventilation in high-large spaces. Hv & AC2004; 34(10): 21–28.
25.
ContiniDHaydenPRobinsA.Concentration field and turbulent fluxes during the mixing of two buoyant plumes. Atmos Environ2006;
40: 7842–7857.
26.
IchimiyaKSaikiH.Behavior of thermal plumes from two-heat sources in an enclosure. Int J Heat Mass Transfer2005;
48: 3461–3468.
27.
KriaaWMhiriHLe PalecGBournotP.Numerical study of the interaction between two laminar and coaxial plane jets with variable density in an ambient fluid. Energy Convers Manage2003;
44: 2037–2057.
28.
Baratian-GhorghiZKayeNBKhanAASmithJR.The merging of two unequal axisymmetric parallel turbulent jets. J Hydrodyn2012;
24: 257–262.
29.
HuntGCooperPLindenP.Thermal stratification produced by plumes and jets in enclosed spaces. Build Environ2001;
36: 871–882.
30.
DiezFSangrasRFaethGKwonO.Self-preserving properties of unsteady round buoyant turbulent plumes and thermals in still fluids. J Heat Transfer2003;
125: 821–830.
31.
SangrasRKwonOFaethG.Self-preserving properties of unsteady round nonbuoyant turbulent starting jets and puffs in still fluids. J Heat Transfer2002;
124: 460–469.
32.
YinSLiYSandbergMLamK.The effect of building spacing on near-field temporal evolution of triple building plumes. Build Environ2017;
122: 35–49.
33.
YinSLiYFanYSandbergM.Experimental investigation of near-field stream-wise flow development and spatial structure in triple buoyant plumes. Build Environ2019;
149: 79–89.
34.
JenkinsRMFosterWAJrWirthLS.Numerical analysis of unsteady multiple jet plume interactions. Appl Math Comput1996;
79: 239–247.
35.
ChojnickiKClarkeAPhillipsJAdrianR.Rise dynamics of unsteady laboratory jets with implications for volcanic plumes. Earth Planet Sci Lett2015;
412: 186–196.
36.
ChangJShaoXLiJHuX.A comparison of classical and pulsating jets in crossflow at various Strouhal numbers. Math Probl Eng2017;
2017: 1–14.
37.
SauRMaheshK.Optimization of pulsed jets in crossflow. J Fluid Mech2010;
653: 365–390.
38.
HerwigHMiddelbergG.The physics of unsteady jet impingement and its heat transfer performance. Acta Mech2008;
201: 171.
39.
DurstFHeimUÜnsalBKullikG.Mass flow rate control system for time-dependent laminar and turbulent flow investigations. Meas Sci Technol2003;
14: 893.
40.
HuangYWangYLiuLNielsenPVJensenRLYangX.Performance of constant exhaust ventilation for removal of transient high-temperature contaminated airflows and ventilation-performance comparison between two local exhaust hoods. Energy Build2017;
154: 207–216.
41.
HuangYWangYRenXYangYGaoJZouY.Ventilation guidelines for controlling smoke, dust, droplets and waste heat: four representative case studies in Chinese industrial buildings. Energy Build2016;
128: 834–844.
42.
CroweCRiesebieterH. and An analytical and experimental study of jet deflection in a cross flow. Fluid dynamics of rotor and fan supported aircraft at subsonic speeds, AGARD reprints.
Paris:
NATO. 1967.
43.
ShihT-HLiouWWShabbirAYangZZhuJ.A new k-ɛ eddy viscosity model for high Reynolds number turbulent flows. Comput Fluids1995;
24: 227–238.
44.
El-AminMSunSHeidemannWMüller-SteinhagenH.Analysis of a turbulent buoyant confined jet modeled using realizable k–ɛ model. Heat Mass Transfer2010;
46: 943–960.
