Understanding the Dynamics and Control of a Turbulent Impinging Jet via Pulsation and Swirl Using Large Eddy Simulation

2010 ◽  
pp. 325-341
Author(s):  
Naseem Uddin ◽  
Sven Olaf Neumann ◽  
Bernhard Weigand
Keyword(s):  
Large Eddy Simulation ◽  
Impinging Jet ◽  
Eddy Simulation ◽  
Large Eddy ◽  
Dynamics And Control ◽  
And Control

A comparative turbulent flow study of unconfined orthogonal and oblique slot impinging jet using large-eddy simulation

2020 ◽  
Vol 32 (9) ◽  
pp. 095116
Author(s):  
Shashikant Pawar ◽  
Devendra Kumar Patel ◽  
Mukul Bisoi ◽  
Subhransu Roy
Keyword(s):  
Large Eddy Simulation ◽  
Turbulent Flow ◽  
Impinging Jet ◽  
Eddy Simulation ◽  
Large Eddy ◽  
Flow Study

Analysis and Optimization of Turbulent Mixing With Large Eddy Simulation

2006 ◽  
Author(s):  
Ying Huai ◽  
Amsini Sadiki
Keyword(s):  
Large Eddy Simulation ◽  
Turbulent Mixing ◽  
Optimization Procedure ◽  
Impinging Jet ◽  
Computational Domain ◽  
Original Design ◽  
Mixing Processes ◽  
Eddy Simulation ◽  
Large Eddy ◽  
Practical Engineering

In this work, Large Eddy Simulation (LES) has been carried out to analyze the turbulent mixing processes in an impinging jet configuration. To characterize and quantify turbulent mixing processes, in terms of scalar structures and degree of mixing, three parameters have been basically introduced. They are “mixedness parameter”, which represents the probability of mixed fluids in computational domain, the Spatial Mixing Deficiency (SMD) and the Temporal Mixing Deficiency (TMD) parameters for characterizing the mixing at different scalar scale degrees. With help of these parameters, a general mixing optimization procedure has then been suggested and achieved in an impinging jet configuration. An optimal jet angle was estimated and the overall mixing degree with this jet angle reached around six times more than the original design. It turns out that the proposed idea and methodology can be helpful for practical engineering design processes.

Large Eddy Simulation of Round Impinging Jets With Large Stand-Off Distance

2014 ◽  
Author(s):  
Mehrdad Shademan ◽  
Vesselina Roussinova ◽  
Ron Barron ◽  
Ram Balachandar
Keyword(s):  
Large Eddy Simulation ◽  
Flow Characteristics ◽  
Impinging Jet ◽  
Impinging Jets ◽  
Vortical Structures ◽  
Nozzle Height ◽  
Eddy Simulation ◽  
Large Eddy ◽  
The Mean ◽  
Good Agreement

Large Eddy Simulation (LES) has been carried out to study the flow of a turbulent impinging jet with large nozzle height-to-diameter ratio. The dynamic Smagorinsky model was used to simulate the subgrid-scale stresses. The jet exit Reynolds number is 28,000. The study presents a detailed evaluation of the flow characteristics of an impinging jet with nozzle height of 20 diameters above the plate. Results of the mean normalized centerline velocity and wall shear stress show good agreement with previous experiments. Analysis of the flow field shows that vortical structures generated due to the Kelvin-Helmholtz instabilities in the shear flow close to the nozzle undergo break down or merging when moving towards the plate. Unlike impinging jets with small stand-off distance where the ring-like vortices keep their interconnected shape upon reaching the plate, no sign of interconnection was observed on the plate for this large stand-off distance. A large deflection of the jet axis was observed for this type of impinging jet when compared to the cases with small nozzle height-to-diameter ratios.

Large eddy simulation of coherent structure of impinging jet

2005 ◽  
Vol 14 (2) ◽  
pp. 150-155 ◽  
Author(s):  
Mingzhou Yu ◽  
Lihua Chen ◽  
Hanhui Jin ◽  
Jianren Fan
Keyword(s):  
Large Eddy Simulation ◽  
Coherent Structure ◽  
Impinging Jet ◽  
Eddy Simulation ◽  
Large Eddy

PIV experiment and large eddy simulation of turbulence characteristics in a confined impinging jet reactor

2019 ◽  
Vol 27 (1) ◽  
pp. 10-20 ◽  
Author(s):  
Miao Liu ◽  
Zhengming Gao ◽  
Yongjiu Yu ◽  
Zhipeng Li ◽  
Jing Han ◽  
...  
Keyword(s):  
Large Eddy Simulation ◽  
Impinging Jet ◽  
Turbulence Characteristics ◽  
Eddy Simulation ◽  
Large Eddy

Very Large Eddy Simulation of Flow and Heat Transfer in a Pulsating Impinging Jet

2020 ◽  
Author(s):  
Fangyuan Liu ◽  
Junkui Mao ◽  
Xingsi Han ◽  
Zhaoyang Xia
Keyword(s):  
Heat Transfer ◽  
Nusselt Number ◽  
Large Eddy Simulation ◽  
Impinging Jet ◽  
Core Region ◽  
Wall Jet ◽  
The Core ◽  
Eddy Simulation ◽  
Large Eddy ◽  
Pulsating Jets

Abstract The steady impinging jets applied in turbomachine have been comprehensively studied but the pulsating jets still need to be further researched. The flow field and heat transfer characteristics of pulsating impinging jet impinging on a flat plate have been simulated using the improved very large eddy simulation established with SST k–ω model. Two time-mean Reynolds numbers (6,000 and 23,000) in the conditions of frequency = 10Hz and steady state at the constant jet–to–surface distance (6D) were considered. The velocity, vortices, and Nusselt number distributions on the plate surface were investigated to emphasize on the vortex structures in the flow and its relation to the heat transfer. The investigation has revealed the advantage of the improved very large eddy simulation for predicting the dynamical generating process of flow structures in pulsating jets. Calculated results showed pairs of vortices were organized and induced from the jet exit, and propagated along with the jet region periodically. The vortices grew with the entrainment towards the ambient fluid and resulted in accelerated interaction in the wall jet region. Meanwhile, the vortices had strong interaction with the core region and weakened velocity in the core region. Results showed that the time–mean local Nusselt number of pulsating jet was lower in the stagnation region at both investigated Re numbers but not reduced in the wall jet region.

Sign in / Sign up

Export Citation Format

Share Document