Influence of the Internal Structure Type of a Large-Area Lower Exhaust Workbench on Its Surface Air Distribution
Abstract
:1. Introduction
2. Subjects and Methods
2.1. Geometric Models
2.1.1. Models of the Workbench for Structural Research
2.1.2. Model of the Workbench for Experimental Validation
- (1)
- Although the method shown in Figure 2b was the same for both, the bottom plate was inclined in the experimental workbench, while it was horizontal in the numerical simulation workbench with Structure-4.
- (2)
- Although both workbenches were set with five internal slits, the widths of the slits in the experimental workbench were 0.04 m, 0.045 m, 0.05 m, 0.07 m and 0.095 m from left to right, while they were all 0.06 m in the numerical simulation workbench with Structure-4.
- (3)
- To eliminate the influence of the orifice plate on the airflow distribution, the multi-hole orifice plate was not set in the surface of the numerical simulation workbench with Structure-4, while it was set in the surface of the experimental workbench. The diameter of the holes in the multi-hole orifice plate was 2 mm, the spacing between the holes was 2 mm, and the arrangement of the holes was 60° staggered.
2.2. Research Conditions
2.3. The Grid Sensitivity Tests
2.4. Experimental Workbench and Test Methods
3. Results
3.1. Velocity Contours for Differently Structured Workbenches
3.2. Workbench Surface Velocity for Differently Structured Workbenches
3.3. Velocity Vector Maps for Differently Structured Workbenches
3.4. Experimental Validation Results
4. Discussion
5. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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Solver Parameters | Parameter Settings |
---|---|
Solver type | Pressure-based |
Solver velocity formulation | Absolute |
Solver time | Steady |
Viscous model | Standard k-epsilon |
Species transport | Off |
Energy | Off |
Pressure–velocity coupling | SIMPLEC |
Spatial discretization | Second order upwind |
Convergence criterion | 10−6 |
Interaction to plot and store | 1000 |
Wall condition | Stationary wall/No slip |
Boundary Conditions | Parameter Settings |
---|---|
Outlet | Surface of lower exhaust workbench |
Outlet boundary type | Pressure outlet |
Gauge pressure (Pa) | 0 |
Inlet | Air outlet of elbow |
Inlet boundary type | Velocity inlet |
Velocity at inlet (m/s) | –5 |
Material | Air |
Air viscosity (kg/m/s) | 1.81 × 10−5 |
Hydraulic diameter of inlet (m) | 0.48 |
Turbulence intensity of inlet (%) | 3.81 |
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Chen, J.; Jin, L.; Yang, B.; Chen, Z.; Zhang, G. Influence of the Internal Structure Type of a Large-Area Lower Exhaust Workbench on Its Surface Air Distribution. Int. J. Environ. Res. Public Health 2022, 19, 11395. https://doi.org/10.3390/ijerph191811395
Chen J, Jin L, Yang B, Chen Z, Zhang G. Influence of the Internal Structure Type of a Large-Area Lower Exhaust Workbench on Its Surface Air Distribution. International Journal of Environmental Research and Public Health. 2022; 19(18):11395. https://doi.org/10.3390/ijerph191811395
Chicago/Turabian StyleChen, Jianwu, Longzhe Jin, Bin Yang, Zhenfang Chen, and Guoliang Zhang. 2022. "Influence of the Internal Structure Type of a Large-Area Lower Exhaust Workbench on Its Surface Air Distribution" International Journal of Environmental Research and Public Health 19, no. 18: 11395. https://doi.org/10.3390/ijerph191811395