Influence Mechanism of Ambient Air Parameters on the Rotational Stall of an Axial Fan
Abstract
:1. Introduction
2. Materials and Methods
2.1. Geometric Model and Grid Division
2.2. Governing Equations and Turbulence Model
2.3. Boundary Conditions
3. Results
3.1. Overall Characteristics of Axial-Flow Fan
3.2. Time-Domain Characteristics of Fan Outlet Static Pressure
3.3. Dynamic Characteristics of the Flow Field inside the Moving Blade before and after Rotational Stall Occurs
3.3.1. Static Pressure Distribution Patterns inside the First-Stage Impeller before and after Stall
3.3.2. Distribution Patterns of Relative Velocity Streamlines before and after Stall
3.3.3. Distribution Patterns of Turbulent Kinetic Energy before and after Stall
3.3.4. The Influence of Temperature Changes on Turbulent Kinetic Energy during Stall Occurrence
4. Conclusions
- (1).
- Numerical simulations were performed on axial-flow fans employed within the plant, analyzing the flow rate and pressure variations under various temperatures at the fan’s design conditions. Through the manipulation of air parameters as individual variables and employing neural networks for data fitting, it was discerned that the fan’s flow rate and outlet pressure exhibit dependency on both temperature and the nature of the working fluid. Delving further, these dependencies are intricately linked to the density and dynamic viscosity of the working fluid. Specifically, the mass flow rate and outlet pressure of the fan demonstrate a positive correlation with the density of the working fluid, while displaying a negative correlation with its dynamic viscosity.
- (2).
- Unsteady simulations were used to achieve the phenomenon of rotating stalls in an axial flow fan at low flow rates, obtaining the total pressure and flow characteristics curves of the fan. The peak outlet pressure was reached at around 80 m³/s for air at various densities. When the flow was further reduced by adjusting the valve, a stall occurred after a slight decrease in flow rate, reducing the volumetric flow to 55 m³/s. As the air temperature increases (i.e., density decreases), both the maximum outlet pressure and the outlet pressure at the stall decrease, the mass flow rate decreases, the power output capability reduces, and the stall margin decreases.
- (3).
- An analysis of the internal flow field of the rotor was performed at various critical moments preceding and following stall occurrence, focusing on static pressure distribution, streamlines, and turbulent kinetic energy. Observations revealed that the stall cell initiates at the blade tip, propagating through the rotor passage. During this progression, a localized backflow phenomenon manifests at the blade tip region, aligning with the direction of propagation. Subsequently, the extent and intensity of the backflow gradually escalate, culminating in the complete obstruction of the passage. Eventually, the backflow induced by the stall cell weakens rapidly, allowing the passage to exit the stall, thereby restoring the flow field to its normal state.
Author Contributions
Funding
Data Availability Statement
Conflicts of Interest
References
- Day, I.J. Stall, Surge and 75 Years of Research. In American Society of Mechanical Engineers Digital Collection; ASME: New York, NY, USA, 2015. [Google Scholar]
- Dodds, J.; Vahdati, M. Rotating Stall Observations in a High Speed Compressor—Part I: Experimental Study. J. Turbomach. 2015, 137, 051002. [Google Scholar] [CrossRef]
- Dodds, J.; Vahdati, M. Rotating Stall Observations in a High Speed Compressor—Part II: Numerical Study. J. Turbomach. 2015, 137, 051003. [Google Scholar] [CrossRef]
- Subbarao, R.; Govardhan, M. Effect of Axial Spacing between the Components on the Performance of a Counter Rotating Turbine. Int. J. Fluid Mach. Syst. 2013, 6, 170–176. [Google Scholar] [CrossRef]
- Chang, D.; Tavoularis, S. Effect of the Axial Spacing between Vanes and Blades on a Transonic Gas Turbine Performance and Blade Loading. Int. J. Turbo Jet-Engines 2013, 30, 15–31. [Google Scholar] [CrossRef]
- Zhang, L.; He, R.; Wang, X.; Zhang, Q.; Wang, S. Study on Static and Dynamic Characteristics of an Axial Fan with Abnormal Blade under Rotating Stall Conditions. Energy 2019, 170, 305–325. [Google Scholar] [CrossRef]
- Hu, J.; Li, Q.; Pan, T.; Gong, Y. Numerical Investigations on Stator Hub Initiated Stall in a Single-Stage Transonic Axial Compressor. Aerosp. Sci. Technol. 2018, 80, 144–155. [Google Scholar] [CrossRef]
- Huawei, L.; Fu, C.; Jilin, W.; Zhongqi, W. Flow Field Improvement by Bowed Stator Stages in a Compressor with Different Axial Gaps Under Near Stall Condition. Chin. J. Aeronaut. 2008, 21, 215–222. [Google Scholar] [CrossRef]
- Two-Dimensional Rotating Stall Analysis in a Wide Vaneless Diffuser—Ljevar—2006—International Journal of Rotating Machinery—Wiley Online Library. Available online: https://onlinelibrary.wiley.com/doi/10.1155/IJRM/2006/56420 (accessed on 28 June 2024).
- Khaleghi, H. Stall Inception and Control in a Transonic Fan, Part A: Rotating Stall Inception. Aerosp. Sci. Technol. 2015, 41, 250–258. [Google Scholar] [CrossRef]
- High-Speed Stereoscopic PIV Study of Rotating Instabilities in a Radial Vaneless Diffuser|Experiments in Fluids. Available online: https://link.springer.com/article/10.1007/s00348-010-1030-x (accessed on 28 June 2024).
- Babu Ummiti, M.; Sitaram, N.; Prasad, B.V.S.S.S. Computational Investigation of Effect of Axial Spacing on Blade Row Interaction in a 1½ Stage Axial Flow Turbine. Eng. Appl. Comp. Fluid 2009, 3, 56–70. [Google Scholar] [CrossRef]
- Choi, M.; Smith, N.H.S.; Vahdati, M. Validation of Numerical Simulation for Rotating Stall in a Transonic Fan. J. Turbomach. 2013, 135, 021004. [Google Scholar] [CrossRef]
- Zhang, L.; Zhou, J.; Zuo, S.; An, G.; Lang, J.; Yuan, W. Effect Mechanism of Ambient Air Parameters on the Thermal Performance for Cooling Towers. J. Therm. Sci. Eng. Appl. 2023, 16, 011011. [Google Scholar] [CrossRef]
- Brandstetter, C.; Ottavy, X.; Paoletti, B.; Stapelfeldt, S. Interpretation of Stall Precursor Signatures. J. Turbomach. 2021, 143, 121011. [Google Scholar] [CrossRef]
- Zhang, L.; Zhang, L.; Zhang, Q.; Jiang, K.; Tie, Y.; Wang, S. Effects of the Second-Stage of Rotor with Single Abnormal Blade Angle on Rotating Stall of a Two-Stage Variable Pitch Axial Fan. Energies 2018, 11, 3293. [Google Scholar] [CrossRef]
- Manas, M.P.; Pradeep, A.M. Stall Inception in a Contra-Rotating Fan under Radially Distorted Inflows. Aerosp. Sci. Technol. 2020, 105, 105909. [Google Scholar] [CrossRef]
- Toge, T.D.; Pradeep, A.M. Experimental Investigation of Stall Inception of a Low Speed Contra Rotating Axial Flow Fan under Circumferential Distorted Flow Condition. Aerosp. Sci. Technol. 2017, 70, 534–548. [Google Scholar] [CrossRef]
- Tan, C.S.; Day, I.; Morris, S.; Wadia, A. Spike-Type Compressor Stall Inception, Detection, and Control. Annu. Rev. Fluid Mech. 2010, 42, 275–300. [Google Scholar] [CrossRef]
- Xu, D.; Zhu, H.; Dong, X.; Sun, D.; Sun, X. Theoretical and Experimental Investigation on the Stall Inception of Low-Speed Axial Compressors with Swept Rotor Blades. Aerosp. Sci. Technol. 2023, 142, 108659. [Google Scholar] [CrossRef]
- Chattopadhyay, N.C.; Zahidul Islam Eunus, H.E.M.; Ikram, M.d.I.; Mahmud, R. Compressor Instability: Stall, Surge and Their Control. Appl. Mech. Mater. 2013, 390, 408–413. [Google Scholar] [CrossRef]
- Li, J.; Liu, Y.; Du, J.; Zhang, H. Automatic Stability Control Using Tip Air Injection in a Multi-Stage Axial Flow Compressor. Aerosp. Sci. Technol. 2020, 98, 105707. [Google Scholar] [CrossRef]
- Lu, B.; Zhu, M.; Teng, J.; Qiang, X. Design Strategy of Axial Slot Casing Treatment for a Transonic Compressor Rotor Based on Parametric Analysis. Aerosp. Sci. Technol. 2021, 119, 107142. [Google Scholar] [CrossRef]
- Liu, M.; Zhang, Z.; Liang, Z.; Xiao, H.; Chen, H.; Yang, X.; Shao, C. New Insights into Flow for a Low-Bypass-Ratio Transonic Fan with Optimized Rotor. Energies 2023, 16, 7230. [Google Scholar] [CrossRef]
- Kozakiewicz, A.; Kachel, S.; Frant, M.; Majcher, M. Intake System Performance Stability as a Function of Flow Throttling. Energies 2022, 15, 6291. [Google Scholar] [CrossRef]
- Zhang, L.; Kang, J.; Lang, J.; An, G.; Zhang, Q.; Wang, L.; Wang, Q. Stall Evolution Mechanism of a Centrifugal Compressor with a Wide-Long Vaneless Diffuser. J. Therm. Sci. 2024, 33, 899–913. [Google Scholar] [CrossRef]
- An, G.; Kang, J.; Zou, Y.; Zhang, L.; Lang, J.; Yuan, W.; Zhang, Q. Investigation of the Unsteady Flow in a Transonic Axial Compressor Adopted in the Compressed Air Energy Storage System. J. Energy Storage 2023, 63, 106928. [Google Scholar] [CrossRef]
- Yuan, W.; Zhang, L.; Wang, S.; Zhang, Q. Influence Mechanism of Axial Spacing on Stall Inception of a Two-stage Axial-flow Fan. Chin. J. Power Eng. 2016, 36, 801–809. [Google Scholar]
- An, G.; Kang, J.; Wang, L.; Zhang, L.; Lang, J.; Li, H. Decoupling and reconstruction analysis in a transonic axial compressor using the dynamic mode decomposition method. Physics Fluids 2023, 35, 084120. [Google Scholar] [CrossRef]
- Zhang, L.; Yang, Z.; Sun, E.; Zhang, Q.; An, G.; Yuan, W. Numerical Simulation Study on Influence of Equation of State on Internal Flow Field and Performance of S-CO2 Compressor. J. Therm. Sci. 2024, 33, 888–898. [Google Scholar] [CrossRef]
- Zhang, L.; Zhou, J.; Zuo, S.; Yuan, W.; Zhang, Q. Anti-freezing mechanism of the direct air-cooled system by splitting columns operation. Int. Commun. Heat Mass Transf. 2024, 158, 107883. [Google Scholar] [CrossRef]
Structural Parameters | Numerical |
---|---|
Rotation speed (r/min) | 1490 |
Number of moving blades | 24 |
Number of static blades | 23 |
Inlet diameter (m) | 2.312 |
Outlet diameter (m) | 2.305 |
Rotor diameter (m) | 1.778 |
Hub ratio | 0.668 |
Working Fluid | Temperature (°C) | Density (kg/m3) | Specific Heat Capacity (kJ/(kg⋅K)) | Thermal Conductivity(W/(m⋅K)) | Dynamic Viscosity (10−6 Pa⋅s) |
---|---|---|---|---|---|
Air | −25 | 1.4235 | 1.0058 | 0.0221 | 15.9789 |
−20 | 1.3953 | 1.0058 | 0.0225 | 16.2385 | |
−15 | 1.3681 | 1.0058 | 0.0229 | 16.4962 | |
−10 | 1.342 | 1.0058 | 0.0232 | 16.7519 | |
−5 | 1.3169 | 1.0059 | 0.0236 | 17.0057 | |
0 | 1.2927 | 1.0059 | 0.024 | 17.2576 | |
5 | 1.2694 | 1.006 | 0.0244 | 17.5076 | |
10 | 1.2469 | 1.0061 | 0.0248 | 17.7558 | |
15 | 1.2252 | 1.0063 | 0.0251 | 18.0023 | |
20 | 1.2043 | 1.0064 | 0.0255 | 18.247 | |
25 | 1.184 | 1.0066 | 0.0259 | 18.4899 | |
30 | 1.1644 | 1.0067 | 0.0262 | 18.7312 | |
35 | 1.1455 | 1.0069 | 0.0266 | 18.9708 | |
40 | 1.1272 | 1.0072 | 0.027 | 19.2088 | |
45 | 1.1094 | 1.0074 | 0.0273 | 19.4452 | |
50 | 1.0922 | 1.0077 | 0.0277 | 19.6807 | |
60 | 1.0594 | 1.0083 | 0.0284 | 20.1452 | |
70 | 1.0284 | 1.0089 | 0.0291 | 20.6043 | |
80 | 0.9993 | 1.0097 | 0.0298 | 21.0577 | |
90 | 0.9717 | 1.0105 | 0.0305 | 21.5055 | |
100 | 0.9456 | 1.0115 | 0.0312 | 21.9479 | |
110 | 0.9209 | 1.0125 | 0.0318 | 22.3851 | |
120 | 0.8975 | 1.0136 | 0.0325 | 22.8173 | |
130 | 0.8752 | 1.0148 | 0.0332 | 23.2447 | |
140 | 0.854 | 1.016 | 0.0338 | 23.6673 | |
150 | 0.8338 | 1.0174 | 0.0345 | 24.0853 | |
Flue gas | 150 | 0.8206 | 1.2186 | 0.368 | 24.5014 |
160 | 0.1310 | 1.3325 | 0.381 | 24.9186 |
Monitoring Target | a | b | c | d | R-Square |
---|---|---|---|---|---|
Mass flow rate | 109.4 | −0.2653 | 4.755 × 104 | −2.198 × 10−7 | 0.999 |
Volume flow rate | 84.65 | 0.1053 | −3.678 × 104 | 9.748 × 10−7 | 0.998 |
Outlet pressure | 1.303 × 104 | −63.86 | 0.1475 | 5.29 × 10−6 | 0.996 |
Monitoring Target | R-Square | ||||||
---|---|---|---|---|---|---|---|
Mass flow rate | −1046 | 359.7 | 27.35 | −71.68 | 18.91 | −0.2813 | 0.991 |
Volume flow rate | −0.6882 | −28.14 | −1.205 | −2.389 | 5.783 | 0.05878 | 0.989 |
Outlet pressure | 71,310 | 48,240 | −2146 | −11,780 | −3406 | 40.53 | 0.993 |
Operational Condition | Description |
---|---|
k = 1 | Flow state approaching the design flow rate and far from the occurrence of rotational stall |
k = 0.752, T = 30 | State of incipient stall characterized by the appearance of stall inception |
k = 0.752, T = 50 | State in the process where stall inception develops into mature stall cells |
k = 0.752, T = 80 | State where the stall inception has developed into mature stall cells and stabilized flow |
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Ma, H.; Tang, G.; Wang, C.; Wang, T.; Li, X.; Jia, Y.; Qiu, Y.; Yuan, W.; Zhang, L. Influence Mechanism of Ambient Air Parameters on the Rotational Stall of an Axial Fan. Processes 2024, 12, 1781. https://doi.org/10.3390/pr12081781
Ma H, Tang G, Wang C, Wang T, Li X, Jia Y, Qiu Y, Yuan W, Zhang L. Influence Mechanism of Ambient Air Parameters on the Rotational Stall of an Axial Fan. Processes. 2024; 12(8):1781. https://doi.org/10.3390/pr12081781
Chicago/Turabian StyleMa, Hui, Guangtong Tang, Chaoyang Wang, Tianlong Wang, Xin Li, Yonghui Jia, Yulong Qiu, Wei Yuan, and Lei Zhang. 2024. "Influence Mechanism of Ambient Air Parameters on the Rotational Stall of an Axial Fan" Processes 12, no. 8: 1781. https://doi.org/10.3390/pr12081781