Hainan Wang

Search for another author

Author Description

Ask a Question About This Mathematician

All published works (3)

The Sedimentation Mechanical Properties of Coal and Gangue Particles at Different Granularity Levels

2025-04-30

Chengyong Liu , Wenzhe Gu , Haijun Zhang +6 more

Coal gangue, the primary bulk solid waste generated during coal utilization, requires decarbonization and the enrichment of valuable components such as calcium and magnesium through methods like hydrocyclone separation for … Coal gangue, the primary bulk solid waste generated during coal utilization, requires decarbonization and the enrichment of valuable components such as calcium and magnesium through methods like hydrocyclone separation for comprehensive utilization. This study observed the free-settling behavior of coal gangue particles using a high-speed dynamic image analysis system and analyzed their kinematic characteristics to guide the hydrocyclone separation process. The results indicate that particle size and density significantly influence settling behavior. Fine-grained, low-density particles exhibited more pronounced directional deflection and velocity fluctuations, while high-density coarse particles demonstrated higher settling velocities. Based on terminal velocity, the drag coefficient of fluid resistance acting on particles was calculated. The findings show that high-density coarse particles have larger drag coefficients, likely due to fluid disturbances and the hydrophobic nature of particle surfaces. Additionally, the mechanical properties of settling motion were analyzed, indicating that gravity dominates the settling process of coarse particles, while fine particles are subjected to relatively balanced forces. Furthermore, density variations primarily affect hydrodynamic drag, which is related to the surface properties of particles. Therefore, enhancing the centrifugal force field through cyclone structural optimization is necessary to improve separation precision for fine coal and gangue particles.

Detection of Fan Blade Defects Based on Improved YOLOv8n

2025-02-24

Xu Wang , Wenfeng Xu , Qingyu Cui +4 more

As the core component of the wind turbine, blades are susceptible to deterioration caused by natural environmental factors. This can manifest as erosion, fissures, and gel coat detachment, which collectively … As the core component of the wind turbine, blades are susceptible to deterioration caused by natural environmental factors. This can manifest as erosion, fissures, and gel coat detachment, which collectively impair the efficiency of wind power generation and the safe operation of the turbine. In order to address the issue of low detection accuracy for wind turbine blade defects in complex environments, an enhanced YOLOv8n wind turbine blade defect detection algorithm has been proposed. First, the Large Separable Kernel Attention (LSKA) attention mechanism is introduced into the Spatial Pyramid Pooling Fast (SPPF) module of the backbone network, thereby enhancing the network’s attention and improving the model’s feature extraction capability. Second, the neck employs a weighted bidirectional feature pyramid (Bi-FPN) structure and integrates a P2 small target detection layer, thus enhancing the model’s multi-scale feature fusion capability and improving its small target detection accuracy. Finally, the loss function of the original model is optimized using WIoU, thereby improving the model’s defect detection accuracy. The results of the defect detection experiments on wind turbine blade images demonstrate that the accuracy of the proposed method has been enhanced by 7.9%, the mAP 50 has been improved by 2.6%, and the number of parameters has been reduced by 23%.

Analysis of the 3-omega method for thermal conductivity measurement

2008-12-27

Hainan Wang , Mihir Sen

Common Coauthors

Coauthor	Papers Together
Xiangyun Shi	1
Bo-Long Zhang	1
Yuejin Zhou	1
Mihir Sen	1
Wenzhe Gu	1
Quanzhi Tian	1
Wenfeng Xu	1
Chengyong Liu	1
Qingyu Cui	1
Hao Zhang	1
Haijun Zhang	1
Xu Wang	1
Xiaolong Yin	1
Litong Hao	1
Zhicheng Liu	1

Commonly Cited References

3ω method for specific heat and thermal conductivity measurements

2001-07-01

Lan Lu , Wei Yi , Di Zhang

We present a 3ω method for simultaneously measuring the specific heat and thermal conductivity of a rod- or filament-like specimen using a way similar to a four-probe resistance measurement. The … We present a 3ω method for simultaneously measuring the specific heat and thermal conductivity of a rod- or filament-like specimen using a way similar to a four-probe resistance measurement. The specimen in this method needs to be electrically conductive and with a temperature-dependent resistance, for acting both as a heater to create a temperature fluctuation and as a sensor to measure its thermal response. With this method, we have successfully measured the specific heat and thermal conductivity of platinum wire specimens at cryogenic temperatures, and measured those thermal quantities of tiny carbon nanotube bundles some of which are only ∼10−9 g in mass.

Chat View PDF

Measurement of the thermal conductance of silicon nanowires at low temperature

2007-01-01

Olivier Bourgeois , Thierry Fournier , J. Chaussy

We have performed thermal conductance measurements on individual single crystalline silicon suspended nanowires. The nanowires (130 nm thick and 200 nm wide) are fabricated by e-beam lithography and suspended between … We have performed thermal conductance measurements on individual single crystalline silicon suspended nanowires. The nanowires (130 nm thick and 200 nm wide) are fabricated by e-beam lithography and suspended between two separated pads on Silicon On Insulator (SOI) substrate. We measure the thermal conductance of the phonon wave guide by the 3 method. The cross-section of the nanowire approaches the dominant phonon wavelength in silicon which is of the order of 100 nm at 1K. Above 1.3K the conductance behaves as T3, but a deviation is measured at the lowest temperature which can be attributed to the reduced geometry.

Chat View PDF