Experimental and Numerical Investigations on the Local Direct Leakage Process of Rotary Regenerative Air Preheater

Zhu, Hua; Li, Dechao; Pu, Henglin; Wang, Limin; He, Ya‐Ling; Bu, Yufan; Che, Defu

doi:10.3390/app10041523

Cited by 7 publications

(5 citation statements)

References 22 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Hernandez and Parlos [14] used power spectral density to analyze the frequency domain of motor current and power signal and analyze the current characteristics of motor stator under different mechanical faults of centrifugal pump and realized the fault diagnosis of centrifugal pump cavitation and impeller wear. Zhu et al [15] studied that the sealing performance is enhanced by increasing the spacing of adjacent sealing sheets. Sakthivel et al [16] presented the use of decision tree algorithm for fault diagnosis through statistical feature extracted from vibration signals of good and faulty conditions.…”

Section: Introductionmentioning

confidence: 99%

Analysis of Vibration Characteristics of Centrifugal Pump Mechanical Seal under Wear and Damage Degree

Luo

Zhang

Fan

et al. 2021

Shock and Vibration

View full text Add to dashboard Cite

Mechanical seal is a kind of shaft sealing equipment. Face wear is one of the main causes of mechanical seal failure. Mechanical seal condition is also related to the reduction of energy consumption and carbon emission. Therefore, we need to detect the centrifugal pump seal condition. At present, vibration signal is a common method for fault monitoring and diagnosis of centrifugal pump. In this paper, the vibration signal under the condition of damaged centrifugal pump seal is measured by studying the characteristics of vibration signal after the end face damage of centrifugal pump. Statistical indicators such as RMS and kurtosis were taken to analyze the average energy and shock wave energy of vibration signal. The time-frequency characteristics of vibration signal are analyzed by frequency spectrum. The results show that there are a large extent variation of vibration amplitude in the direction of base and axis and a weak variation of vibration amplitude in the direction of radial and vertical. With the increasing of flow rate, the RMS of vibration signal falls at first, then keeps steady, and mounts at last when the flow rate is over the design flow rate. It can be shown from the time-frequency spectrum that there is a shock wave and pause signals caused by the shock wave, which are reflected by the higher frequency band components of the vibration signal that can provide a reference to the diagnosis of the occurrence of damaged mechanical seal. From the analysis, the energy of vibration signal is related to the running condition, we can find that the occurrence of mechanical seal wear makes the centrifugal pump to produce high-frequency vibration signal, and the axial vibration is the strongest and the instability in the fluid makes the vibration signal produce high amplitude characteristics. Analyzing the vibration signal characteristics of centrifugal pumps with damaged mechanical seal is of great significance to find the mechanical seal failure of the centrifugal pumps and adjust the operating parameters.

show abstract

Section: Introductionmentioning

confidence: 99%

Analysis of Vibration Characteristics of Centrifugal Pump Mechanical Seal under Wear and Damage Degree

Luo

Zhang

Fan

et al. 2021

Shock and Vibration

View full text Add to dashboard Cite

show abstract

“…This study presents an enhanced relational equation to offer a more precise account of leakage behavior while examining the impact of the multi-seal system under varying circumstances. Building upon this, Zhu et al [13] conducted a qualitative analysis, employing a geometrical model of localized leakage of a rectangular body with a constant cross-section. They investigated the impact of operating parameters and seal structure parameters on direct leakage.…”

Section: Introductionmentioning

confidence: 99%

A Novel Numerical Simulation Study of Air Leakage in Rotary Air Preheaters Based on Rotor Thermal Deformation

Li,

Wei,

Fan

et al. 2024

Processes

View full text Add to dashboard Cite

Thermal deformation of the rotor is a critical factor leading to radial air leakage in rotary air preheaters. However, previous studies have not comprehensively established the correlation between rotor thermal deformation during thermal operation and radial air leakage. This study addresses this gap by introducing a novel model for calculating radial air leakage, incorporating the thermal deformation of the rotor. To achieve this, we selected a three-section rotary air preheater from a 330 MW coal-fired unit boiler for investigation. This research begins by constructing a heat transfer–structure coupled numerical simulation model using Fluent and ANSYS Workbench. This model is employed to analyze the thermal deformation of the rotor under varying unit power generation loads. This paper meticulously examines the thermal deformation patterns of the rotor in diverse circumstances, explores their impact on air leakages, and provides a comprehensive analysis of air leakage fluctuations in different ducts. The influence of rotor thermal deformation on the local radial leak characteristics is ultimately established. The results indicate that incorporating the impact of preheater thermal deformation into the examination of preheater air leakage enhances the model’s capacity to accurately simulate values of leakage distribution at various cell clearances. This research concludes by offering recommendations for effectively managing hot end radial air leakage in preheater systems, providing valuable insights for the design and adjustment of sealing systems.

show abstract

“…Zhu et al. 29 investigated the effects of the gap size, the pressure difference, the spacing between the adjacent sealing sheets, the number and bending angle of the sealing sheets on the direct leakage in order to predict air leakage with higher accuracy.…”

Section: Introductionmentioning

confidence: 99%

Modification of rotary air preheater toward achieving extended life-span utilizing porous media approach: A case study

Hajebzadeh¹,

Ansari²

2021

Proceedings of the Institution of Mechanical Engineers, Part A:

View full text Add to dashboard Cite

The main goal of this study is to achieve the extended operating life of the rotary regenerative air pre-heater (Ljungström) of Bandar Abbas power plant by modifying operational parameters by decreasing the corrosion. To achieve this goal, a three-dimensional CFD simulation of the Ljungström is carried out, utilizing the thermal non-equilibrium porous media model. Temperatures are validated against measured data from the power plant with a maximum relative error of 5.54% on the Celsius scale, and mass flow rates are validated with a maximum relative error of −5.25%. The effect of the Ljungström key parameters including the rotational speed, cold layer material, inlet air/flue gas temperature, and mass flow rate, are analyzed in presence of leakages and neglecting it, using porous media approach. The leakage effect is investigated considering radial and axial/peripheral clearances. Finally, a simulation is performed by applying feasible improved parameters extracted from the above analyses considering the effect of all parameters together in presence of leakages, which shows a 6.14% improvement in the Ljungström effectiveness, reducing the total leakage to about one-third of the actual model and eliminating any corrosion.

show abstract

Experimental and Numerical Investigations on the Local Direct Leakage Process of Rotary Regenerative Air Preheater

Cited by 7 publications

References 22 publications

Analysis of Vibration Characteristics of Centrifugal Pump Mechanical Seal under Wear and Damage Degree

Analysis of Vibration Characteristics of Centrifugal Pump Mechanical Seal under Wear and Damage Degree

A Novel Numerical Simulation Study of Air Leakage in Rotary Air Preheaters Based on Rotor Thermal Deformation

Modification of rotary air preheater toward achieving extended life-span utilizing porous media approach: A case study

Contact Info

Product

Resources

About