Fault Diagnosis Method for High-Pressure Common Rail Injector Based on IFOA-VMD and Hierarchical Dispersion Entropy

The normal operation of high-pressure common rail injector is one of the important prerequisites for the healthy and reliable operation of diesel engines. Therefore, this paper studies the high-precision fault diagnosis method for injectors. Firstly, this paper chooses VMD to adaptively decompose the common rail fuel pressure wave. The biggest difficulty in VMD decomposition is the need to manually set the internal combination parameters K and α. In order to overcome this shortcoming, this paper proposes an improved fruit fly search. The variational mode decomposition method of the algorithm, with the energy growth factor e as the objective function, can adaptively decompose the multi-component signal into superimposed sub-signals. In addition, based on the analytic hierarchy process and dispersion entropy, hierarchical dispersion entropy is proposed to obtain a comprehensive and accurate complexity estimation of time series. Then, a fault diagnosis scheme for high-pressure common rail injector based on IFOA-VMD and HDE is proposed. Finally, using the engineering test data, the method is compared with other methods. The proposed method appears, based on the numerical examples, to be better from both a computational and classification accuracy point of view.

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Research on a small sample fault diagnosis method for a high-pressure common rail system

Advances in Mechanical Engineering ◽

10.1177/16878140211046103 ◽

2021 ◽

Vol 13 (9) ◽

pp. 168781402110461

Author(s):

Liangyu Li ◽

Su Tiexiong ◽

Fukang Ma ◽

Yu Pu

Keyword(s):

Neural Network ◽

High Pressure ◽

Fault Diagnosis ◽

Bp Neural Network ◽

Small Sample ◽

Common Rail ◽

Common Rail System ◽

Rail System ◽

Diagnosis Method ◽

High Pressure Common Rail

In the fault diagnosis of high-pressure common rail diesel engines, it is often necessary to face the problem of insufficient diagnostic training samples due to the high cost of obtaining fault samples or the difficulty of obtaining fault samples, resulting in the inability to diagnose the fault state. To solve the above problem, this paper proposes a small-sample fault diagnosis method for a high-pressure common rail system using a small-sample learning method based on data augmentation and a fault diagnosis method based on a GA_BP neural network. The data synthesis of the training set using Least Squares Generative Adversarial Networks (LSGANs) improves the quality and diversity of the synthesized data. The correct diagnosis rate can reach 100% for the small sample set, and the iteration speed increases by 109% compared with the original BP neural network by initializing the BP neural network with an improved genetic algorithm. The experimental results show that the present fault diagnosis method generates higher quality and more diverse synthetic data, as well as a higher correct rate and faster iteration speed for the fault diagnosis model when solving small sample fault diagnosis problems. Additionally, the overall fault diagnosis correct rate can reach 98.3%.

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Study on the leakage of plunger pair under static condition in high-pressure common rail injector considering deformation effect

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

10.1177/09544070211065607 ◽

2021 ◽

pp. 095440702110656

Author(s):

Zhenbo Gao ◽

Yong Zhang ◽

Dandan Wang

Keyword(s):

High Pressure ◽

Physical Properties ◽

Thickness Distribution ◽

Physical Property ◽

Static Condition ◽

Flow Equation ◽

Common Rail ◽

Plunger Pair ◽

Common Rail Injector ◽

High Pressure Common Rail

Plunger pair is the key component of high pressure common rail injector and its sealing performance is very important. Therefore, it is of great significance to study the leakage mechanism of plunger pair. Under static condition, the high-pressure fuel flow in the gap of the plunger pair caused the deformation of the plunger pair structure and the temperature rise of fuel. For a more comprehensive and accurate study, the effect of deformation, including elastic deformation and thermal expansion, the physical properties of fuel, including density, viscosity and specific heat capacity, as well as the influence of plunger posture in the plunger sleeve, including concentric, eccentric, and inclination condition, are considered in this paper. Firstly, the mathematical models including Reynolds equation, film thickness equation, non-isothermal flow equation, parametric equation of fuel physical property, and section velocity equation are established. The numerical analysis based on finite difference method for the solution of these models is given, which can simultaneously solve for the fuel film pressure distribution, temperature distribution, thickness distribution, distribution of fuel physical properties, and leakage rate. The models are validated by comparing the calculated leakage rates with the measurements. The effects under different posture of plunger are discussed too. Some of the conclusions provided good guidance for the design of high-pressure common rail injector.

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Finite Element Analysis of High-Pressure Common-Rail Injector Body

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.199-200.579 ◽

2011 ◽

Vol 199-200 ◽

pp. 579-582 ◽

Cited By ~ 1

Author(s):

Ju Yan Liu ◽

Zhi Xia He ◽

Qian Wang ◽

Yun Long Huang

Keyword(s):

Finite Element Analysis ◽

Finite Element ◽

High Pressure ◽

Optimization Design ◽

Material Selection ◽

Common Rail ◽

Injection System ◽

Element Analysis ◽

Common Rail Injector ◽

High Pressure Common Rail

The high pressure common rail injection System is one of the most advanced technologies for the diesel engine to reduce fuel consumption exhaust emissions. While the design of the high pressure common rail injector is the key for the whole system. Considering that the working pressure of fuel in the injector, a more accurate injector body model was established with the modeling software Pro/Engineer in this study. Finite element analysis technology in Ansys software was applied to calculate the strength of injector body of the high pressure common rail system under different injection pressures. And then the rationality of structure parameters and material selection of the injector body can be analyzed and verified. The research conclusions can provide the theoretical basis for the optimization design of the injector.

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