scholarly journals Modeling and Simulation of Aviation Engine Ignition Spark Frequency Disorder

2015 ◽  
Vol 9 (1) ◽  
pp. 193-199 ◽  
Author(s):  
Shi Xudong ◽  
Li Hongguang ◽  
Wang Ruowen ◽  
Xu Meng
Keyword(s):  
Mathematical Model ◽  
Fault Diagnosis ◽  
Modeling And Simulation ◽  
Circuit Simulation ◽  
Aircraft Engine ◽  
Safety And Reliability ◽  
Fault Mechanism ◽  
The Mathematical Model ◽  
Ignition Device

Igniter is an important part of aircraft engine, which should be reliable to ensure safety. Spark frequency disorder is common fault to the aviation ignition device, and it is great hidden danger to the aircraft engine. To guarantee the safety and reliability of aviation igniter, the fault mechanism of the aviation ignition spark frequency disorder is researched in this paper. The factors which will result in spark frequency disorder are studied, and the mathematical model of the ignition circuit and circuit simulation are presented, which lays the foundation for the follow-up research on the design of aviation ignition and the fault diagnosis.

Modelling and Simulation of NO2 Dispersion Phenomenon in Atmosphere by Analytical-Experimental Methods

2008 ◽  
Vol 59 (10) ◽  
Author(s):  
Delia Perju ◽  
Harieta Pirlea ◽  
Gabriela-Alina Brusturean ◽  
Dana Silaghi-Perju ◽  
Sorin Marinescu
Keyword(s):  
Mathematical Model ◽  
Nitrogen Dioxide ◽  
Modeling And Simulation ◽  
Human Health ◽  
Experimental Methods ◽  
Negative Effects ◽  
Real Situation ◽  
Experimental Values ◽  
The Mathematical Model

The European laws and recently the Romanian ones impose more and more strict norms to the large nitrogen dioxide polluters. They are obligated to continuously improve the installations and products so that they limit and reduce the nitrogen dioxide pollution, because it has negative effects on the human health and environment. In this paper are presented these researches made within a case study for the Timi�oara municipality, regarding the modeling and simulation of the nitrogen dioxide dispersion phenomenon coming from various sources in atmosphere with the help of analytical-experimental methods. The mathematical model resulting from these researches is accurately enough to describe the real situation. This was confirmed by comparing the results obtained based on the model with real experimental values.

scholarly journals New “Full-Bridge Buck Inverter–DC Motor” System: Steady-State and Dynamic Analysis and Experimental Validation

Electronics ◽  
2019 ◽  
Vol 8 (11) ◽  
pp. 1216 ◽  
Author(s):  
Eduardo Hernández-Márquez ◽  
Carlos Alejandro Avila-Rea ◽  
José Rafael García-Sánchez ◽  
Ramón Silva-Ortigoza ◽  
Magdalena Marciano-Melchor ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Steady State ◽  
Motor System ◽  
Circuit Simulation ◽  
Dc Motor ◽  
Matlab Simulink ◽  
Duty Cycles ◽  
System Variables ◽  
The Mathematical Model ◽  
Steady State Stability

A mathematical model of a new “full-bridge Buck inverter–DC motor” system is developed and experimentally validated. First, using circuit theory and the mathematical model of a DC motor, the dynamic behavior of the system under study is deduced. Later, the steady-state, stability, controllability, and flatness properties of the deduced model are described. The flatness property, associated with the mathematical model, is then exploited so that all system variables and the input can be differentially parameterized in terms of the flat output, which is determined by the angular velocity. Then, when a desired trajectory is proposed for the flat output, the input signal is calculated offline and is introduced into the system. In consequence, the validation of the mathematical model for constant and time-varying duty cycles is possible. Such a validation of this mathematical model is tackled from two directions: (1) by circuit simulation through the SimPowerSystems toolbox of Matlab-Simulink and (2) via a prototype of the system built by using Matlab-Simulink and a DS1104 board. The good similarities between the circuit simulation and the experimental results allow satisfactorily validating the mathematical model.

MODELING AND SIMULATION OF AUTOMOBILE ANTI-LOCK BRAKING SYSTEM BASED ON SIMULINK

2012 ◽  
Vol 11 (02) ◽  
pp. 99-106 ◽  
Author(s):  
XIAOKAN WANG ◽  
QIONG WANG
Keyword(s):  
Mathematical Model ◽  
Modeling And Simulation ◽  
Pid Controller ◽  
Control Module ◽  
Braking Performance ◽  
Braking System ◽  
The Mathematical Model

This article establishes the mathematical model of automobile anti-lock braking system (ABS) in the Simulink environment and tracks the research and simulation of the ABS established mathematical model, which is based on the control module with the PID controller. From the simulation curve, we can verify automobile ABS with good braking performance and direction maneuverability.

scholarly journals Fault Diagnostic Methodology for Grid-Connected Photovoltaic Systems

2021 ◽  
Vol 2 (2) ◽  
pp. 10-30
Author(s):  
Proenza Y. Roger ◽  
Camejo C. José Emilio ◽  
Ramos H. Rubén
Keyword(s):  
Mathematical Model ◽  
Fault Diagnosis ◽  
Solar Energy ◽  
False Alarm ◽  
False Alarm Rate ◽  
Real System ◽  
Photovoltaic Systems ◽  
Energy Research ◽  
Santiago De Cuba ◽  
The Mathematical Model

This research focuses on the design of a fault diagnosis methodology to contribute to the improvement of efficiency, maintainability and availability indicators of Grid-Connected Photovoltaic Systems. To achieve this, we start from the study of the mathematical model of the photovoltaic generator, then, a procedure is performed to quantify the operational losses of the photovoltaic generator and adjust the mathematical model of this to the real conditions of the system, through a polynomial adjustment. A real system of nominal power 7.5 kWp installed in the Solar Energy Research Center of the province of Santiago de Cuba is used to evaluate the proposed methodology. Based on the results obtained, the proposed approach is validated to demonstrate that it successfully supervises the system. The methodology was able to detect and identify 100% of the simulated failures and the tests carried out had a maximum false alarm rate of 0.22%, evidencing its capacity.

scholarly journals An operation optimization method of a fully mechanized coal mining face based on semi-physical virtual simulation

2019 ◽  
Vol 7 (1) ◽  
pp. 147-163 ◽  
Author(s):  
Hengbo Shi ◽  
Jiacheng Xie ◽  
Xuewen Wang ◽  
Juanli Li ◽  
Xing Ge
Keyword(s):  
Mathematical Model ◽  
Coal Mining ◽  
Production Efficiency ◽  
Optimization Method ◽  
Hydraulic Support ◽  
Tracking Model ◽  
Low Efficiency ◽  
Mining Face ◽  
The Mathematical Model

AbstractA mathematical hydraulic support self-tracking model for three-machine cooperative mining is proposed to address low efficiency and difficulties in strategy evaluation of a fully mechanized coal face. The proposed model uses the coordinates and traction speed of the shearer to calculate the frequency of the circular hydraulic support and realize the coordinated operation of the three-machine mining technology. A unity3d hardware-in-the-loop simulation experimental hearer and hydraulic support platform was used to validate the model of autonomous follow-up. The results indicate that collaborative control of coal mining allowed for an efficiency 3.76% higher than under automatic operation mode and 46.03% higher than under manual control; thus, The mathematical model provided an improved production efficiency of the fully mechanized mining face. The mathematical model also provides a more intelligent and reliable security support, and improves the intelligent level of hydraulic support follow-up control.

Modeling and Simulation of a Co-current Rotary Dryer

2016 ◽  
Vol 12 (2) ◽  
pp. 189-194 ◽  
Author(s):  
Zhi-gang Huang ◽  
Yun-xuan Weng ◽  
Nan Fu ◽  
Zong-qiang Fu ◽  
Dong Li ◽  
...  
Keyword(s):  
Experimental Data ◽  
Mathematical Model ◽  
Moisture Content ◽  
Mathematical Models ◽  
Modeling And Simulation ◽  
Air Temperature ◽  
Good Accuracy ◽  
Rotary Dryer ◽  
Simulation Results ◽  
The Mathematical Model

Abstract Mathematical models including mass and energy conservation were developed in order to predict the outlet particles temperature and moisture. As the inlet air temperature increased, the outlet particles temperature increased as well and the outlet particles moisture decreased quickly. The outlet particles temperature and moisture changed a little as a function of the speed of rotation at the low inlet air temperature, while the outlet particles temperature and moisture increased very apparently with the speed of rotation increased at the high inlet air temperature. The error of the simulation results compared to the experimental data showed good accuracy for particles temperature and moisture content. The mathematical model performs well to predict the outlet particles temperature and moisture content.

The Modeling and Simulation of UAV Pneumatic Launch System

2013 ◽  
Vol 299 ◽  
pp. 27-30
Author(s):  
Xiao Long Liu ◽  
Chuang Na Xia ◽  
Sheng Gang Ma
Keyword(s):  
Mathematical Model ◽  
Modeling And Simulation ◽  
Unmanned Aerial Vehicle ◽  
Future Development ◽  
Theoretical Foundation ◽  
Bond Graph ◽  
Inflation Pressure ◽  
Work Process ◽  
Aerial Vehicle ◽  
The Mathematical Model

This paper is based on the Bond Graph method to establish the mathematical model of UAV (Unmanned Aerial Vehicle) pneumatic launch system, simulates its work process through using MATLAB software, analyzes the influence of changing air tank inflation pressure, air tank volume on launch performance, and draws some important conclusions, which can provide a theoretical foundation for the future development and improvement of the system.

Study on Spatial Nonlinear Vibration Characteristics of Cables with a Particular Constraint

2015 ◽  
Vol 724 ◽  
pp. 222-229
Author(s):  
Jian Mei Liu ◽  
Bin Di You
Keyword(s):  
Mathematical Model ◽  
Nonlinear Vibration ◽  
Simulation Analysis ◽  
Solution Space ◽  
Dimensional Solution ◽  
Resonance Modes ◽  
Safety And Reliability ◽  
Object Of Study ◽  
The Galerkin Method ◽  
The Mathematical Model

In order to study the nonlinear vibration problems of cable with a particular constraint, the mathematical model for the object of study should be established firstly with the elastic mechanics method. In order to obtain the mathematical model of differential form, the Galerkin method is used to make the mathematical model discrete and modal truncation, so the infinite dimensional solution space of the mathematical model can be transformed into the finite dimensional one. Main factors influencing the vibration of the cable system are analyzed, and the simulation analysis about the effects of various parameters on frequency is carried out. The analysis results show that the internal resonance modes may exist, and provide a theoretical basis for improving the safety and reliability of laying cables in actual conditions.

Wind Generator Model for Fault Diagnosis

2013 ◽  
Vol 347-350 ◽  
pp. 1430-1434
Author(s):  
Wei Wang ◽  
Hai Fang Yu ◽  
Chang Fu Zheng ◽  
Yan Shi Zhao
Keyword(s):  
Mathematical Model ◽  
Fault Diagnosis ◽  
Wind Turbine ◽  
Synchronous Generator ◽  
Equation Model ◽  
Generator Voltage ◽  
Drive Chain ◽  
The Moment ◽  
Tower Vibration ◽  
The Mathematical Model

In order to make a diagnosis of wind turbine failure, the mathematical model of the wind turbine should be prepared. This model can provide a theoretical basis for fault diagnosis. establishing the mathematical model of the main part of the generator being discussed on theoretical ,including the tower vibration, wind wheel and drive chain, the moment of inertia of the wind turbine and the synchronous generator voltage equation model in dq coordinate system. Its main focus on the demand for wind turbine fault diagnosis.

scholarly journals Aortic pulse wave velocity as a prognostic tool of hypertension in obesity

2019 ◽  
Vol 25 (4) ◽  
pp. 416-422
Author(s):  
M. A. Druzhilov ◽  
O. Y. Druzhilova ◽  
T. Y. Kuznetsova
Keyword(s):  
Mathematical Model ◽  
Pulse Wave Velocity ◽  
Wave Velocity ◽  
Pulse Wave ◽  
Blood Pressure Monitoring ◽  
Aortic Pulse Wave Velocity ◽  
Prognostic Assessment ◽  
Glucose Profiles ◽  
The Mathematical Model

Objective. The aim was to assess the role of the aortic pulse wave velocity (PWVao) as additional predictor of hypertension (HTN) development in men with obesity.Design and methods. 526 men without HTN (according to ambulatory blood pressure monitoring (ABPM) without therapy) (age 45,1 ± 5,0 years) with abdominal obesity (waist circumference > 94 cm) and SCORE < 5 %, without cardiovascular diseases and diabetes mellitus were examined. The diagnostic tests included the lipid and glucose profiles, creatinine, albuminuria evaluation, echocardiography, carotid ultrasound, bifunctional ABPM (portable recorder BPLab®) with average daily PWVao assessment. Patients with subclinical carotid atherosclerosis (n = 98) were excluded from the follow-up. Follow-up examination including ABPM was conducted on average after 46,3 ± 5,1 months.Results. Data of 406 subjects were available for analysis. HTN defined as average daily BP ≥ 130/80 mm Hg was found in 157 patients (38,7 %). The mathematical model included the following parameters: age, body mass index, mean daily systolic BP and mean daily PWVao. Among these predictors a PWVao was characterized by the highest standardized regression coefficient (0,461, p < 0,001). The area under the ROC-curve was 0,945 (95 % confidence interval 0,920–0,971, р < 0,001). At the selected cut-off point of PWVao 7,7 m/s the sensitivity and specificity of the model were 85,4 % and 96,8 %, respectively.Conclusions. The mathematical model for assessing the probability of HTN development in patients with obesity which includes the PWVao is characterized by a high overall percentage of correct classifications with comparability with actual data. Bifunctional ABPM with the PWVao evaluation in patients with obesity is the preferred method for additional prognostic assessment.

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