scholarly journals A New Experimental Method of Combined Fatigue of Actual Turbine Disk Mortise Teeth at Elevated Temperature

1996 ◽  
Author(s):  
Rongqiao Wang ◽  
Jingxu Nie
Keyword(s):  
Elevated Temperature ◽  
Experimental Method ◽  
Real Time ◽  
High Frequency ◽  
Local Heating ◽  
Experimental System ◽  
Turbine Disk ◽  
Combined Loading ◽  
Experimental Result ◽  
High Frequency Induction

For studying the L-HCCF of an actual turbine disk mortise teeth at elevated temperature, this paper presents a new experimental system, using actual disk as experimental component, ingeniously achieving the combined loading (simulating low cycle radial centrifugal force and high cycle crosswise vibration of blade), the high-frequency induction local heating (550 °C constant temperature), the control of high cycle vibrating frequency and amplitude, and the crack real-time detection. The experimental result is identical with the practical flight failure. This method can be easily popularized for the L-HCCF studying of many components.

A New Experimental Method to Study Combined Fatigue of Actual Turbine Disk Mortise Teeth at Elevated Temperatures

1997 ◽  
Vol 119 (4) ◽  
pp. 969-972 ◽  
Author(s):  
Rongqiao Wang ◽  
Jingxu Nie
Keyword(s):  
Elevated Temperature ◽  
Temperature Control ◽  
High Frequency ◽  
Elevated Temperatures ◽  
Local Heating ◽  
Experimental System ◽  
Turbine Disk ◽  
Combined Loading ◽  
Experimental Result ◽  
High Frequency Induction

This paper presents a new experimental system to study the L-HCCF of an actual turbine disk mortise teeth at elevated temperature, using an actual disk as experimental component. This system ingeniously achieves combined loading (simulating low cycle radial centrifugal force and high cycle crosswise vibration of blade), high-frequency induction local heating (550°C constant temperature), control of high cycle vibrating frequency and amplitude, and crack real-time detection. The experimental result is identical with the practical flight failure. This method can be easily popularized to study the L-HCCF of many components.

scholarly journals FPGA-Based Implementation of Finite Set-MPC for a VSI System Using XSG-Based Modeling

Energies ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 260 ◽  
Author(s):  
Vijay Kumar Singh ◽  
Ravi Nath Tripathi ◽  
Tsuyoshi Hanamoto
Keyword(s):  
Real Time ◽  
System Development ◽  
Control Strategies ◽  
System Modeling ◽  
Experimental System ◽  
Experimental Result ◽  
Voltage Source ◽  
Primary Concern ◽  
Fpga Design ◽  
Finite Set

Finite set-model predictive control (FS-MPC) is used for power converters and drives having unique advantages as compared to the conventional control strategies. However, the computational burden of the FS-MPC is a primary concern for real-time implementation. Field programmable gate array (FPGA) is an alternative and exciting solution for real-time implementation because of the parallel processing capability, as well as, discrete nature of the hardware platform. Nevertheless, FPGA is capable of handling the computational requirements for the FS-MPC implementation, however, the system development involves multiple steps that lead to the time-consuming debugging process. Moreover, specific hardware coding skill makes it more complex corresponding to an increase in system complexity that leads to a tedious task for system development. This paper presents an FPGA-based experimental implementation of FS-MPC using the system modeling approach. Furthermore, a comparative analysis of FS-MPC in stationary αβ and rotating dq frame is considered for simulation as well as experimental result. The FS-MPC for a three-phase voltage source inverter (VSI) system is developed in a realistic digital simulator integrated with MATLAB-Simulink. The simulated controller model is further used for experimental system implementation and validation using Xilinx FPGA: Zedboard Zynq Evaluation and Development Kit. The digital simulator termed as Xilinx system generator (XSG) provided by Xilinx is used for modeling-based FPGA design.

Rapid Sintering and Synthesis of Nanostuctured FeCrAlSi-Al2O3 Composite by High-Frequency Induction Heating

2011 ◽  
Vol 49 (03) ◽  
pp. 231-236 ◽  
Author(s):  
Song-Lee Du ◽  
Sung-Hun Cho ◽  
In-Yong Ko ◽  
Jung-Mann Doh ◽  
Jin-Kook Yoon ◽  
...  
Keyword(s):  
Induction Heating ◽  
High Frequency ◽  
Al2o3 Composite ◽  
Rapid Sintering ◽  
High Frequency Induction

In-situ compaction and sintering of Al2O3 – GNP nanoparticles using a high-frequency induction system

2018 ◽  
Vol 60 (7-8) ◽  
pp. 727-732
Author(s):  
Uğur Çavdar ◽  
İ. Murat Kusoglu ◽  
Ayberk Altintas
Keyword(s):  
High Frequency ◽  
Induction System ◽  
High Frequency Induction

Design and implementation of decoupled periodic control scheme for a laboratory-based quadruple-tank process

2021 ◽  
pp. 095965182110228
Author(s):  
Jatin K Pradhan ◽  
Arun Ghosh
Keyword(s):  
Real Time ◽  
High Frequency ◽  
Linear Time ◽  
Disturbance Attenuation ◽  
Minimum Phase ◽  
Periodic Control ◽  
Linear Time Invariant ◽  
Control Scheme ◽  
Gain Margin ◽  
Time Invariant

It is well known that linear time-invariant controllers fail to provide desired robustness margins (e.g. gain margin, phase margin) for plants with non-minimum phase zeros. Attempts have been made in literature to alleviate this problem using high-frequency periodic controllers. But because of high frequency in nature, real-time implementation of these controllers is very challenging. In fact, no practical applications of such controllers for multivariable plants have been reported in literature till date. This article considers a laboratory-based, two-input–two-output, quadruple-tank process with a non-minimum phase zero for real-time implementation of the above periodic controller. To design the controller, first, a minimal pre-compensator is used to decouple the plant in open loop. Then the resulting single-input–single-output units are compensated using periodic controllers. It is shown through simulations and real-time experiments that owing to arbitrary loop-zero placement capability of periodic controllers, the above decoupled periodic control scheme provides much improved robustness against multi-channel output gain variations as compared to its linear time-invariant counterpart. It is also shown that in spite of this improved robustness, the nominal performances such as tracking and disturbance attenuation remain almost the same. A comparison with [Formula: see text]-linear time-invariant controllers is also carried out to show superiority of the proposed scheme.

scholarly journals RTLIO: Real-Time LiDAR-Inertial Odometry and Mapping for UAVs

Sensors ◽  
2021 ◽  
Vol 21 (12) ◽  
pp. 3955
Author(s):  
Jung-Cheng Yang ◽  
Chun-Jung Lin ◽  
Bing-Yuan You ◽  
Yin-Long Yan ◽  
Teng-Hu Cheng
Keyword(s):  
Feedback Control ◽  
Real Time ◽  
High Frequency ◽  
Indoor Environment ◽  
Indoor Localization ◽  
Sampling Rate ◽  
Outdoor Environment ◽  
Position Accuracy ◽  
Graph Optimization ◽  
Pose Graph Optimization

Most UAVs rely on GPS for localization in an outdoor environment. However, in GPS-denied environment, other sources of localization are required for UAVs to conduct feedback control and navigation. LiDAR has been used for indoor localization, but the sampling rate is usually too low for feedback control of UAVs. To compensate this drawback, IMU sensors are usually fused to generate high-frequency odometry, with only few extra computation resources. To achieve this goal, a real-time LiDAR inertial odometer system (RTLIO) is developed in this work to generate high-precision and high-frequency odometry for the feedback control of UAVs in an indoor environment, and this is achieved by solving cost functions that consist of the LiDAR and IMU residuals. Compared to the traditional LIO approach, the initialization process of the developed RTLIO can be achieved, even when the device is stationary. To further reduce the accumulated pose errors, loop closure and pose-graph optimization are also developed in RTLIO. To demonstrate the efficacy of the developed RTLIO, experiments with long-range trajectory are conducted, and the results indicate that the RTLIO can outperform LIO with a smaller drift. Experiments with odometry benchmark dataset (i.e., KITTI) are also conducted to compare the performance with other methods, and the results show that the RTLIO can outperform ALOAM and LOAM in terms of exhibiting a smaller time delay and greater position accuracy.

Sign in / Sign up

Export Citation Format

Share Document