scholarly journals Double-Drum Test Bench for Variable Load Transfer Simulation by Electromechanical Inertia Compensation

Sensors ◽  
2019 ◽  
Vol 19 (19) ◽  
pp. 4322
Author(s):  
Zhichao Xing ◽  
Guoye Wang ◽  
Zhangpeng Gong ◽  
Shudong Zhang ◽  
Dongxin Xu ◽  
...  

To improve the accuracy and actual road equivalence of vehicle performance testing using test benches, a double-drum test bench that meets the test requirements of vehicle control system prototypes and in-use vehicles was designed. Dynamic models of the single-wheel test bench and the vehicle test bench were established, and mechanisms were theoretically analyzed for single-wheel variable adhesion and vehicle load transfer for equivalent testing using the variable placement angle. The mechanism of electromechanical inertia compensation was studied to realize stepless simulation of vehicle inertia and simulate dynamic load while braking. The simulation model of the vehicle test bench system was established based on MATLAB/Simulink. Simulations were carried out to verify the anti-lock braking system (ABS) performance test functionality of the test bench under high adhesion, bisectional, and low adhesion conditions. Referring to the simulation conditions, ABS tests under actual test bench and road conditions were carried out. Results demonstrated that the mechanism of variable load transfer simulation by electromechanical inertia compensation improves the equivalent accuracy compared to that of its road test equivalent, verifying the feasibility of the simulation mechanism. This study could help further improve the accuracy and reduce the cost of vehicle performance testing, thus greatly benefitting the vehicle development and testing industry.

Author(s):  
Tina Toburen ◽  
Allen Kephart ◽  
Rhonda Walker

Nearly every power plant in the US must undergo annual Relative Accuracy Test Audits (RATA testing) to confirm the values reported by their continuous emission monitoring systems (CEMS). In order to perform a RATA test, the plant must operate at one or more stable loads for a number of hours. Depending on the type of unit and fuel, the required load levels for RATA testing can range from low, mid and high loads for coal-fired units to a single (normal) load for oil and gas fired units or four loads (from partial load to maximum load) for units utilizing 40 CFR Part 75 Appendix E alternative monitoring systems. Many plants operate in a dispatch environment where the plant is not in control of their load from hour to hour, and some even from minute to minute, such as those operating under Automatic Generation Control (AGC). Scheduling plant loads for the RATA testing must often be done far in advance and can come at a high price when factoring in fuel costs. Because it can be a significant undertaking to schedule the loads for a series of RATA tests, it makes economic sense to schedule other testing also requiring unit stability concurrently with the RATA tests. One of the most important tests that fits this category is performance testing for plant capacity and/or heat rate. Many plants are now required to perform capacity and/or heat rate demonstrations on a periodic basis to support their power purchase agreements or transmission reliability requirements. But even plants without performance test requirements can benefit from gathering performance related data during RATA testing. For plants dispatched based on demonstrated heat rates, understanding the heat rate impact of operating in AGC or at partial loads is essential. Awareness of expected heat rate is also vital for plants that must nominate their fuel consumption requirements in advance. If the RATA test loads are planned correctly, performance data collected during the RATA test periods can be used not only to fulfill required demonstrations for capacity and heat rate, but also to determine the actual annual degradation (recoverable and non-recoverable) observed for the plant equipment. Test data can also be used to build or update performance forecasting tools for dispatch purposes. Depending on the complexity of the RATA testing, multiple load points may be available (from minimum to maximum load) which can provide data on fuel consumption at various loads, supporting fuel purchasing and planning requirements for the plant. This paper intends to outline the value of coordinating annual performance tests with RATA tests in terms of manpower, load scheduling and fuel consumption. This paper will also discuss a number of issues that may arise when coordinating multiple tests — which could be performed by numerous independent parties, as well as the additional benefits which can be gained by collecting adequate performance data during RATA test periods.


2014 ◽  
Vol 701-702 ◽  
pp. 666-674 ◽  
Author(s):  
Kui Ning Li ◽  
Shuai Chen

Based on the methods and standards related to both domestic and overseas air conditioning unit performance testing, a new air conditioning unit performance test bench for measuring refrigerating capacity has been developed. The test bench, which includes removable exterior environment simulation room and interior environment simulation room, applies air enthalpy method to measure refrigerating capacity of air conditioning unit. The experiment result shows that exterior environment simulation room can save 50% construction cost by using removable room. Its room temperature has high accuracy and stability by using hot air of air conditioning unit and exterior air, which can save 50%-60% energy consumption. The accuracy of testing Bench is less than 4%, which is better than the national standard GB/T 19842-2005.


Author(s):  
Amir Golalipour ◽  
Varun Veginati ◽  
David J. Mensching

In the asphalt materials community, the most critical research need is centered around a paradigm shift in mixture design from the volumetric process of the previous 20-plus years to an optimization procedure based on laboratory-measured mechanical properties that should lead to an increase in long-term pavement performance. This study is focused on advancing the state of understanding with respect to the value of intermediate temperature cracking tests, which may be included in a balanced mix design. The materials included are plant-mixed, laboratory-compacted specimens reheated from the 2013 Federal Highway Administration’s (FHWA’s) Accelerated Loading Facility (ALF) study on reclaimed asphalt pavement/reclaimed asphalt shingle (RAP/RAS) materials. Six commonly discussed intermediate temperature (cracking and durability) performance testing (i.e., Asphalt Mixture Performance Tester [AMPT] Cyclic Fatigue, Cantabro, Illinois Flexibility Index Test [I-FIT], Indirect Tensile Cracking [ITC, also known as IDEAL-CT], Indirect Tensile Nflex, and Texas Overlay Test) were selected for use in this study based on input from stakeholders. Test results were analyzed to compare differences between the cracking tests. In addition, statistical analyses were conducted to assess the separation among materials (lanes) for each performance test. Cyclic fatigue and IDEAL-CT tests showed the most promising results. The ranking from these two tests’ index parameters matched closely with ALF field performance. Furthermore, both showed reasonable variability of test data and they were successful in differentiating between different materials.


Author(s):  
Shane E. Powers ◽  
William C. Wood

With the renewed interest in the construction of coal-fired power plants in the United States, there has also been an increased interest in the methodology used to calculate/determine the overall performance of a coal fired power plant. This methodology is detailed in the ASME PTC 46 (1996) Code, which provides an excellent framework for determining the power output and heat rate of coal fired power plants. Unfortunately, the power industry has been slow to adopt this methodology, in part because of the lack of some details in the Code regarding the planning needed to design a performance test program for the determination of coal fired power plant performance. This paper will expand on the ASME PTC 46 (1996) Code by discussing key concepts that need to be addressed when planning an overall plant performance test of a coal fired power plant. The most difficult aspect of calculating coal fired power plant performance is integrating the calculation of boiler performance with the calculation of turbine cycle performance and other balance of plant aspects. If proper planning of the performance test is not performed, the integration of boiler and turbine data will result in a test result that does not accurately reflect the true performance of the overall plant. This planning must start very early in the development of the test program, and be implemented in all stages of the test program design. This paper will address the necessary planning of the test program, including: • Determination of Actual Plant Performance. • Selection of a Test Goal. • Development of the Basic Correction Algorithm. • Designing a Plant Model. • Development of Correction Curves. • Operation of the Power Plant during the Test. All nomenclature in this paper utilizes the ASME PTC 46 definitions for the calculation and correction of plant performance.


Author(s):  
Tomas Gro¨nstedt ◽  
Markus Wallin

Recent work on gas turbine diagnostics based on optimisation techniques advocates two different approaches: 1) Stochastic optimisation, including Genetic Algorithm techniques, for its robustness when optimising objective functions with many local optima and 2) Gradient based methods mainly for their computational efficiency. For smooth and single optimum functions, gradient methods are known to provide superior numerical performance. This paper addresses the key issue for method selection, i.e. whether multiple local optima may occur when the optimisation approach is applied to real engine testing. Two performance test data sets for the RM12 low bypass ratio turbofan engine, powering the Swedish Fighter Gripen, have been analysed. One set of data was recorded during performance testing of a highly degraded engine. This engine has been subjected to Accelerated Mission Testing (AMT) cycles corresponding to more than 4000 hours of run time. The other data set was recorded for a development engine with less than 200 hours of operation. The search for multiple optima was performed starting from more than 100 extreme points. Not a single case of multi-modality was encountered, i.e. one unique solution for each of the two data sets was consistently obtained. The RM12 engine cycle is typical for a modern fighter engine, implying that the obtained results can be transferred to, at least, most low bypass ratio turbofan engines. The paper goes on to describe the numerical difficulties that had to be resolved to obtain efficient and robust performance by the gradient solvers. Ill conditioning and noise may, as illustrated on a model problem, introduce local optima without a correspondence in the gas turbine physics. Numerical methods exploiting the special problem structure represented by a non-linear least squares formulation is given special attention. Finally, a mixed norm allowing for both robustness and numerical efficiency is suggested.


1981 ◽  
Author(s):  
Duane E. Johnson ◽  
Thomas E. Austin ◽  
William F. Van Ostrand

2021 ◽  
Vol 8 (1) ◽  
pp. 59-64
Author(s):  
Almuzakkir . ◽  
Muhammad . ◽  
Adi Setiawan

Fuel is something that is very important in everyday life. Almost every human being needs fuel to meet their needs and support their activities, for example cooking in household needs. Currently, fossil fuels or fuel oil (BBM) are still widely used to meet demand, however, it should be noted that fossil fuels or fuel oil (BBM) are non-renewable natural resources. The biomass rocket stove is one of the modern stove innovations that uses biomass energy as the main energy source. Rocket stoves are designed to increase fuel efficiency with thermal efficiency, a combination of the increased combustion efficiency and heat transfer associated with burning briquette fuel. The purpose of this research is to design and manufacture rocket stove fired with coconut and bamboo biomass for household needs as well as developing methods and equipment for performance testing of rocket stoves. In this study, several steps were carried out, including designing a rocket furnace, selecting biomass fuel and testing the performance of a rocket furnace. From the design of the biomass stove, it is noteworthy that the design with two holes makes the combustion air easily enters and makes combustion in the furnace more perfect and efficient. Water boiling test using three types of solid fuels with the cold start condition suggested that the highest thermal efficiency was coconut fronds with a value of 38% and the lowest thermal efficiency was found from coconut shell combustion, i.e. 22%. During hot start test, the highest thermal efficiency was obtained from coconut fronds firing with a value of 41%. Moreover, with simmer water boiling test method, firing the rocket stove with coconut fronds showed the highest thermal efficiency with a value of 37%. Keywords: Rocket Stoves, Coconut Fronds and Shells, Bamboo, Thermal Efficiency, .Water Boiling Tests.


2021 ◽  
Vol 2021 ◽  
pp. 1-13
Author(s):  
Guodong Zhai ◽  
Xujie Qin ◽  
Xing Yang

As a renewable energy source, wind energy has received more and more attention, and the wind power industry has also been advocated and developed by countries all over the world. In the production and use of wind turbines, the design and manufacturing technology of wind turbine bearings is very important. In order to ensure the reliable operation of the wind power main bearing after installation and realize the longest life of it, this paper designs a bearing test bench that can test the performance of the wind power main bearing. It can analyze the temperature, displacement, load, and moment of the key parts of the 5 MW wind power main shaft bearing. The solid modeling of the experimental platform was carried out using the 3D modeling software SolidWorks. Hydraulic loading system and test monitoring system are designed to realize the drive and control of the test bench. Through the established mathematical model, the central load of the hub is converted into the axial cylinder load and the radial cylinder load of the test bench to simulate the actual working conditions of the tested bearing. The test results show that the test bench meets various loading requirements and can reliably complete the task of testing wind power main bearings.


Sign in / Sign up

Export Citation Format

Share Document