scholarly journals Designing optimal control maps for diesel engines for high efficiency and emission reduction

2019 ◽  
Author(s):  
Hoang Nguyen Khac ◽  
Kai Zenger
Keyword(s):  
Optimal Control ◽  
Diesel Engines ◽  
Emission Reduction ◽  
High Efficiency

scholarly journals Effect of Green Construction on a Building’s Carbon Emission and Its Price at Materialization

2021 ◽  
Vol 13 (2) ◽  
pp. 642
Author(s):  
Shuangxi Zhou ◽  
Zhenzhen Guo ◽  
Yang Ding ◽  
Jingliang Dong ◽  
Jianming Le ◽  
...  
Keyword(s):  
Greenhouse Gases ◽  
Emission Reduction ◽  
Carbon Emission ◽  
High Efficiency ◽  
Carbon Price ◽  
Carbon Trading ◽  
Construction Companies ◽  
Green Construction ◽  
The World ◽  
Total Price

Buildings consume many resources and generate greenhouse gases during construction. One of the main sources of greenhouse gases is carbon emission associated with buildings. This research is based on the computing rule of carbon emission at the materialization stage. By taking the features of green construction into consideration, quantitative analysis on construction carbon emission was undertaken via Life Cycle Assessment (LCA). Making use of Vensim (a system dynamics software package), we analyzed the amount of carbon emission at the materialization stage and determined the major subsystems affecting the carbon emission, then took into comprehensive consideration the differences of each subsystem’s carbon emission under different construction technologies. Under the mechanism of carbon trade at the materialization stage, the total price of carbon trades remains unchanged, while the trading price of each subsystem is adjusted. Under these conditions, a coefficient for step-wise increases in carbon price was proposed. By establishing such a system of gradient prices, construction companies are encouraged to adopt high-efficiency emission reduction technologies. Meanwhile, the system also provides a reference for the formulation of price-based policies about buildings’ carbon trading, and accelerates the process of energy conservation and emission reduction in China and the world at large.

Research on Throttle Optimal Control of Flipper Jack for Hydraulic Support

2012 ◽  
Vol 503-504 ◽  
pp. 824-827
Author(s):  
Chun Qiang Jia ◽  
Wei Li ◽  
Ling Yu
Keyword(s):  
Optimal Control ◽  
Simulation Model ◽  
High Efficiency ◽  
Hydraulic Support ◽  
Simulation Results ◽  
Amesim Simulation

To solve the problem of support speed of hydraulic support flipper, the match relations between the flipper throttle control and shearer cutting coal speed are analyzed, the AMESim simulation model of the throttle optimal control for hydraulic support flipper jack is established, the simulation results show that flipper can be supported timely by speed optimal control of flipper jack which improve the reliability of the system and provide certain theory basis to meet the miner safety and high efficiency production.

Efficient Human Motion Planning Using Recursive Dynamics and Optimal Control Techniques

1999 ◽  
Author(s):  
Janzen Lo ◽  
Dimitris Metaxas
Keyword(s):  
Optimal Control ◽  
Motion Planning ◽  
Closed Loop ◽  
High Efficiency ◽  
Human Motion ◽  
Lagrangian Formulation ◽  
Planning Problem ◽  
Tree Structures ◽  
Recursive Dynamics ◽  
Minimum Torque

Abstract We present an efficient optimal control based approach to simulate dynamically correct human movements. We model virtual humans as a kinematic chain consisting of serial, closed-loop, and tree-structures. To overcome the complexity limitations of the classical Lagrangian formulation and to include knowledge from biomechanical studies, we have developed a minimum-torque motion planning method. This new method is based on the use of optimal control theory within a recursive dynamics framework. Our dynamic motion planning methodology achieves high efficiency regardless of the figure topology. As opposed to a Lagrangian formulation, it obviates the need for the reformulation of the dynamic equations for different structured articulated figures. We use a quasi-Newton method based nonlinear programming technique to solve our minimum torque-based human motion planning problem. This method achieves superlinear convergence. We use the screw theoretical method to compute analytically the necessary gradient of the motion and force. This provides a better conditioned optimization computation and allows the robust and efficient implementation of our method. Cubic spline functions have been used to make the search space for an optimal solution finite. We demonstrate the efficacy of our proposed method based on a variety of human motion tasks involving open and closed loop kinematic chains. Our models are built using parameters chosen from an anthropomorphic database. The results demonstrate that our approach generates natural looking and physically correct human motions.

Internal EGR Systems for NOx Emission Reduction in Heavy-Duty Diesel Engines

2004 ◽  
Author(s):  
John Schwoerer ◽  
Sotir Dodi ◽  
Marty Fox ◽  
Shengqiang Huang ◽  
Zhou Yang
Keyword(s):  
Diesel Engines ◽  
Emission Reduction ◽  
Nox Emission ◽  
Heavy Duty ◽  
Heavy Duty Diesel

Comparing Cetane Number Measurement Methods

2020 ◽  
Author(s):  
Riley C. Abel ◽  
Jon Luecke ◽  
Matthew A. Ratcliff ◽  
Bradley T. Zigler
Keyword(s):  
High Pressure ◽  
Diesel Engines ◽  
Ignition Delay ◽  
High Efficiency ◽  
Performance Metrics ◽  
Fuel Injection ◽  
Cetane Number ◽  
Compression Ignition ◽  
Fuel Performance ◽  
Compression Type

Abstract Cetane number is one of the most important fuel performance metrics for mixing controlled compression-ignition “diesel” engines, quantifying a fuel’s propensity for autoignition when injected into end-of-compression-type temperature and pressure conditions. The historical default and referee method on a Cooperative Fuel Research (CFR) engine configured with indirect fuel injection and variable compression ratio is cetane number (CN) rating. A subject fuel is evaluated against primary reference fuel blends, with heptamethylnonane defining a low-reactivity endpoint of CN = 15 and hexadecane defining a high-reactivity endpoint of CN = 100. While the CN scale covers the range from zero (0) to 100, typical testing is in the range of 30 to 65 CN. Alternatively, several constant-volume combustion chamber (CVCC)-based cetane rating devices have been developed to rate fuels with an equivalent derived cetane number (DCN) or indicated cetane number (ICN). These devices measure ignition delay for fuel injected into a fixed volume of high-temperature and high-pressure air to simulate end-of-compression-type conditions. In this study, a range of novel fuel compounds are evaluated across three CVCC methods: the Ignition Quality Tester (IQT), Fuel Ignition Tester (FIT), and Advanced Fuel Ignition Delay Analyzer (AFIDA). Resulting DCNs and ICNs are compared for fuels within the normal diesel fuel range of reactivity, as well as very high (∼100) and very low DCNs/ICNs (∼5). Distinct differences between results from various devices are discussed. This is important to consider because some new, high-efficiency advanced compression-ignition (CI) engine combustion strategies operate with more kinetically controlled distributed combustion as opposed to mixing controlled diffusion flames. These advanced combustion strategies may benefit from new fuel chemistries, but current rating methods of CN, DCN, and ICN may not fully describe their performance. In addition, recent evidence suggests ignition delay in modern on-road diesel engines with high-pressure common rail fuel injection systems may no longer directly correlate to traditional CN fuel ratings. Simulated end-of-compression conditions are compared for CN, DCN, and ICN and discussed in the context of modern diesel engines to provide additional insight. Results highlight the potential need for revised and/or multiple fuel test conditions to measure fuel performance for advanced CI strategies.

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