Research Status, Key Technology and Its Application Prospect of Complex Products Assembly Quality Control and Prediction Based on Digital Twin

In order to solve the problem of unmeasurable assembly performance of complex product, the digital twin-driven assembly quality control and prediction of complex product is studied by means of cyber-physical fusion in the assembly workshop. The connotation of digital twin intelligent assembly is introduced, the current research status of complex product assembly quality is compared and analyzed, and three main key technologies for the assembly quality control of complex product are proposed: (1) multidimensional, multi-scale, multidisciplinary modeling and simulating of digital twin-driven assembly; (2) multi-source heterogeneous data collection, sensing and fusion for assembly processes; (3) data-driven decision making, feedback and optimization technology. Finally, the application of digital twin technology in the field of assembly quality control of complex product is prospected.

Unified multidisciplinary modeling and simulation analysis of internal power system

The internal combustion power equipment is a typical cyber-physical system (CPS). The traditional design method is to separate the information system from the physical system, and then to simulate and optimize separately every system. That can not achieve the best performance. Aiming at the internal combustion power equipment with multi-disciplinary deep integration, this paper establishes the multi-disciplinary model of the whole and key components based on Dymola software. There are mainly mechanical system, combustion system, cooling system, control system and other simulation models, including deceleration and fuel cut-off control unit modeling, start-stop control unit modeling and speed limit control unit modeling. The performance of each model is simulated and analyzed. The mathematical models of engine characteristic curve and fuel supply rate curve are established through experimental study. Finally, taking the simulation model of automobile power system as an example, the simulation calculation and experimental verification are carried out, and the relationship among fuel supply rate, torque, speed and valve of internal combustion engine is obtained, as well as the cooling capacity of the cooling system is studied. The experimental results show that the maximum error between the simulation speed curve and the actual speed curve is within ± 2 km/h. The research results of this paper can provide theoretical basis for multidisciplinary modeling and simulation of internal combustion power equipment, and also provide technical support for performance analysis of internal combustion engine.

Quantifying the Environmental Design Trades for a State-of-the-Art Turbofan Engine

Aircraft and engine technology have continuously evolved since their introduction and significant improvement has been made in fuel efficiency, emissions, and noise reduction. One of the major issues that the aviation industry is facing today is pollution around the airports, which has an effect both on human health and on the climate. Although noise emissions do not have a direct impact on climate, variations in departure and arrival procedures influence both CO2 and non-CO2 emissions. In addition, design choices made to curb noise might increase CO2 and vice versa. Thus, multidisciplinary modeling is required for the assessment of these interdependencies for new aircraft and flight procedures. A particular aspect that has received little attention is the quantification of the extent to which early design choices influence the trades of CO2, NOx, and noise. In this study, a single aisle thrust class turbofan engine is optimized for minimum installed SFC (Specific Fuel Consumption). The installed SFC metric includes the effect of engine nacelle drag and engine weight. Close to optimal cycles are then studied to establish how variation in engine cycle parameters trade with noise certification and LTO (Landing and Take-Off) emissions. It is demonstrated that around the optimum a relatively large variation in cycle parameters is allowed with only a modest effect on the installed SFC metric. This freedom in choosing cycle parameters allows the designer to trade noise and emissions. Around the optimal point of a state-of-the-art single aisle thrust class propulsion system, a 1.7 dB reduction in cumulative noise and a 12% reduction in EINOx could be accomplished with a 0.5% penalty in installed SFC.

Improving Student Readiness for Inquiry-Based Learning: An Engineering Case Study

<p><span lang="EN-GB">During the past decade, the authors have sought to advance student research in a predominantly teaching institution. The two primary challenges were: academic - how to introduce and promote inquiry-based learning (IBL) given the constraints, and business - how to obtain and sustain funding in the area of industry-sponsored research. The authors developed a successful multidisciplinary modeling course that integrates four teaching and learning strategies and where key learning outcomes strengthen student readiness to engage in research. The course culminates with research performed as part of an IBL strategy that is relevant and supported by mentoring. The benefits include development of intellectual and practical skills that underlie a central activity of engineering design. The course structure, evidence of student work, and evolution over time to meet challenges are presented and discussed. Most importantly, the potential of this strategy to be implemented across other topical areas is addressed. Student participation in research improves learning of engineering and scientific concepts, increases interaction with faculty and industry sponsors, and provides opportunities for work in emerging technology areas. Benefits accrue both to students who pursue a research career and to those who enter applied fields by strengthening their ability to propose innovative solutions.</span></p>