Recently, the 5th Dassault Systèmes China DYMOLA User Day was unfolded successfully in the beautiful city of Wuxi, the Pearl of Taihu Lake. At the DYMOLA USER DAY, which returned after two years, senior experts from various fields gathered together to discuss the latest technology and innovative development in the engineering field.

First of all, Mr. Yu Naiquan @NY, CHINA Customer Process Experience CATIA Sales Senior Manager of Dassault Systèmes, made a welcome speech to kick off the conference. Mr. Yu provided a detailed overview of the developmental journey of Dassault Systèmes (Hereafter referred to as "DS"), shedding light on the company's history and milestones. He also expressed his sincere welcome to the experts and colleagues attending the conference, furthermore, he encouraged attendees to actively participate in and join the CATIA User and CATIA MBSE Communities, fostering collaboration and knowledge-sharing within the community.

Ms. Zhang Jing @JZ, DS China Systems Engineering Industry Consultant, shared with the guests the DYMOLA technology updates and development strategy, and made a detailed introduction and demonstration of the technology update of DYMOLA software itself, including model development, solvers, interfaces, model libraries and other aspects. In addition, the integration of DYMOLA with 3DEXPERIENCE platform and the overall solution of integration with SCANeR, a scene simulation software, and Scilab, a control development software, are introduced. Finally, based on the current development trend of AI, DYMOLA made technical exploration in multi-physics field simulation based on reinforcement learning, and demonstrated the design case of electric airplane autopilot controller based on artificial intelligence.

Qi Yang, Associate Professor of School of Automation, Northwestern Polytechnical University, shared the practical experience of cooperation between NPU and DS DYMOLA Innovation Center, and introduced its application scenarios in aviation electrics. NPU and DS DYMOLA Innovation Center have adopted the idea of hierarchical modeling based on the multi-disciplinary and strongly coupled characteristics of the aircraft power supply system and based on the simulation modeling needs of different design stages to establish a unified modeling and simulation specification standard,, and built the aircraft multi-electric system and electrical system simulation model libraries. Based on DYMOLA's multi-domain physical system joint simulation platform, integrated simulation verification and hardware-in-the-loop ground verification tests were carried out.

Dr. Han CHEN, Director of Carbon Neutral Digital Technology Research Office of Urban Construction of CSADI, started from the current situation and emission reduction paths of carbon emissions in the construction field, and shared the digital exploration done by Zhongnan Architectural Design Institute in the field of dual-carbon in buildings using DS 3DEXPERIENCE platform. Based on MBSE methodology, Zhongnan Architecture Design Institute built a multi-connected room cooling system model using the HVAC system as an example, and combined the advantages of Modelica in 1D system modeling with the advantages of CFD in 3D simulation to further carry out refined indoor energy consumption and environment management. Based on DYMOLA, we have conducted technical exploration of hardware-in-the-loop testing in the building field.

Based on DYMOLA's many years of application experience in Carrier Air Conditioning, Carrier Air Conditioning Engineering Manager Gao Yunhai is committed to accelerating research and development and quality improvement in the refrigeration field. Manager Gao elaborated on the application of DYMOLA in air conditioning system development through Carrier's practice in four case studies: truck refrigeration equipment, supermarket refrigeration system, residential HVAC system and general building air conditioning system. Based on the background of carbon neutrality, the new energy power system presents the characteristics of multivariate, strong coupling and nonlinearity.

Dr. Sun Li, doctoral supervisor at the School of Energy and Environment of Southeast University, emphasized that the complicated physical parameters of various types of work materials, the variable gas components, and the interlaced heat and energy storage links have brought great challenges to the dynamic simulation and control design of the system. Dr. Sun shared the experience of Southeast University in establishing the full mechanism dynamic model of fuel cell, lithium bromide absorption refrigeration and large-scale thermal power unit based on DYMOLA, and conducting joint simulation with MATLAB/SIMULINK platform through FMI protocol, debugging the advanced algorithms related to PID, self-imposed interference control and model predictive control, which can improve the operation of the complex energy power system significantly. The operation level of complex energy power system is significantly improved.

Ms. Lu Yiming, Supervisory Simulation Engineer of CRRC Tangshan Co., Ltd. introduced the simulation and application of rolling stock doors based on the development and current situation of the railroad industry and explored the digital twin way of the railroad industry. Based on DS 3DEXPERIENCE platform, Tang Che has conducted technical exploration of virtual train. At virtual train performance level , with Moldelica modeling as the core, DYMOLA was applied to carry out multi-system professional simulation and analysis, and the integrated verification of sub-systems was realized. Taking the doors as an example, Tang Che did the best practice exploration of the minimum system based on MBSE.

As an experienced VAR of DYMOLA applications, Dr. Aiguo Xu, CEO of Nanjing Yuansi Simtek Co., Ltd. demonstrated Simtek's applications in complex electromechanical and digital energy fields. With many years of Modelica modeling and simulation experience and a professional background in multiple physical fields such as electricity, thermal fluid, control, etc., Dr. Xu's team combines the model libraries of wind power, thermal power, hydropower, photovoltaic power generation, and integrated energy sources to assist customers in building distributed energy (wind power, thermal power, hydropower, nuclear power, photovoltaic power generation, etc.) networks. Dr. Xu's team help clients build distributed energy networks (wind power, thermal power, hydropower, nuclear power, photovoltaic power, etc.) to achieve two-way transmission and effective utilization of multiple clean energy sources within the power grid, and ultimately realize the optimal allocation of multiple energy sources.

Dr. Wang Bo, Technical Director of System Simulation of Beijing Hysim Technology firstly introduced the history of DYMOLA and Modelica, and narrated the development course of DYMOLA, which made the audience in the conference hall have a clearer understanding of DYMOLA. He also gave an in-depth explanation of DYMOLA's thermal management in automotive triboelectric systems. On the premise of the importance and necessity of thermal management in new energy vehicles, Dr. Wang gave a detailed introduction to the automotive triboelectric system and put forward the new demands of the automotive triboelectric system, such as the enhancement of the intelligent thermal management technology and so on. Based on the new requirements, Dr. Wang introduced DYMOLA's thermal design and thermal management solutions for automotive triboelectrics, and DYMOLA has several commercial libraries to realize the comprehensive coverage of thermal management for automotive vehicles.

At the end of the meeting, The MC - Mr. Chen Xiaozhong @XC, CHINA Customer Solution Experience CATIA Sales Expert Manager of DS, made a closing speech for the user conference. In his speech, Chen Xiaozhong expressed his thanks to the guests for their presence and looked forward to further cooperation with China DYMOLA users.

In this late autumn, on the shore of Taihu Lake, the beauty of Wuxi and the academic exchanges of the participants complemented each other. A high-level, in-depth exchange of seminar, experts and scholars in this meeting to obtain a wealth of academic information, we believe we will work together for the future development of engineering and technology to contribute wisdom and strength.

Big thanks to @GG @HF @GS for your great support in making this event a success.

Big thanks to @JZ for your support in shaping this report!