Editor's Note:

Faced with the rigorous seismic, impact, and lifting-verification requirements for nuclear power safety-class cabinets, how many sleepless nights could simulation engineers and structural designers save if every design change no longer meant starting from scratch and enduring a three-week wait?

This issue's "Simulation Stories Around Me" column features the intelligent mechanical simulation platform for nuclear power cabinets, developed by Zhirui Jiang's team at Beijing Guangli Nuclear System Engineering Co., Ltd. Let's step into this case study together and see how digital-intelligent simulation is breaking down the barriers between design and simulation roles, significantly lowering the threshold for simulation, and injecting digital confidence into the independent, self-controlled development of high-end nuclear power equipment.

Abstract

The traditional full-process mechanical simulation of nuclear power safety-class cabinets relies entirely on manual operation, suffering from pain points such as cumbersome modeling and long iteration cycles that constrain the R&D efficiency of nuclear power instrumentation and control equipment. Our story recounts the team's effort to build a four-layer architecture for an intelligent mechanical simulation platform for nuclear power cabinets. Relying on secondary software development and intelligent algorithms, the platform achieves full-process automation, compressing the complete simulation cycle for a single cabinet from three weeks to five days — an overall efficiency improvement of over 60% — providing a practical reference for the independent, self-controlled digital development of high-end nuclear power equipment. Going forward, the platform will further integrate AI algorithms to achieve automatic structural optimization, continuing to empower the digital transformation of the manufacturing industry.

Keywords
Nuclear power instrumentation and control; Cabinet mechanical simulation; Digital-intelligent platform; ANSYS secondary development; Seismic verification

I. First Encounter with Simulation: Long Nights Buried in Manual Spreadsheets

My connection with nuclear power simulation began in 2009, my first year after joining Guangli Nuclear's structural team. At the time, I was responsible for the mechanical verification of safety-class cabinets for the Hongyanhe nuclear power units. Nuclear power instrumentation and control cabinets serve as the "nerve center" of a plant's operation, directly handling critical functions such as reactor monitoring, safety protection, and emergency shutdown. They must pass a range of rigorous nuclear-grade assessments — seismic, impact, vibration, lifting; and simulation analysis is a crucial front-end verification step before a design is finalized.

In the era before digital intelligence became widespread in the industry, the entire mechanical simulation process for a cabinet relied entirely on manual operation. After receiving the 3D model, the panels and shells first had to be manually cleaned of thousands of small holes, fillets, and other invalid geometric features; bolt and weld connections had to be modeled one by one as beam elements; load conditions for seismic and lifting scenarios, along with response spectrum parameters, all had to be entered by hand; and mesh generation, solution submission, stress extraction, code comparison, and report writing were all done manually. The full simulation cycle for a single standard cabinet took a full three weeks, and even a minor model change meant all the pre-processing work had to start over from scratch.

I still remember countless nights of overtime: structural designers busy optimizing their designs, simulation engineers adjusting models in step with them, repeatedly cross-checking dozens of pages of stress data against the GB50267 Code for Seismic Design of Nuclear Power Plants to determine compliance. Even new hires who had systematically studied the full theoretical curriculum — elasticity, plasticity, vibration mechanics — could not independently complete a full simulation analysis meeting nuclear-grade standards without at least two years of hands-on field experience. Design and simulation teams frequently had to coordinate repeatedly over scheduling, and heavy reliance on manual experience, distorted model simplification, and persistently high iteration costs were the industry pain points we faced day after day. It was precisely under this purely manual, experience-heavy, slow-iterating R&D model that I built my career on the front lines of nuclear power equipment simulation, accumulating more than a decade of hands-on engineering experience — giving me a deep understanding of the bottlenecks in the traditional R&D model: a high barrier to entry for simulation, long ramp-up periods for new hires, and low design-iteration efficiency. Ordinary engineers could only passively wait for simulation results; empowering front-line nuclear power design with digitalization and intelligence seemed, at the time, an unreachable goal.

II. Breaking Through: Building an Intelligent Mechanical Simulation Platform

In early 2023, against the backdrop of rapidly advancing intelligent technology, we formed a task force with a single goal: to create an intelligent mechanical simulation solution suited to the complex assemblies of nuclear power instrumentation and control equipment — handing repetitive manual work over to software, establishing a closed digital-intelligent loop of "design–simulation–verification–optimization," lowering the barrier to using simulation tools, and putting simulation work directly in the hands of structural engineers.

The biggest challenge we faced was the extreme structural complexity of nuclear power cabinets — hundreds of parts and massive numbers of bolt and weld assemblies. Traditional parametric simulation tools were suited only to simple, standardized components and couldn't adapt to such variable cabinet structures. We broke away from conventional thinking and settled on a dual-track approach: GUI-based operation combined with API encapsulation plus rule-based intelligent algorithms. We converted engineers' years of accumulated experience in modeling, connections, and loading into standardized programmatic rules, and used various intelligent algorithms — such as spatial hashing and bounding boxes — to enable the software to intelligently recognize geometric features and automatically simplify models.

During that time, we spent our days working through cabinet design requirements, breaking them down into modules — geometry cleanup, mesh generation, intelligent bolt-and-weld connection, load-case application, and post-processing evaluation — and our nights immersed in ANSYS ACT secondary development, writing batch-processing scripts and XML parameter configuration templates, and debugging remote computing scheduling interfaces. To refine the rules for intelligent connection processing, we disassembled the bolt and weld structures of over a hundred cabinet models, embedding the simulation logic for washers, studs, and contact surfaces into our algorithm library. To align with nuclear power safety-class design codes, we entered seismic response spectra, stress limits, and assessment criteria one by one, building knowledge bases including a materials library, a load-case template library, and a report template library.

The most grueling phase was integrating and debugging the platform's four-layer architecture. At the tool layer, cross-software data transfer between Creo and ANSYS frequently broke down; at the process layer, the intelligent simplification algorithm often misidentified small structural features; and at the application layer, the one-click load-case function repeatedly failed. Our team split up to stake out each module, iterating scripts over and over, testing dozens of cabinet model versions to correct the algorithm logic. One night, working late into the small hours, the program finally achieved a fully automated workflow: after importing the cabinet's 3D model, the system automatically cleans up the geometry, batch-generates bolt and weld connections, loads seismic loads with one click, and — once the solution completes — automatically extracts stress contour maps, checks them against the applicable codes to determine compliance, and outputs a standardized seismic simulation report for the cabinet. The moment the complete report appeared on screen, the few of us stared at it in silence for a long while — work that once took three weeks could now be finished entirely in five days, an efficiency gain of over 60%.

[Image caption: Intelligent Simulation Design Platform for Nuclear Power Cabinets]

III. Everyday Transformation: Simulation Reaches Every Designer's Desk

The day the platform went live, I truly understood: simulation was never meant to be the exclusive skill of a few experts — it is quietly changing the way every one of us works.

Now, when you open the 3D software, there's a dedicated "Intelligent Mechanical Simulation" menu in the top toolbar. After brief training, an ordinary structural designer can independently launch a simulation analysis without having to wait in line for a simulation engineer. After adjusting a cabinet's panel thickness or changing the bracket layout, a designer can submit a simulation task with a single click; the computing server automatically schedules processing power in the background. Submit the task before leaving for the day, and by the next morning you have a complete stress report and optimization recommendations in hand — design iteration is no longer constrained by the simulation cycle.

Last month, in a lightweighting optimization project for a Hualong One cabinet, the design team relied on our intelligent simulation platform to iterate through three structural versions in a single week. Previously, three rounds of simulation would have taken at least two months. Using simulation data, the team precisely reduced the cabinet's weight while ensuring that seismic modal and stress metrics all met nuclear safety-class standards — genuinely achieving both lightweighting and high reliability.

The platform's built-in simulation knowledge base permanently preserves over a decade of the team's accumulated engineering experience. In the past, when a senior expert retired or transferred, years of accumulated simulation judgment experience could easily be lost. Now, all material parameters, seismic load cases, and assessment criteria are stored in the database — new hires can open the platform and directly apply established standards, greatly lowering the barrier to simulation. Now, the system automatically compares multiple codes, including RCCM, ASME, and Chinese national standards, and outputs quantified comparison tables, producing objective, consistent results that completely eliminate errors from manual judgment.

I've seen with my own eyes how simulation has transformed the way the team collaborates: where design and simulation roles once had clearly defined boundaries, designers now proactively use simulation up front to anticipate structural defects, rather than discovering seismic failures only after prototype fabrication — substantially reducing prototype rework and testing costs. Simulation is no longer a verification step tacked onto the end of a project, but a decision-making tool embedded throughout the entire design process, with every structural modification backed by virtual simulation data.

IV. Looking Ahead: Beyond Nuclear Power, the Broader World of Simulation

This intelligent mechanical simulation solution for nuclear power instrumentation and control has already been applied across the full range of nuclear-grade equipment — cabinets, panels, enclosures, and modules. It is also well suited to product development involving complex assembly structures and demanding mechanical environments, all of which can reuse this same approach of "intelligent pre-processing + standardized knowledge base + automated reporting."

Looking back on these years spent alongside simulation, my understanding has been completely transformed. I once thought of simulation as dry finite-element calculations and cold stress contour maps. Now I understand that at its core, simulation is about digitally replicating reality, using virtual testing to avoid real-world risk, and using intelligence to preserve engineering wisdom. It lives in every structural optimization decision a designer makes, in the baseline safety assurance of nuclear power equipment, and in every step of the manufacturing industry's digital transformation. It is engineering experience passed down and preserved — it is the digital confidence behind the independent, self-controlled development of domestically produced nuclear power equipment.

Going forward, we will continue to iterate on the simulation platform, incorporating more AI-based intelligent optimization algorithms to achieve automatic structural optimization and parallel computation across multiple load cases — making simulation ever lighter and more intelligent.

Author Profile

Zhirui Jiang

Born in 1980, male, holds a master's degree from Beihang University and the professional title of Senior Engineer (Professor-level). He currently serves as Deputy Chief Engineer of the Technology Center at Beijing Guangli Nuclear System Engineering Co., Ltd. With eighteen years dedicated to the R&D of digital nuclear power instrumentation and control and high-end industrial control equipment, he has received multiple provincial- and ministerial-level industry science and technology awards, holds 25 patents, and has published more than 15 articles.

E-mail: jzhirui@163.com

《万物仿真》based at the Asia Simulation Federation, focuses on simulation and industry, and features three columns. "Simulation Stories Around Me" welcomes your warmth and resonance; "Excellent Simulation Cases" looks forward to your sharing of deep exploration and practice; and "Expert Perspectives" awaits your insightful views leading the future of simulation.