Reducing iterations for developing a new hydrogen valve

OMB Saleri S.p.A. (OMB) began developing small metal parts and valves for residential gas and water applications in 1980. The experience acquired in the fields of gas safety and high-pressure applications has allowed the company to expand its production range to other market segments such as automotive, aerospace modules or defense projects. In the gas safety segment, they work on vessels for gas storage and material handling.

For more than 30 years, first with compressed natural gas (CNG) and then with hydrogen (H2) components, OMB has established itself as one of the most advanced and innovative original equipment manufacturers (OEMs) in the world.

With its many possible applications across industries, H2 is rapidly gaining attention around the world. When used, it does not emit carbon dioxide (CO2). Therefore, hydrogen outputs a low amount of air pollution. This offers a solution to decarbonize industrial processes and economic sectors where reducing carbon emissions is both urgent and hard to achieve. H2 is a key priority for Europe’s clean energy transition.

In this context, the automotive fuel cell market has been proliferating by using H2 over conventional fuels like oil and gas. Companies like OMB have been developing new technologies to answer this need and provide reliable components.

OMB has a complete range of products that can take care of H2 flow path from the filling station to the high-pressure tanks, to the pressure regulator and finally to the fuel cell. Its valves are commonly used on light vehicles and trucks. The objective of OMB is to provide reliable valves that can withstand over 700 bars used for the H2 storage.

The OMB low pressure team is led by Fatima Patricia Amores, project manager and engineer of materials. Marco Bosio, product engineer at OMB, has been working to develop valves used in the hydrogen, low pressure side of a fuel cell. The company’s knowledge on the anode side of the fuel cell allows them to help their customers build up the cathode side too. Therefore, they can also provide valves for the cathode side of a fuel cell stack pack.

OMB is willing to face the challenging projects and they are accustomed to developing valves from scratch. Most of their products are innovative solutions that are filling a gap in the automotive market. Therefore, they need a reliable software to help them understand how a design modification can improve the functionality of a valve and ensure the design meets their customers’ expectations.

The simulation must address challenges such as, the dynamic response of a proportional valve, the flow rate calibration in an anode drain valve and the prediction of the on-tank valve behavior in the worst tolerance condition.

OMB used Simcenter™ Amesim™ software for its first simulation. Simcenter Amesim is part of the Siemens Xcelerator business platform of software, hardware and services. Concentrating on the pressure control valve, they simulated the mechanical deformation of the sealing pad, the flow rate and the magnetic force. The simulation was performed in a stationary condition to better understand how the specific design would impact the valve. Based on this first study, they created a Simcenter Amesim model to simulate the valve and evaluate the time needed to face a pressure variation.

They studied how a different coil control strategy would affect the pressure control and how well the outlet pressure can be regulated.

A test plan has been discussed and agreed upon to make a correlation between the outputs predicted by Simcenter Amesim and those coming from the valve. “As we speak, the design has been validated and the valves are under production”, says Bosio.

When designing a component of a complex system, it is not always possible to rely on tests and 3D simulations. Therefore, a system simulation becomes essential for those who need to quickly produce the dynamic evolution of a system.

In this case, using Simcenter Amesim helped reduce the design iterations and avoid time-consuming testing.

“We can say that with Simcenter Amesim, we save the time of an iteration in the prototypal phase. This means that, on an average, we can save six weeks on a project,” Bosio says.

“Now, when a new product is developed, we forecast at least one simulation to verify the validity of the new design. For the valves involved in safety applications, we usually simulate some failure modes too.” According to Bosio, three main elements contributed to OMB’s success using the simulation tool.

First, Simcenter Amesim is a software used in major companies. In addition, the graphical user interface (UI) is intuitive and it contains detailed descriptions of the elements.

Amores explains: “It is a widespread software in major companies, so it is possible to collaborate effectively, create networks and integrate your module into a larger system. In addition, it has intuitive graphics and a fast learning curve.” Renato Santulli, technical director at OMB, adds: “Each simulated element is accompanied by a detailed explanation, with clear references to theory and academic literature. Furthermore, the equations underlying each element are clearly laid out in C language, to satisfy anyone interested in a more precise understanding of what they are simulating.”

Without simulation, OMB would need more disruptive or time-consuming test sequences. In case of failure, the design would need a review, with an impact on the project milestones. Bosio states: “Simcenter Amesim is really helping us develop new products in no time. Before the simulation, it would have taken us several years to complete a valve”.

They also received the help of a valuable partner, BSim, which trained them to use Simcenter Amesim efficiently and helped them investigate new libraries to find the most suitable solution for their specific use.

“It is a reliable software that is being continuously developed with an excellent support team. Receiving quick and precise answers when developing a new product is extremely important, which is why OMB appreciates the collaboration between Siemens and BSim.” Bosio concludes.

OMB and BSim are now investigating how to simulate the anode water separator, where a mixture of water (H2O), H2 and nitrogen (N2) comes to a volume, condensates, and then recirculates. In this case, they are expecting Simcenter Amesim to be a good partner to work with H2.

Nowadays, the economy rewards innovative products with high technological values. So, OMB is willing to cooperate with companies from all over the world to create a strong value chain for the H2 market and reach automotive quality standards.

The simulations make it possible to design products that adhere to customer requests and are closer to market expectations. Furthermore, the predictive nature of the simulations has an impact on how the development process is conceived: different designs can be compared without waiting for long tests and this allows for an increase of the company’s know-how.

OMB’s motto – At the forefront of innovation – is a great way to demonstrate the company’s attitude to proactively welcome technological innovations. OMB positions itself as an accelerator of ideas: the experience of older collaborators blends with the innovations brought by young engineers. Thus, the knowledge gained through years of work experience is optimized by those who face engineering challenges with a new perspective.

In the future, the company wishes to rely on the intrinsic technological content of their “Millennial” engineers. The objective is to continuously improve its products to make them ever more innovative.