Touch Sensity develops SHM tool for hydrogen tanks

Source (All Images) | Touch Sensity

Touch Sensity (Nouvelle-Aquitaine, France) offers expertise in the field of intelligent materials. It develops solutions like SensityTech — a non-intrusive, nondestructive sensing system — that monitors all mechanical and thermomechanical stresses applied on a part, either due to part fatigue and exploitation or due to external event (like impacts and scratches).

Collaborating with manufacturers and OEMs in aerospace, space, defense, railway and naval industries, Touch Sensity recently announced a technology solution that targets the structural health monitoring (SHM) challenges of hydrogen pressure vessels (mainly Type 3 and 4), enabling real-time monitoring (damages and bending detection and localization) and ensuring safety, durability and predictive maintenance.

According to the company, current SHM technologies used are limited to static and local sensors that are sometimes complex to implement. Therefore, Touch Sensity offers an integrated monitoring solution covering data acquisition, processing and analysis. It is an embedded module system connected only to the periphery of the hydrogen pressure vessel via connectors (see image below). The module sends a signal into the material so as to analyze its mechanical property variations.

The monitoring tool thus provides an entire overview of the internal state of the material to prevent wear. The non-intrusive tool can be applied to materials that are solid, flexible and with environmental constraints, which includes fiber-reinforced composite and metal tanks. Touch Sensity refers to key applications in which it would be useful in such cases below:

It can monitor stationary hydrogen tanks to prevent potential leakages during their refueling and exploitation. High-pressure tanks are subject to fatigue due to multiple filling and emptying cycles, introducing microcracks and microleakages into their structure. SensityTech detects and locates real-time material properties’ variations, providing fast and reliable information on tanks integrity and before critical damages occur.

SensityTech can also be used to monitor the coating integrity of trailer hydrogen tanks, avoiding tanks dismantling and optimizing downtime. These tanks are often fitted with an internal anti-diffusion coating to prevent hydrogen infiltration, and wear on this coating can compromise safety. SensityTech detects variations in material properties associated with the internal coating degradation, identifying areas where cracks or erosion begins.

SensityTech provides operators with information on tank integrity, as well as their remaining lifetime for potential reuse in new vehicles. Tanks installed into FCEVs (trucks, commercial vehicles, taxis, trains, ferries) are subject to external events such as vibrations, chocks, scratches, temperature and to fatigue during the refueling, successively causing their degradation. Therefore, it is important to make a fast scan of the tank and locate any mechanical damages to it.

SensityTech is also useful for metal tanks. In aerospace, for instance, hydrogen can diffuse into certain metals, causing embrittlement and increasing the likelihood of cracks and sudden failure. Touch Sensity’s solution is capable of detecting changes in the properties of affected materials, identifying at-risk areas before visible cracks appear and avoiding sudden ruptures.