May 2020

n PHARMACEUTICAL AND MEDICAL n Digital twins cut development time for respirator masks I n a 24-hour period, a typical person takes between 17,000 and 23,000 breaths – mostly without any conscious effort. As has recently become apparent, in the event of serious illness, breathing can become a struggle and the global manufacturer Vyaire Medical develops respiratory products for these situations. Not only do patients come in a variety of shapes and sizes, but they also breathe in a variety of ways. Some are “mouth breathers”; others are “nose breathers”. Most people breathe using a combination of the two. In addition, each patient has a unique breathing profile, that depends on their lung function and structure. All of these factors can be taken into account when simulating how a person breathes.. To ensure that its products are tailored as accurately as possible to the needs of individual patients, Vyaire generates precise models of actual human heads, based on scans, when developing its equipment. It also simulates the breathing process uses Siemens’ Simcenter Star-CCM+ simulation software. The use of digital twins largely eliminates the need for physical prototypes. “Traditionally we were forced to use simplified models in the development of respiratory masks,” explains Dr Christopher Varga, a senior engineering fellow and senior director of r&d at Vyaire Medical. “We would have used a simplified head model for our CFD [computational fluid dynamics] simulations, with idealised breathing holes for the nose and the mouth. “Today,” he adds, “we are using scans of actual human heads – different morphologies of actual patient features. We are starting to build a library of patient morphologies, which already consists of representative patient geometries for all of the patient populations: adult, paediatric and infant.” Varga believes that the biggest benefit of using simulation software is the time that it can save. “Early in our development cycles for a new product, we are trying to achieve feasibility goals, being able to work inside the simulation, instead of building and testing expensive physical prototypes,” he explains. “This shortens the time cycles and makes things move much faster. “We can make products much quicker and that, of course, is very important in today’s environment.” n The development of respiratory masks (above) has been accelerated by the use of simulation software and digital twins This simulation (right) shows oxygen delivery for a heavy breather using both their mouth and nose