Lung ventilators at UFRJ
Updated: May 7, 2021
How the knowledge generated and learned at UFRJ Nautilus can be useful in the Covid-19 crisis: Drawing a parallel with the UFRJ ventilator design
The current crisis scenario caused by the new Coronavirus has raised a great concern since the disease can generate complications in the respiratory tract, being therefore a great risk mainly for people with previous respiratory diseases. In this way, scientists and engineers from around the world bet on the idea of producing mechanical fans quickly, simply and economically, so that it can meet the growing demand for the equipment during the Covid-19 crisis. Mechanical ventilation, also called pulmonary ventilation, is the use of a machine to assist the entry and exit of air in the lungs, providing oxygen-rich air and being of frequent use in patients with respiratory failure.
Mechanical fan test prototype
As a team focused on subsea automation, UFRJ Nautilus seems to be out of the context of the current global crisis. However, if we look carefully, we will see that several essential tools for the team are equally important for projects such as the pulmonary ventilator and many other medical instruments, used in laboratories and hospitals. CAD software, 3D printing, electronics and programming, skills necessary to carry out these projects, are some of the many domains developed within the team. We followed the fan project developed by UFRJ a little more closely and it was extremely satisfying to be able to prove the importance and usefulness of the techniques and knowledge that we generate and learn both within the classroom and within the team.
One of the best known 3D CAD software is SolidWorks, the most used program for the Hydrodynamic and Mechanical development of our AUV. One of our ex-members is involved in the UFRJ fan project and, using SolidWorks, modeled a PEEP valve (Final Expiratory Positive Pressure). Three-dimensional modeling is a common and fundamental skill for the development of mechanical projects in general, whether they are underwater vehicles or mechanical fans.
Modeling of the PEEP valve Result of PEEP valve modeling
Just like the valves, tubes and the like used in ventilators, the mechanical design of an AUV also needs to take into account its positive pressure (pressure that pushes the waterproofing against the structure) and its negative pressure (pressure that acts to force the detachment of the structure), in order to remain watertight. We cannot allow water to enter its internal components or air to escape from it, so we need to use valves and seals, such as O-rings, in our project.
Another point of convergence is regarding the use of CFD simulation software (acronym in English for Computational Fluid Dynamics), used mainly in analysis and problem solving in the fields of thermodynamics and fluid mechanics. In the UFRJ initiative, OpenFOAM was used, whereas, in our team, ANSYS is used for this same function, needing the best effect of fluids in the most diverse materials and structures, whether that fluid is air, as is the case of a lung ventilator, or water, in the case of an AUV.
However, any good engineering project does not live only from simulations and other computational devices. Mechanical manufacturing concepts are necessary, as is the case with 3D printing, which allows the creation of a three-dimensional model from successive layers of material. This revolutionary technology has great advantages, such as low cost, easy to find materials and reduced production time. Thus, 3D printing is widely used, both in the design of the UFRJ Nautilus autonomous underwater vehicle, and in the production of mechanical fans of the current demand.
Therefore, we see that these projects, although different, make use of tools in common and have many similarities, both at a technical level and at a management level. Working at UFRJ Nautilus is to adapt to any possible scenario, after all, we learn here practices and skills that, technical or not, will serve us not only for academic projects or in the job market, but also for life. The knowledge generated and learned here can be useful in a scenario such as the Covid-19 crisis because we focus on technology production using tools of general use and low cost, seeking to unite different fields of knowledge. After all, in a crisis like the one we are experiencing, professionals with basic needs, in the health and science fields, must unite so that, through their work, their ideas or their inventions, it is possible to alleviate and put an end to this exhausting and tragic process that we are going through.
Written by Gabriela Torres e Ana Beatriz Ferreira