Engineering

The Research Brief is a short take about interesting academic work. The big idea A new plant-based substitute for polyurethane foam eliminates the health risk of the material, commonly found in insulation, car seats and other types of cushioning, and it’s more environmentally sustainable, our new research shows. Polyurethane foams are all around you, anywhere a lightweight material is needed for cushioning or structural support. But they’re typically made using chemicals that are suspected carcinogens. Polyurethanes are typically produced in a very fast reaction between two chemicals made by the petrochemical industry: polyols and isocyanates. While much work has gone into finding replacements for the polyol component of polyurethane foams, the isocyanate component has largely remained, despite its consequences for human health. Bio-based foams can avoid that component. These bio-based foams avoid the need for petroleum pro...

Electric planes might seem futuristic, but they aren’t that far off, at least for short hops. Two-seater Velis Electros are already quietly buzzing around Europe, electric sea planes are being tested in British Columbia, and larger planes are coming. Air Canada announced on Sept. 15, 2022, that it would buy 30 electric-hybrid regional aircraft from Sweden’s Heart Aerospace, which expects to have its 30-seat plane in service by 2028. Analysts at the U.S. National Renewable Energy Lab note that the first hybrid electric 50- to 70-seat commuter plane could be ready not long after that. In the 2030s, they say, electric aviation could really take off. That matters for managing climate change. About 3% of global emissions come from aviation today, and with more passengers and flights expected as the population expands, aviation could be producing three to five times more carbon dioxide emissions by 2050 than it did before the COVID-19 pandemic. Aerospace engineer and assi...

Curious Kids is a series for children of all ages. If you have a question you’d like an expert to answer, send it to curiouskidsus@theconversation.com. Why do we use gasoline for small vehicles and diesel fuel for big vehicles? – Methdini, age 15, Sri Lanka Gasoline fuels most light-duty vehicles, such as passenger cars and pickup trucks. Heavy-duty vehicles, like buses, delivery trucks and long-haul tractor-trailers, typically run on diesel. Both fuel types are needed because gasoline and diesel engines have different strengths. As my automotive engineering students learn, this makes them suitable for different uses. Let’s start with what they have in common. Gas and diesel engines both work through a process called internal combustion. First, they mix fuel with air because the fuel needs oxygen from the air to burn. Next, they compress the fuel-air mixture, which ma...