A bladeless fan uses the Coanda effect and Bernoulli’s principle of fluid dynamics to generate wind without wings. This innovative product, which is both safe and efficient thanks to its mechanical design, is the result of the application of the principles of fluid dynamics in various fields.
Mechanical engineering and a fan without blades
The first appliance that comes to mind during the summer months is the electric fan. Not only are they cheaper than air conditioners, but they also save money on electricity, so you don’t have to worry about running them all day. As a result, sales of electric fans skyrocket during the summer months, and a new product called a “bladeless fan” has become very popular in the seasonal appliance market this year since it was first introduced in 2009. This is exactly what it sounds like: a new type of fan that, unlike traditional fans with blades, produces air between slim, circular rings. The main advantage of a bladeless fan is that it’s much safer, as you don’t have to worry about hurting your hands on the blades. If they don’t have blades, how on earth can they create wind?
The truth is, it’s not that the blades are missing, but that the blades that create the wind are hidden inside the bottom of the fan, along with the motor. To break it down, the fan and electric motor at the bottom of the fan work to draw outside air into the machine and send it upwards. This air rises above the outlet and spins along the surface of the circular ring, and as it is expelled forward, it pulls air behind the fan, creating a large amount of wind. This process utilizes principles of hydrodynamics such as the Coanda effect and Bernoulli’s principle.
The Coanda effect is the tendency of a fluid to adsorb to a surface when it flows over a gently curved surface. For example, if you’re working out hard and sweating profusely, you might notice that the sweat that runs down your head or forehead tends to trickle down your jawline or neckline instead of dripping directly to the ground. Another example is when water from a faucet runs along the surface of a spoon. This effect causes air traveling along the surface of the circular ring at the head of an electric fan to flow rapidly along the inner surface of the ring.
Bernoulli’s principle states that the faster a fluid moves, the lower its pressure, and the slower it moves, the higher its pressure. Think of a car traveling fast on an unobstructed road versus a traffic jam. If there’s an empty road next to it, the cars stuck in traffic will want to go there. Similarly, fluids will try to move toward the faster side of the road because the pressure is greater on the slower side. Applying this principle to a fan without a blade, a flow of fast air is created through a small gap at the end of the circular ring at the head of the fan, which lowers the pressure of the air, causing the air behind the fan, which has higher pressure, to move forward. In this process, 15 times more air is moved than is sucked in from the bottom of the fan, creating the wind.
There’s a scientific principle behind the bladeless fan that has to do with the properties of fluids. The way a regular fan produces wind is also based on the principles of fluid dynamics. In fact, the principles of fluid dynamics are applied in many different ways around us. It’s not just fans, it’s airflow in the wings and engines of airplanes, how salt flakes float on water, and more. Depending on where and how these principles are applied, they can be groundbreaking ideas or just ordinary technology. So who are the people who understand the properties of these fluids and apply innovative ideas in real life? Mechanical engineering students. The Department of Mechanical and Aerospace Engineering is constantly working to study the properties of fluids and apply them to real life in a more convenient and advanced way.
Applications of fluid dynamics and the scalability of fanless fans
The principles of fluid dynamics used in the bladeless fan have applications in many different industries. For example, Bernoulli’s principle plays an important role in controlling airflow in aircraft. Aircraft wings regulate airflow properly to ensure stability during flight, which is also true in the automotive industry. The aerodynamic design of automobiles is a key technology used to improve fuel efficiency and increase stability while driving. These improvements in aerodynamic design can also be applied to improve the performance of household appliances, such as fanless fans. Further advances in this principle could even maximize the efficiency of bladeless fans or lead to new types of appliances.
The future of mechanical engineering and its continued development
Mechanical engineering continues to evolve today, fusing with a variety of advanced technologies to create new products and ideas. For example, smart devices combined with artificial intelligence (AI) are maximizing user convenience, and the Internet of Things (IoT) is playing an important role in maximizing the efficiency of mechanical devices. Household appliances such as bladeless fans can expect to continue to improve with these technological advances, and research into green energy utilization is ongoing. Mechanical engineering will continue to drive sustainable development in the future by developing environmentally friendly and energy-efficient technologies.
