Molly Ayala
Electric wind, also known as ionic wind, corona wind, or ion wind, is a phenomenon where airflow is created by the movement of charged particles induced by electrostatic forces linked to corona discharge. This occurs at the tips of sharp conductors, such as points or blades, subjected to high voltage relative to the ground. Electric wind is an electrohydrodynamic phenomenon, and the term was first used by Francis Hauksbee in 1709.
Explore related products
What You'll Learn
- Electric wind is an electrohydrodynamic phenomenon
- It is the airflow of charged particles induced by electrostatic forces linked to corona discharge
- Electric wind is generated by charges on a sharp conductive point
- The electric field strength must exceed the corona discharge inception voltage (CIV) gradient
- A faint purple jet of plasma is visible in the dark on the conductive tip
Electric wind is an electrohydrodynamic phenomenon
Electric wind, also known as ion wind, corona wind, or ionic wind, is a phenomenon that occurs when charged particles are induced by electrostatic forces linked to corona discharge. This discharge arises at the tips of sharp conductors, such as points or blades, when subjected to high voltage relative to the ground. The resulting airflow of charged particles is known as electric wind.
Electric wind is an electrohydrodynamic (EHD) phenomenon. EHD is a joint domain of electrodynamics and fluid dynamics that focuses on fluid motion induced by electric fields. It involves the application of an electric field to a fluid medium, resulting in fluid flow, form, or property manipulation. The underlying physics of EHD-based technologies involves the generation and movement of charge carriers (ions) within the fluid.
The phenomenon of electric wind was first observed by B. Wilson in 1750, who demonstrated the recoil force associated with corona discharge. However, the term "ionic wind" is considered a misnomer due to the misconception that only positive and negative ions played a significant role in the phenomenon. A 2018 study revealed that electrons have a larger role than negative ions during the negative voltage period. As a result, the term "electric wind" is now preferred to more accurately describe the phenomenon.
In recent years, electric wind has gained attention for its potential applications. For example, in 2018, researchers from MIT successfully flew the first prototype plane propelled by ionic wind, showcasing the potential for electric wind in aviation. Additionally, electric wind has been explored for its use in energy generation, with vaneless ion wind generators using ambient wind to move ions and produce electrical energy.
Electricity Importing: Powering Nations Through Global Energy Trade
You may want to see also
Explore related products
It is the airflow of charged particles induced by electrostatic forces linked to corona discharge
Electric wind, also known as ion wind, ionic wind, or corona wind, is a phenomenon that occurs when there is a movement of charged particles due to electrostatic forces linked to corona discharge. This discharge happens at the tips of sharp conductors, like points or blades, when they are subjected to high voltage relative to the ground.
The term "electric wind" is considered more accurate than "ionic wind" because, while it was previously believed that only positive and negative ions were involved, a 2018 study found that electrons play a larger role than negative ions.
Corona discharge is an electrical discharge that occurs when the fluid surrounding a conductor becomes ionized, creating a region of plasma around the conductor. This usually occurs in the air, which is a neutral fluid, and results in the creation of a glow of blue or purple light. The phenomenon is called a 'corona' because the plasma creates a lighting crown around the electrodes.
Corona discharge typically occurs at highly curved regions on electrodes, such as sharp corners, projecting points, edges of metal surfaces, or small-diameter wires. This is because the high curvature results in a high potential gradient, causing the air to break down and form plasma. The discharge can be suppressed by improved insulation, using smooth, large-diameter rounded shapes, and adding corona rings to insulators of high-voltage transmission lines.
The corona effect is not desired on power lines as it causes power loss and interference with radio and television signals. It also creates unpleasant crackles and vibrations that reduce the lifetime of power lines.
Understanding VA in Electrical Terms: What Does It Mean?
You may want to see also
Explore related products
Electric wind is generated by charges on a sharp conductive point
Electric wind, also known as ion wind, ionic wind, or corona wind, is an intriguing phenomenon that occurs due to the presence of charges on sharp conductive points. This phenomenon is not to be confused with wind power, which involves harnessing the kinetic energy of natural wind flows for electricity generation through wind turbines.
Now, let's delve into the details of how electric wind is generated by charges on sharp conductive points:
Electric wind is the airflow of charged particles induced by electrostatic forces linked to corona discharge. This discharge occurs at the tips of sharp conductors, such as points or blades, when they are subjected to high voltage relative to the ground. The electric field generated by charges concentrated on a sharp conductive point is significantly stronger than the field produced by the same charge on a large, smooth, spherical conductive shell. This concentration of charges on sharp edges is described by the principles of electrostatics, where charges tend to accumulate more in areas with higher curvature, resulting in a stronger electric field.
When the electric field strength surpasses the corona discharge inception voltage (CIV) gradient, it leads to the ionization of air molecules surrounding the tip. This ionization results in the creation of a faint purple jet of plasma, visible in the dark, and a cloud of like-charged ions. The tip then repels this ion cloud, causing it to expand due to the mutual repulsion between the ions. This repulsion creates an electric "wind" emanating from the tip, often accompanied by a hissing sound resulting from the change in air pressure.
The phenomenon of electric wind has been harnessed in innovative technologies, such as the MIT ionic wind plane, which was the first solid-state plane propelled by ionic wind. This application demonstrates the potential of electric wind for propulsion and provides a glimpse into the future of aircraft design and efficiency.
In summary, electric wind is generated by charges on sharp conductive points through a complex interplay of electrostatic forces, ionization, and the repulsion of like-charged ions, resulting in a unique form of electric "wind" with potential practical applications.
Understanding PF: Electrical Power Factor Explained
You may want to see also
Explore related products
The electric field strength must exceed the corona discharge inception voltage (CIV) gradient
Electric wind, also known as ion wind, ionic wind, or corona wind, is an electrohydrodynamic phenomenon. It is the airflow of charged particles induced by electrostatic forces linked to corona discharge. Corona discharge is an electrical discharge caused by the ionization of a fluid, such as air, surrounding a conductor carrying a high voltage. This occurs when the strength of the electric field (or potential gradient) around a conductor exceeds the dielectric strength of the fluid, in this case, air.
The CIV gradient refers to the critical value of the electric field strength at which corona discharge occurs. In air at sea level pressure, this critical value is approximately 30 kV/cm, but it decreases with pressure, making corona discharge more likely at high altitudes. When the electric field strength exceeds this threshold, it ionizes the air molecules, creating a region of plasma around the conductor. This plasma is visible as a faint purple jet in the dark and is accompanied by a hissing noise due to the change in air pressure.
The ionization of air molecules results in the generation of ionized air molecules with the same polarity as the charged conductor. These like-charged ions repel each other, creating an electric "wind" emanating from the tip of the conductor. This phenomenon is utilized in ion wind generators, also known as electrohydrodynamic thrusters, which use this principle to convert electrical energy into kinetic energy and propel aircraft, as demonstrated in the MIT ionic wind plane.
Understanding Main Lug Electrical Panels: What Does It Mean?
You may want to see also
Explore related products
A faint purple jet of plasma is visible in the dark on the conductive tip
Electric wind, also known as ion wind, ionic wind, or corona wind, is an electrohydrodynamic phenomenon involving the airflow of charged particles induced by electrostatic forces linked to corona discharge. This occurs at the tips of sharp conductors, such as points or blades, when they are subjected to high voltage relative to the ground.
Now, when the electric field strength at the tip of such a conductor exceeds the corona discharge inception voltage (CIV) gradient, it leads to an interesting visual phenomenon. A faint purple jet of plasma, barely visible in the dark, forms at the conductive tip. This occurs due to the ionization of the air molecules surrounding the tip, resulting in the creation of ionized air molecules with the same polarity as the charged tip.
This phenomenon, known as St. Elmo's fire, has been observed naturally occurring from ships' masts and superstructures, as well as aircraft wings. The colour of this plasma jet is often described as blue-violet or purple, with a faint glow. The purple colour is a result of the plasma's interaction with the surrounding electromagnetic fields, specifically the electrons and charged air molecules, which are mostly nitrogen and oxygen ions.
The presence of charged particles in plasma makes it electrically conductive, and this property is utilised in various modern devices such as plasma televisions and plasma etching. Additionally, the concept of using plasma actuators to improve aerodynamics by modifying airflow has been explored, particularly in the aerospace industry.
Legs Down: Electrical Safety and You
You may want to see also
Frequently asked questions
Electric wind, also known as ion wind, ionic wind, or corona wind, is an electrohydrodynamic phenomenon. It is the airflow of charged particles induced by electrostatic forces linked to corona discharge.
Electric wind forms when air molecules near sharp conductive points are ionized, creating a charged ion cloud. The tip repels this like-charged ion cloud, which then expands due to the repulsion between the ions.
A small faint purple jet of plasma can be observed on the conductive tip in the dark. A hissing noise is also produced due to the change in air pressure at the tip.
When the electric field strength exceeds the corona discharge inception voltage (CIV) gradient, it leads to the ionization of air molecules near the conductive tip, initiating the formation of electric wind.
Electric wind can be generated using sharp conductive points or blades subjected to high voltage relative to the ground. This technique has been applied in the development of the MIT ionic wind plane, which was first flown in 2018.
