Aircrafts on a Runway to Generate Electricity

“Boeing use noise produced by an aircraft on a runway to generate electricity. The patent mentions installing multiple acoustic collectors on both sides of a runway”

When you hear of scientific innovations at airports, they\’re usually trying to offset the environmental cost of such a necessary and long-haul mode of transportation. Airports and air travel are traditionally loud, expensive, and not too kind on the world we live in, but Boeing\’s latest idea, according to a recently filed patent, wants to give something back: it floats the idea of harvesting energy from the sound of planes taking off.

A turbo-fan aircraft taking off 200 feet away will produce noise at 118 decibels, past the human threshold for pain and damage from long-term exposure. A jet taking off just around 80 feet away can produce noise levels up to 150 decibels, which can rupture the eardrum. There’s a reason you see airport personnel on the runway wearing what are probably the biggest ear muffs available on the market.

There is one major thing to consider, however: High noise levels aren’t just bad for human health, the resulting vibrations can do a great deal of damage to surrounding structures (like roads, buildings, vehicles, etc.). Creating something that can help to significantly absorb that sound and limit the amount of force accumulated by that noise could go a long way toward preserving expensive infrastructure and objects for longer periods of time.

Enters Boeing with an idea to do something useful with all that excess acoustic energy: Turn it into power for the people!

That’s the idea behind the company’s latest patent, which outlines a “method for generating electricity from acoustic energy from an aircraft on a runway.”

How Boeing’s Acoustic Electricity Generator System Works??

 The acoustic electricity generator of Boeing consists of four parts:

  1. Acoustic wave collectors,
  2. An acoustic converter,
  3. A turbine and a generator.

An acoustic wave collector collects acoustic wave from the noise produced by aircraft on runway, and directs the collected waves to an acoustic converter.The implications are important in terms of money and logistics. Runways would receive an overhaul and their borders would be lined with \”acoustic wave collectors.\” These devices catch and collect the vibrations caused by a plane engine\’s noise. The acoustic energy is then converted into air flow, which in turn powers a turbine. A generator coupled to the turbine\’s rotating shaft generates electricity, which is sent to a substation and distributed to where it is needed.

The acoustic converter receives these waves to produces output airflow. For producing output airflow a vibrating drum is mounted within the converter assembly. The drum moves up and down when excited by the incoming acoustic waves.

As the drum vibrates, it acts as an air pump to draw the air in, and then pushes the drawn-air down to form an output air flow.

This outputted air flow is then directed to the turbine chamber where it rotates the turbine shafts. The turbine shafts, which are further coupled to the generator, in turn, make the generator to generate electricity.

Thus, the converter assembly may include an acoustic wave guide mounted within converter drum housing above vibrating drum. Acoustic wave guide is fixed within converter drum housing by couplings and is preferably conical in form, with a wider inlet at an upper-end and a narrower outlet at a lower end. Acoustic wave guide amplifies the directed acoustic waves received at the upper end. Acoustic wave guide may also include a spring having an upper end mounted at the lower end.

A lower end of spring is connected directly to vibrating drum, preferably within a recess in a top portion of vibrating drum. Spring further amplifies the received converted acoustic waves, to further increase the movement of vibrating drum and thus increase the amount of air directed downward to turn the turbine blades. Acoustic wave guide is shown with a conical form. As one of ordinary skill in the art will readily recognize, other forms may be employed. The alternative form may depend, for example, on the cross-sectional form of converter drum housing and acoustic wave guide may have an inverted pyramid form when converter drum housing has a square cross section.

The patent also mentions installing multiple acoustic wave collectors mounted on both sides of a runway. These multiple collectors will generate and direct the airflow to a single turbine chamber positioned below the converters. Such an arrangement will minimize any air flow losses between converter assembly and turbine chamber.

As with any patent, this only represents part of Boeing\’s thinking and future planning – the idea might never become practically viable or might change in scope and design along the way – but if there is a way to utilize the energy coming from the sound of your aeroplane taking off, Boeing\’s engineers are doing their best to do it.

By Sanath M V

Photo Credit: AndrewW.Sieber/ / CC BY-SA 2.0