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Hey everyone,

There's been a lot of questions regarding how our plugs work, so I decided to create this thread to hopefully serve to answer any questions or concerns you might have. It's pretty long, so if you just want a quick summary - I recommend watching the video :D

Section I - Introduction

I would like to begin by linking our 'How Pulstar Plugs Work' video. It features actual footage of Pulstar’s plasma-forming pulse and improved fuel burn captured by AVL, a certified testing laboratory frequently used by most major automotive manufacturers. We developed this video in order to clearly explain and highlight complex subjects such as plasma physics, energy compression, and nano-plasma combustion chemistry to the general public.

Pulstar Spark Plugs use innovative plasma-assisted combustion technology to increase horsepower, torque and improve fuel efficiency. Plasma saturated fuel ignites immediately and burns rapidly to improve engine performance.

Plasma-assisted combustion is already used to improve engine performance for racing, but requires complex control systems and costs nearly $2,000 per cylinder. Pulstar Spark Plugs, manufactured by Enerpulse Technologies, brings plasma-assisted combustion to consumers with a simple spark plug upgrade for less than $18 a cylinder. Pulstar uses a patented internal capacitor, developed with the help of a US Department of Energy laboratory, to create a high-intensity electrical pulse that ionizes the air-fuel mixture and saturates it with combustion-enhancing plasma. With its plasma-assisted combustion, Pulstar ignites fuel instantly and burns it rapidly; delivering excellent engine output and wicked throttle response.

Section II - Pulsed Power

Pulstar uses pulsed power technology to create a powerful 5MW pulse of energy upon spark formation. To form a spark, a vehicles ignition coil will slowly (relative to the process) inductively increase the voltage delivered to the spark plug until enough voltage is being delivered to allow electricity to bridge the air-fuel mixture between the center electrode and ground strap of the spark plug. This is known as achieving breakdown voltage. Pulstar Spark Plugs use a patented internal capacitor to store this energy prior to achieving breakdown voltage. When a spark is formed the energy stored in the capacitor is released in a quick and powerful pulse. This pulse is equal to 5,000,000 watts and takes approximately three nanoseconds to complete. The intense converts a portion of the gaseous air-fuel mixture into a highly excited plasma that conditions the fuel mixture to ignite immediately and burn efficiently.

Captured by AVL using a process known as Schlieren high-speed photography, this video shows Pulstar’s 5MW pulse followed by the plasma affected fuel mixture burning at an increased rate compared to a conventional spark plug.

Energy delivered by the ignition coil prior to the spark is stored in Pulstar’s capacitor and rapidly released when breakdown voltage is achieved.

Section III - Patented Capacitor

Pulstar uses a patented internal capacitor to store and compress energy prior to the spark. Pulstar’s insulator is made of engineered high-purity ceramic, forming a dense barrier between the metal shell (negative plate) and the copper silica gas seal (positive plate.) The insulator acts as a dielectric media, allowing the shell to attract energy but preventing it from crossing. This forces the energy to store on the positive plate until it can cross the spark gap, forming an intense pulse of energy.

A typical capacitor has three parts: a positive plate, a negative plate, and a dielectric media. The positive plate attracts the energy while the negative plate provides it access to ground. The dielectric media allows the negative plate to attract energy but prevents it from crossing between the two plates, forcing the energy to collect and be “stored” on the positive plate. When the energy is released, a quick and powerful pulse of energy is created; delivering a large amount of instantaneous power over a short period of time.

Dielectric Media (Insulator):
Repurposed by using high-purity, engineered, ceramic. Prevents energy from traveling between the two plates yet allows the shell to act as negative plate.

Negative Plate (Shell):
Normal metal shell. Attracts energy to ground.

Positve Plate (Gas Seal):
Copper silica gas seal. Stores energy unable to access ground.

Parallel Capacitor

The capacitor is in parallel with the high voltage circuit, meaning the energy delivered by the ignition coil sees the capacitor and the spark gap simultaneously. While the voltage is ionizing the gap, energy is flowing into the capacitor (charging the capacitor). The resistance across the gap is infinite (open circuit) while the resistance in the capacitor is less than infinite. A resistance reversal takes place when ionization occurs and the spark is formed, the resistance in the gap becomes less than the resistance in the capacitor. The gap acts as a switch, automatically triggering the capacitor. At which point whatever energy is stored in the capacitor (3-10mJ) discharges into the combustion chamber creating the plasma-forming pulse.

Section IV - Plasma-assisted Combustion

Pulstar’s intense pulse breaks apart the gaseous atoms to form highly-excited plasma. Pulstar’s 5MW pulse subjects gaseous atoms to a large amount of energy, breaking them apart to form plasma: a collection of positively and negatively charged highly reactive particles. Plasma created by this high-intensity pulse results in three major benefits in fuel combustion: instant ignition and a quicker and more complete burn.

Liquid, solid and gas are the three well known states of matter; by subjecting gas to a large amount of electrical energy the fourth state, plasma, is formed.

For instance, this diagram shows gas atoms with a positive core and orbiting negative electrons. To form plasma, these gas atoms are subjected to a large amount of energy and broken apart to form a collection of positively and negatively charged highly reactive particles. Plasma consists of positively charged ions with most or all of their detached electrons moving freely about in a very active manner; these electrons react with other atoms.

Pulstar stores energy accumulated over a relatively long period of time in its internal capacitor and releases it entirely in less than three nanoseconds. This massive dump of energy happens so quickly that the pulse it forms is equal to 5 megawatts. This 5 MW pulse interacts with the gaseous air-fuel mixture, breaking its molecules apart. This is known as ionization, the process by which an atom or molecule acquires a negative or positive charge by gaining or losing electrons to form ions. By ionizing the gaseous air-fuel mixture, Pulstar breaks down natural elements like H2 and O2 into their atomic state of H and O where they are most volatile. Thus, the portion of the air-fuel mixture affected by the pulse has been turned into plasma.

Plasma created by the high-intensity pulse of energy results in three major benefits in fuel combustion: instant ignition and a quicker and more complete burn.

Instant Ignition

Temperature Increase.The high-intensity pulse creates a flash of heat that helps the fuel charge reach the required light-off temperature to ignite the air-fuel mixture. The flash point for gasoline is about 600oF and 1,100oF for natural gas. The heat provided by the plasma, gives the air-fuel mixture a head start to achieving the temperature required to ignite.

Volatile Air-fuel Mixture. The high-intensity pulse ionizes the gaseous air-fuel mixture, breaking down air-fuel components like H2 and O2 into their atomic state of H and O where they are most volatile. These highly excited elements along with radicals react to the ensuing spark by igniting instantly.

Quicker Burn

Fuel Fragments. The high-intensity pulse breaks apart the long hydrocarbon chains found in the nearby air-fuel mixture into shorter chains that react quickly. This area of the air-fuel mixture burns faster.

Complete Burn

Fuel Fragments. The portion of the fuel that contains shortened hydrocarbon chains burns faster, and creates a larger surface area to ignite the rest of the gaseous air-fuel mixture. This allows the air-fuel mixture to burn more completely during the power stroke.

Ionic Wind. The high-intensity pulse knocks off electrons from the air-fuel mixture molecules. These ions are thrown out of orbit and knock off additional ions from neighboring molecules, creating a cascading effect. This process helps expand the formation of plasma beyond the high-intensity pulse’s immediate vicinity. As previously mentioned, this plasma field burns at an accelerated rate.

Section V - Larger Electrode

The plasma-forming pulse allows Pulstar to use a larger electrode, which extends its life. Because the plasma-forming pulse allows the fuel to ignite immediately and burn rapidly, Pulstar Spark Plugs don't need the extra nanoseconds gained by using a fine wire electrode made durable by precious metals (such as iridium or platinum). Pulstar's electrode life is extended through the use of a larger center wire made of an austenite nickel-chromium-based superalloy known as Inconel.

When the piston reaches the optimum point, the ignition coil begins to send electrical current to the spark plug to form a spark. The electrical current attempts to get to ground but cannot because it must first cross the air between the center electrode and ground electrode of the spark plug. Before the energy can cross the spark gap, it must build a bridge of ions in the air between the two electrodes. The ignition coil slowly (relative to the process) increases the voltage until a strong enough electrical field is formed to ionize the spark gap – this is known as spark jump voltage or breakdown voltage. Once the ions become concentrated enough, the energy finally flows across the spark gap, forming the spark.

For many years, spark plug makers used a large diameter electrode in an attempt to extend the life of their spark plugs. Unfortunately, larger electrodes create a larger surface area where ions can form. Spark creation timing is less consistent because the time it takes to form a condensed amount of ions in one area is random.

In an effort to increase spark creation consistency, spark plug manufactures moved to a fine center-wire plug. The smaller diameter surface area allows ions to form in a compressed area, ensuring a more consistent spark formation. As previously mentioned consistent spark creation ensures that the fuel-mixture is ignited at the optimal time; resulting in a smoother idle, quicker throttle response and improved engine performance. According to DENSO®, their fine-wire electrode plug “redefines performance driving with the worlds smallest iridium alloy electrode diameter of 0.4mm” by “[enabling] a high concentration of electrical field which requires lower jump spark voltage. This improves ignition performance, eliminates misfiring and translates into high performance driving. The lower required voltage and high ignitability from the iridium electrode also guarantees smoother idling, improved acceleration and high response driving.”

Pulstar with PlasmaCore plugs are able to take advantage of a larger electrode because our plugs have a capacitor that produces a 5,000,000 watt pulse to pre-sensitize fuel mixture for combustion and produces a spark channel 10 times larger than conventional plugs. These features allow Pulstar pulse plugs to ignite the fuel mixture instantaneously upon spark creation, and burn it more quickly. Pulstar plugs ensure precise combustion no matter the size of the electrode because we can burn more of the fuel consistently, even if it takes longer to ionize the spark gap. Additionally, our large nickel-chromium superalloy electrode extends the life of the plug by slowing electrode wear to preserve your spark gap.

The image below demonstrates how the fine wire electrode ionizes the spark gap quicker than the large diameter electrode by compressing the electrical field. Consistent spark creation is ensured because the ions are forced to form a conductive bridge between the positive and negative electrodes in a condensed area. The fine-wire flame kernel is initiated at a consistent time during each ignition cycle but is rather small in volume. The wide electrode takes longer to create a spark because the ions take longer to form the conductive bridge because of the less concentrated field. The Pulstar with PlasmaCore plug also creates the spark at various times; however the initial flame front is significantly larger and burns the fuel more quickly upon spark creation which results in more consistent and complete ignition. This is made possible by the fuel-sensitizing plasma field formed by the high energy plasma in the Pulstar PlasmaCore spark. Actual footage of Pulstar’s burn compared to a leading brands premium fine-wire iridium plug was captured by AVL, the world’s largest independent company for the development of powertrain systems with internal combustion engines.

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