What is the effect of the electrode shape of aircraft model spark plugs on the performance of aircraft models?

1. The effect of electrode shape on ignition efficiency
The pointed center electrode of aircraft model spark plugs (such as iridium material) can produce concentrated fire cores at a lower voltage, reduce ignition delay, and is suitable for the high-speed and frequent start-stop working environment of aircraft model engines. The spark energy of the pointed electrode is concentrated, which can quickly ignite the mixture and improve the success rate of cold start.
The multi-pole tip gap design of the spark plug can expand the ignition range through multi-path discharge and reduce the flame propagation blind area. This design can improve the ignition reliability and avoid product flameout under lean oil mixture conditions (such as high-altitude low-oxygen environment).

2. The connection between electrode shape and combustion efficiency
The sparks generated by the slender electrode are closer to the combustion center, shortening the flame propagation distance, making the mixture burn more fully, and reducing the emission of unburned hydrocarbons. For methanol-fueled aircraft model engines, thin electrodes can reduce the rate of carbon deposit generation. High calorific value (cold type) spark plugs need to be equipped with a short skirt electrode design to prevent the electrode from overheating and melting. Low calorific value (hot type) requires long skirt electrodes to maintain the working temperature.

3. The influence of electrode shape on the engine
Square-shaped electrodes have good initial ignition performance, but after long-term use, the edges and corners wear and become round, resulting in spark dispersion. Model aircraft engines are prone to carbon accumulation due to frequent low-speed flights, so it is necessary to choose sharp electrodes or replace them regularly to maintain performance.