Electrostatic Spark Discharge is real and extremely common for turbine users! Static electricity at a molecular level is generated when dry oil passes through tight clearances. It is believed that the static electricity can build up to a point whereby it produces a spark. There are three stages of ESD.
1. Static Electricity builds up to produce a spark – Temperatures exceed 10,000°C and the lubricant begins to degrade significantly.
2. Free radicals form – These contribute to the polymerisation of the lubricant
3. Uncontrolled polymerisation – Varnish and sludge produced (some may remain in solution or deposit on surfaces) which can also result in elevated fluid degradation and the presence of insoluble materials.