Pre-ignition chamber spark plugs for fast, consistent ignition of thin-burning natural gas engines

Woodward’s Fast Turbulent Ignition (FTI) provides fast, consistent ignition of gaseous fuel mixtures in internal combustion engines.

It results in more uniform and complete fuel combustion, increased engine efficiency and improved exhaust emissions.

The FTI is designed to optimise the operation of high-performance, high BMEP, lean-burn natural gas engines used in stationary power applications.

Features and Functions

Large bore engines using dilute gas fuel mixtures typically experience slower fuel burn rates and incomplete combustion.

These conditions reduce combustion efficiency and result in problematic exhaust emissions.

Typical J-gap spark plugs attempt to address these performance issues by increasing spark energy, which can shorten spark plug life.

To counteract the shortened spark plug life, J-gap manufacturers often increase the electrode area, which can have a detrimental effect on the ignition spark.

This has a “quenching” effect on the ignition spark, which increases combustion variability;

Or they use precious metals, which increase manufacturing complexity and reduce plug durability.

FTI’s unique, patented design provides consistent ignition without the need for a high-energy ignition system, reducing the need for precious metal electrodes for long life.

It can also be customised to meet specific engine combustion requirements.

FTI Advantages.

Fast, consistent fuel combustion

Improved engine efficiency

Reduced exhaust emissions

No hot running and good detonation margins

Longer life

Customisable design

Objectives achieved: Improved engine efficiencyContinuous fuel ignition – More complete fuel combustionFaster combustion – Just in Time Departure Point (ATDC) for improved combustion efficiencyImproved combustion stability

j-gap with FIT.

FTI’s patented pre-combustion chamber combustion technology www.abb-drive.com improves combustion start-up with J-gap and conventional pre-combustion chamber spark plugs.

J-gap1 Typical J-gap spark plugs have a spherical flame front that burns slowly as it passes through the combustion chamber. This type of flame front is susceptible to high turbulence in the combustion chamber, which can quench or even blow out the spark, again increasing ignition variability. In addition, smaller spark surfaces corrode more quickly, shortening the life of the spark plug.

FTI addresses these issues by using a separate flame core for ignition. The multi-jet flame front from the FTI igniter creates its own combustion chamber turbulence. This self-generated turbulence adds to existing chamber turbulence while being highly resistant to other chamber turbulence that promotes rapid flame growth throughout the fuel mixture.

Extremely poor operating conditions

Higher combustion efficiency and NOx optimised ignition timing

Reduced emissions

Reduced nitrogen oxides – ability to operate at increased λ (air-fuel ratio)

Reduced misfires – unburnt hydrocarbons

Longer life

Exceeds engine service intervals – reduces engine downtime

Multiple products – different levels of life expectancy

Zero failure rate

Reliable and robust – designed for high cylinder pressures