Multi spark plug
- 1. “Multi-Spark Plug” is no end for innovation” Submitted by: Rishabh Jaiswal Rohit Meshram Govind Mishra
- 2. Abstract Multi spark ignition system has proved their potential in improving the performance of the engines and improved emissive characteristics as compared with the single spark plug ignition system. Recently a new type engine has been introduced which uses triple spark plugs at different location, controlled by an advanced electronic control unit. Experiments were conducted at different load conditions and different types of engines has proved that multi spark plug ignition engines are surely better than a single spark plug engine .
- 3. Measurement of Minimum Ignition Energy
- 4. Spark discharge formation in system Inductive ignition system is the most widely used. The operation of inductance ignition system is divided into two periods: Energy storing (also known as dwell angle or time) and spark discharge period. During dwell period the current in the circuit rises by exponential curve. If there is known inductance L and resistance R of the primary windings of ignition coil and voltage of the accumulator V, current i in circuit can be described by formula: t e R V i 1 R L
- 5. Estimation Ignition energy The primary coil can be modelled as a resistance and an inductance in series, with the primary current, i, defined by The energy input to the (Ep) of the primary coil is the integration of the instantaneous current (i) and the supply voltage (V) over the period the coil is switched on :
- 6. The energy stored in the coil (Es) is defined as
- 7. Heat Generation During Spark
- 8. Ignition thermal efficiency Increase of the internal energy temperature after ignition
- 9. Increase of the internal energy:
- 12. Variation of flame surface density with the number of spark plugs
- 13. Faults and wear Symptom Cause Possible consequences Spark erosion, corrosion Thermal overload Incorrect thermal value Melted electrodes Wrong or poor fuel Incandescent ignitionMisfiring (due to larger electrode gap) Incandescent ignition Residues in combustion chamber Faulty valves Plugs with incorrect thermal value Fuel with insufficient octane count Piston damage Valve damage Spark plug damage Knocking Fuel with insufficient octane count Wrong ignition Excessive compression Uncontrolled rise in pressure timing and temperature can lead to piston and spark plug damage Misfiring Faulty, old, leaking spark plug connector Spark-over to insulator; Damage of the catalytic converter
- 15. 1. CO emissions decrease with load in all three conditions because at high temperature CO gets oxidized 2. It is least for the triple spark engine.
- 16. 1.Triple spark engines have lesser and better UBHC emission due to better and faster completion of combustion. 2. UBHC emissions are higher in single spark engine because of incomplete combustion
- 17. 1. In all the cases it increases with the increase in the load. 2. Initially volumetric efficiency is maximum for single spark engine and minimum for triple spark engine.
- 18. 1. Brake thermal efficiency is maximum for triple spark mode 2. Variation increases more the increase in load
- 19. Conclusions Combustion process in triple spark engine takes place 27% faster than twin spark and 50% than single spark engine due to faster flame propagation. Brake thermal efficiency of twin spark engine is 5.1% higher and BTE of triple spark engine is about 13% higher than single spark engine The UBHC emission in triple spark engine is reduced by 29% and in twin spark engine it is reduced up to 13% as compared to the single spark engine. The CO emission in triple spark engine and twin spark engine are also reduced to a great extent. NOx emissions are increased by 3.3% in triple spark engine and 13% in twin spark engine as compared to single spark engine at full load.