1. STUDY OF LOW VOLTAGE WATER
MIST INDUCTION CHARGING:
WATER PRESSURE EFFECT
SITI NUR’AIN BT AJIS [25109]

2. INTRODUCTION
• Water mist system is the water that formed into
small droplet water through nozzle in desire
pressure.
• The smaller the water droplet, the higher the
ability of water spray effectiveness.
• Small droplets of water mist charging can be
created when the water is sprayed at high
pressure.

3. PROBLEM STATEMENT
• A lot of water is used to produce high water pressure.
• It wasted a lot of water and cost.
• Some researched are done to upgrade water mist system.
• Electrostatic charging method is used to approach this
problem.
• The voltage will applied into the liquid and formed very
small particle of water.
• Water pressure is used as the parameter to investigate
the effect of water pressure on the water mist system.

4. OBJECTIVES
• To study the water pressure effect on water mist.
• To study the effect of electrostatic charging
towards water mist.
• To study the relationship between the electrode-
nozzle distance with current, voltage and charge-
to-mass.
• To study the water mist separation region.

5. LITERATURE REVIEW
Advantages of using water mist system.
• The amount of water used in water mist is very
less compared using sprinkler system.
• The water mist system has very small size of
water droplet than sprinkler system.
• Water mist system low in cost compared to agent
gaseous system.

6. Water mist system Sprinkler system

7. Electrostatic charging methods
Classified into direct charging and indirect
charging.
I.Direct charging method
• For example, conduction charging method.
• Known as ‘charging by contact’.
• Connect the charged object to the neutral object.
• Risk in leaking current from nozzle to the water
tank as the nozzle configuration directly applied
with voltage.

8. II. Indirect charging method
• For example, induction charging method.
• Does not apply contact between material to the
charged object.
• More safer than conduction charging method.

9. COMPARISON OF DIRECT AND
INDIRECT CHARGING METHOD
Direct charging Indirect charging

10. METHODOLOGY
I. Water mist separation region
• To clarify the electrostatic atomization
mechanism.
• Because in the induction charging, the
generation time of drop must surpass the
charge relaxation time
I. Electrostatic atomization
• Investigate the relationship between electrode
configuration and water mist separation region.

11. Experiment Apparatus for Water Mist
Separation Region.

12. Experiment Parameter

13. Apparatus Setup for Electrostatic
Atomization Experiment

15. Flow chart of experiment

16. PROJECT ANALYSIS & DISCUSSION

17. Water mist separation region
• Higher nozzle-wire distance, d,
the higher it resistance value.
• The water mist separation
region for 0.05MPa is between
1 - 11 mm.
• The water mist separation
region for 0.10MPa is between
1 - 15 mm.
• Water mist exceed its water
surface tension limit and
caused water drop become
smaller.

18. Current versus Electrode-nozzle Distance
for 0.05 Mpa and 0.10 Mpa

19. Charge-to-mass of Water Mist
• Slightly increased and
decreased value of charge-to-
mass.
• At point 13mm fro 0.05MPa,
charge-to-mass rapidly
change.
• Due to the relationship
between current and
electrode-nozzle distance
• Consumed that chorona
discharged was determined
when spray angle of water mist
touched the ring electrode.

20. CONCLUSION
• The experiment is conducted in two different
water pressure, 0.05MPa and 0.10MPa.
• Induction method was choose as the charging
method.
• In this project, low voltage is applied rather than
high voltage.
• From the observation , low voltage produce
unstable current flow.

21. RECOMMENDATION
• The experiment should be conduct using high
voltage. The highest voltage will produce fine
water droplet than the low voltage.
• Used more high pressure to get better result.
• Additional subtopic such as investigate the water
pressure effect on spray characteristic of
electrostatic-induction water mist charging
should be suggested.

22. THANK YOU