Wet Cell Anatomy Electrode housing also acts as the reservoir Electrodes are fully or partially submerged in electrolyte solution Edges of the electrode plates are open to the electrolyte bath Tend to be very inefficient
Current Leakage The biggest flaw in a wet cell system is the current loss through the edges of the electrode plates. The electrolyte being charged outside of the active area of the cells plates does not produce hydrogen. This current leakage makes the wet cell very inefficient.
Dry Cell Anatomy Electrolyte reservoir is separated from the cell and is also used as a bubbler for the HHO gas Holes in the cell plates allow for the electrolyte solution to travel through the system and gas to exit Greatly increases efficiency by reducing parasytic current loss that occurs at the edges of the plates By having a constant circulation of the electrolyte solution through the cell, we decrease the operating temperatures
Electrolytes What is an electrolyte? Why do we need to use an electrolyte? What different types of electrolytes do we have to choose from? Why did we choose what we did?
Why did we choose KOH? Advantages: Electrodes stay clean due to KOH’s minimal reactive nature with 316L Stainless Steel. Strong and pure electrolyte. Found readily available at Home Depot. Disadvantages: Dangerous to work with. KOH (s) → K + (aq) + OH – (aq)
System Design Criteria Component materials MUST… – be resistant to corrosion in electrolyte solution. – perform well in temperatures ranging from -20 °C to upwards of 70 °C. –maintain structural integrity under compressive load. Low electrical resistance through stack.
Gasket Sealing Load D = diameter P = ρgh = max pressure in vessel b = gasket width
Gasket Deformation Under Load F = force L = gasket thickness A = area of gasket E = gasket modulus of elasticity
Given more time, we would… Analyze the engine performance with and without stack. Play with electrode hole sizing and placement to find the best balance between flow through cell, greatest surface area, and least amount of current leakage. Tested many different electrolyte solutions to determine the most optimal one for our application. Tested the system in a car if the results in a controlled environment proved significant enough to be worthwhile. Had the dry cell professionally machined and assembled with the exact parts and materials specified. Conclusion In conclusion we were successful in the objectives we sought after which were to investigate partial hydrogen injection and the effects it would have on an internal combustion engine. Our cell has proved to produce a significant amount of hydrogen and through our thorough research we have determined that it would increase the efficiency of an internal combustion engine.
B IBLIOGRAPHY 1. Zero. FAQ. Zero Fossil Fuel. [Online] [Cited: March 30, 2010.] http://alt- nrg.org/faq.html. 2. HHO Generator Resource Center. [Online] Dec. 28, 2009. [Cited: Feb. 5, 2010.] http://www.hhogenerator.com/hho-and-the-energy-market-olympic-hydrogen-ti-hho- generators/. 3. Chemical Compatability. Cole-Palmer. [Online] [Cited: Feb. 3, 2010.] http://www.coleparmer.com/techinfo/ChemComp.asp. 4. Dorf, Richard C. The Engineering Handbook, Second Edition. 2004. ISBN 978-0-8493- 1586-2. 5. Cerini, John Housman and D.J. On- Board Hydrogen Generator for a Partial Hydrogen Injection Internal Combustion Engine. New York, New York : Society of Automotive Engineers, Inc., 1974. 6. Mott, Robert L. Machine Elements in Machine Design, Fourth Edition. Upper Saddle River, New Jersey : Pearson Education, Inc., 2004. ISBN 0- 13-161885-3. 7. MatWeb. [Online] [Cited: Feb. 4, 2010.] http://www.matweb.com.