Proposal for Super Civic Project

Transcription

1 Proposal for Super Civic Project Wentworth Institute of Technology, 2010 By M.Moore, N.Kituuma, G.Morales, & C.Zink

2 Introduction & Summary Partial hydrogen injection (PHI) is the practice of feeding a small amount of hydrogen into an internal combustion engine (ICE) through the air intake. The result is a higher power output caused by burning more of the fuel injected into the cylinder. This practice can be used to increase the fuel efficiency by decreasing the amount of fuel injected into the cylinder while maintaining the power output determined by the ICE manufacturer. There are two phases to this project. Phase One involved an extensive amount of research focused on understanding how the process works and what is required to build a reliable, effective water electrolyzer to produce the hydrogen. An electrolyzer was designed. Phase One has been completed. We now enter into Phase Two where we will build and test the system. Problem Definition Internal combustion engines (ICE) do not burn all of the fuel that is injected into the cylinders. As a result, these engines are not as efficient or as powerful as they could be. Background Research Water electrolysis is one of the many ways to produce hydrogen. This is accomplished by placing two electrically conductive solids (electrodes/plates) with opposing charges in a hydrogen rich, electrically conductive medium and passing a current from the positive to the negative electrode (see Figure1). The main components of the electrolyzer are the electrodes, the electrolyte (conductive medium), the containment vessel, and the electric power supply. To ensure that the electric current is passed from one electrode to the other, it is important to note that the housing, or containment vessel, must be an electric insulator. Figure 1: Basic Water Electrolyzer Modern water electrolysis for use in PHI systems employs the use of corrosion resistant electrode materials. Stainless steel is a common material used in less expensive systems, but has a few drawbacks. Over time, the corrosion of the electrodes leads to high concentrations of hexavalent chromium in the water/electrolyte solution, an extremely toxic carcinogen ( 2009). To avoid this, some manufacturers have moved to using more expensive titanium electrodes. However, some research shows that the hexavalent chromium only leeches out of the surface of stainless steel electrodes for a short time. Leeching stops after a period of use known as the conditioning period and may take up to a week of continuous operation to complete. We will be using 316L stainless steel in our cell, as cost is a concern.

3 The Need Today s consumers are being met with an increased need to concern themselves with fuel efficiency from an economic stand point. Solutions to this problem can include driving less, using public transportation or even purchasing a more fuel efficient vehicle. For some, these are not practical solutions. They need their current vehicle to be more fuel efficient. PHI can do this. The Objective The goal of this project is to evaluate how mixing hydrogen with the air-fuel mixture in the engine of a 1994 Honda Civic will affect the performance. The Work Plan (Methods and Evaluation) The project will begin with a second look at the design of the system. Any last concerns or modifications will be addressed at this point. After the system is constructed, ex situ tests will be performed to characterize the performance of the electrolyzer (current draw, volumetric flow of gas, operating temperature, system resistance). The unit will then be installed in a 1994 Honda Civic to evaluate the effects of PHI on an internal combustion engine. A report will be published containing the results. The Risk The analysis of this system will involve the production of hydrogen gas. The hydrogen-oxygen gas will be produced at no more than 3 liters per minute. Given the rate of gas production and the fact that hydrogen quickly rises and disperses, dangerous concentrations of hydrogen in the air are not a concern in a well ventilated area. 1 Potassium hydroxide will be used as an electrolyte. This strong alkaline base can burn the skin or make one blind when in at high concentrations. Any handling of the electrolyte solution will be conducted wearing appropriate eye and skin protection. Our electrodes will be made of 316L stainless steel. To address the concern of hexavalent chromium leeching into the electrolyte solution, all waste electrolyte solution will be bottled, labeled, and disposed of according to local regulations. 1 Hydrogen is combustible at concentrations from 4% to 74.2% by volume.

4 Team Qualifications See Appendix A for resumes. Nate - Prior knowledge of material testing after design using FEA software - Assisted professionals with documentation and project procurement Myles Moore - Proton Exchange Membrane Hydrogen Fuel Cells (1 year) o Performed various material property/behavior investigations on internal fuel cell components - Building Automation Industry (1 year) o Commissioned building control systems o Troubleshot system errors o Designed computer interface used for communicating with the control systems - Skilled Machinist o 4 years of training at Old Colony Regional Vocational Technical High School (Rochester, MA) o 1 year of experience in industry Gio - Tested several parts on a United Static Test Machine - Analyzed static and fatigue data and organized the data in a report - Machined and fabricated composite materials Courtney - Completed strength testing of various components after manufacturing - Knowledge of testing control systems Project Budget The project budget is not expected to exceed $100, as many of the components have already been acquired. Project Future (What do you see happening with this?) Partial hydrogen injection (PHI) is something that has been on the back burner of the alternative energy field since before the 1950 s. There have been many attempts to couple on-board steam reformers with combustion engines, but the major drawback of this process is its complexity. The operation of the steam reformer at a specified temperature, followed by shift conversion at a specified lower temperature, followed by water separation presents temperature and flow control problems that were considered to be too complex for an automotive application. (Cerini, 1974) As a result, much attention has been turned to water electrolysis for hydrogen production. Having the hydrogen mixed with the fuel causes a greater percentage of the fuel injected into the cylinder to be burned. These systems could eliminate the need for a catalytic converter while increasing fuel efficiency at the same time. PHI is could be a potential solution to responsible use of our petroleum resources.

5 Bibliography Cerini, J. H. (1974). On-Board Hydrogen Generator for a Partial Hydrogen Injection Internal Combustion Engine. New York, New York: Society of Automotive Engineers, Inc. (2009, Dec. 28). Retrieved from

6 Appendix A

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10 Figure 2: Work Plan - page 1 of 2

11 Figure 3: Work Plan - page 2 of 2