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The University of Kansas School of Engineering Design Project A Sustainable Approach to Automobiles and Energy Infrastructure |
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2009-2010 Vehicles
Team Redline Many misconceptions with electric vehicles deal with a lack of power and speed. There are a few examples that attempt to break down these barriers, but they are very costly alternatives. The team members of the Redline EcoHawks are striving to build a hyper efficient car while keeping the production price as low as possible. While our ultimate goal is high speed, many of the same concepts apply to distance per charge and mile per gallon equivalents. By creating a car that is lightweight, aerodynamic, and dynamically efficient, a simple battery and gear change will take us from a very fast vehicle to a vehicle that is extremely energy efficient. For full size hybrid and electric vehicles to have a better chance at replacing traditional fuel dependent vehicles, they must first become more appealing to the everyday consumer. The ultimate goal of the Redline EcoHawks is to apply engineering principles and a careful design analysis to create a cost effective 1/8th scale electric vehicle capable of better performance than its internal combustion counterparts
Team Slayer
Team CellMates Team CellMates goal is to build a hydrogen fuel cell powered vehicle utilizing the most practical fuel cell technology available. We have chosen hydrogen fuel cell power in order to demonstrate it's application as a completely "green" fuel from start to finish. While the fuel cell itself is inherently clean, team CellMates will also take sustainability into consideration when producing our own hydrogen from a a renewable source, the sun, as opposed to the current fossil fuel defendant methods. We will also address problems associated with fuel cells such as price and weight by pairing a smaller fuel cell with a more efficient engine and by utilizing a metal hydride storage system, respectively. We will be modeling our vehicle as a mass transit vehicle in order to simulate a smoother transition into a hydrogen economy. Ultimately, we wish to analyze hydrogen fuel cells as a potential facet of a sustainable economy by studying them on a smaller, more economically friendly level.
Team Amp One thing Team AMP looked at when considering sustainability was appeal. We wanted to make a sustainable car that would have mass appeal and therefore a greater impact on the market. Let’s face it, not everyone wants to drive a Prius. Our goal is to build an electric luxury sedan at a more affordable price while striking a balance between performance and efficiency. One thing we’re pursuing is a space frame chassis. The Audi A8 has an aluminum space frame chassis and reported that it was 40% lighter yet 40% stiffer than a steel equivalent. By making the car lighter, we’re increasing the amount of power coming out and actually increasing the safety of the vehicle. We’re planning on creating a plug in EV. We want to place the charger on board so that the car can plug into a wall socket. We want to make it AC and DC compatible. We’re planning on using Lithium Iron Phosphate batteries. These have a lower environmental impact than their cobalt counterpart, and also have a longer cycle and calendar life. They also have the potential to charge faster without thermal runaway, and charging time is major concern with EV’s today. Ultimately, we’re looking at making a “fun to drive” plug in while keeping the cost relatively low.
Team Electric Slide Team Electric Slide has designed a plug-in electric RC car capable of running for around 36 miles modeling a full scale electric vehicle that will cost around $22,000. The focus has been to develop and implement sustainable technology into an RC car modeled after a full scale, affordable electric vehicle. The average family in The United States simply cannot afford one of the $40 to $50,000 electric or hybrid vehicles currently on the market. We as a team believe that if sustainability is going to be a plausible future, it first needs to become affordable. The components utilized have been chosen to optimize their cost and performance according to their effect on producing an affordable and marketable electric vehicle. A zero emission solar fueling station is being designed for the electric vehicle to increase the car’s sustainability. This eco-friendly and abundant energy source will help to make this electric vehicle a viable and sustainable option for the future American consumer.
Team CranoFran Team CranoFran is designing a purely electric vehicle in the mid-size sedan class and will incorporate all aspects of sustainability. We have chosen to design an electric vehicle that will utilize a solar charging station to charge the lightweight and highly efficient lithium ion batteries. The combination of a purely electric vehicle with solar energy results in a nearly carbon neutral vehicle. In order to maximize the distance per charge of the vehicle, multiple batteries must be used. To reduce the overall weight of the vehicle, a lightweight, and conductive metal will be used in the chassis design. The suspension, steering and tires will be designed to optimize both handling for consumer safety and comfort as well as efficiency. With the technology of the car headed in a new direction, we will make this visually apparent by adding subtle futuristic aspects in the body. This will allow for typically unconventional methods for reducing drag and therefore increasing the efficiency of the vehicle. |
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Scale Vehicles |
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2010-2011 Vehicles
Team Semi Electric Team Semi Electric is designing a 1/10th scale remote controlled Semi truck that will be powered by an electric motor and engine running in a parallel hybrid configuration. Our scale vehicle will be more fuel efficient than the current standard in Semi Trucks through the development of unique driveline, suspension, chassis, and body systems…
Team H2O KU Team H2O is working on designing a 1/8th scale remote control car that will run off of a hydrogen powered internal combustion engine. We are also entered in the Hydrogen Student design contest, in which we are designing a residential hydrogen fueling station. Our team consist of six main members: Samantha is our team leader and is in charge of the body design. She will work to create an aerodynamic design that will minimize drag to maximize efficiency. Kalon and Chad are the driveline team. They are creating our hydrogen powered engine and integrating all the systems to it. Mohammed is our suspension, steering, and tires member. He will choose and create our suspension system and create our remote for the remote control car. Fahad is our chassis member. He will create a stable chassis that will meet all the needs of the car. Chris is our fueling station member. He is leading the research and design of the hydrogen fueling station for the design contest. |
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Running Biofuels in RC Cars
Research: This section describes how the EcoHawks have been able to successfully run biodiesel blends in Remote Control cars. We started this effort by determining how to utilize the biodiesel created on campus from used cooking oil in the “nitro” or glow engines employed by the RC industry. One significant issue was encountered - volatility. Biodiesel is not volatile at all; hence, the small carburetors employed by the RC industry to mix fuel with air will not work with straight biodiesel. Hence, a volatile fuel must be added and stay in suspension with biodiesel. Moreover, since nitro fuel typically contains a lubricant along with the fuel, we needed to find a lubricant that could be added while additionally staying in suspension. Taking a look at typical nitro or glow fuel, we find the following: · Nitromethane (0-30%) - reactivity with NFPA 704 of 2 - health, 3 - flammability, 4 - reactivity · Castor oil (8-22%) - lubrication · Methanol (balance) - main fuel with NFPA 704 of 3 - health, 3 - flammability, 0 - reactivity We wanted to replace this fuel with our own blend that is much better for the environment and your health as a end user and handler. The two main players: · Biodiesel - main fuel with NFPA 704 of 1 - health, 1 - flammability, 0 - reactivity · Castor oil - lubrication Researching the literature, we found that n-heptane is being utilized by Sandia National Laboratories for the intended purpose of increasing diesel fuel volatility. Hence, we now have our third component to provide volatility: · n-heptane - volatility with NFPA 704 of 1 - health, 3 - flammability, 0 - reactivity We now have the makings of a fuel that can act as an analog to nitro fuel that (a) is made from used cooking oil and (b) is much better for your health. When these components were blended together, no discernable strata were seen in the mixture, even after sitting on the shelf for months. We can infer that they result in a homogeneous mixture.
Note: our research also turned up the fact that diethyl ether (NFPA - 2, 4, 1) can be used. While it is more flammable, the fact that more precautions are required when handling omitted it from our consideration. |
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Breakthrough #1: We have all the makings of a good fuel, but we did not know the correct proportions of fuel to test. To provide repeatable testing, the students built a test-stand for an RC airplane engine that we had sitting around. Through trial and error, the students were able to get a blend of 40% n-heptane, 40% biodiesel and 20% castor oil by volume to run. A couple of items found during testing: · Hot glow plug - an extremely hot glow plug (OS-6 used in the movie on the right) was required · Glow plug heater - the students needed to keep the glow plug heater attached to keep burning the fuel Unfortunately, when attempting to run this mixture in the students’ RC car, the engine would idle, but upon pulling the trigger to accelerate the vehicle, the engine would die out. Hence, more work was needed. |
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Figure 1. Testing biodiesel blends in RC airplane engine |
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A special thanks to Greg Bacon of Pratt Community College and Alan Gleue of Lawrence High School for diagnosing and troubleshooting the use of biofuels in RC car engines. Without their help, we would not have been able to achieve success. |
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Breakthrough #2: As part of a summer research program for teachers at KU, two Kansas teachers came on board to help figure out how to get an RC car to work on biofuels. Based on the previous efforts, they started the process from scratch and were able to achieve success.
Step #1: Buy an RC car. We went as inexpensive as possible in order to make this feasible for everyone. We also went with a ready-to-run kit that has everything your novice user needs to start having fun right away. Figure 2 illustrates the vehicle we purchased at a cost of $120.
Step #2: Break-in the RC engine. This is a critical step. The engines out of the box are not ready to be driven around. They need around three tanks of nitro fuel to break-in them in properly in order to achieve the proper clearances (you should read the directions that come with the vehicle).
Step #3: Buy a hotter glow plug. From our experience with breakthrough #1, we realized that the hottest glow plug would give us the best opportunity for success. Our research turned up that the four-stroke glow plugs run much hotter (tested experimentally) than the traditional two-stroke variety. Moreover, they sit a little lower in the cylinder reducing the effective compression ratio.
Step #4: Create the fuel. For our next blend, we went with a 50% n-heptane, 30% biodiesel and 20% castor oil blend by volume. We wanted to give ourselves the best shot, so we upped the n-heptane a bit.
Step #5: Try it out! It worked! As shown in Figure 4, after a bit of coaxing the car was able to start and drive around without the glow plug heater attached.
What We Learned: Throughout this process, there were a number of items that can make our (and your) lives potentially easier.
Item #1: The biodiesel blend likes it hot. While we are able to run the car without a glow plug heater, on a cold day we may not be so lucky. They do make on-board glow plug heaters for RC airplane engines. You can hook these up to one 1.2-1.5Vdc battery (or two in parallel for longer usage) very simply with an on/off toggle switch. This should reduce some of the variability possible with ambient air and make it more repeatable. |
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Figure 2. Test vehicle purchased for biofuel testing |
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Figure 3. OS-6 (left) and 4-stroke (right) glow plugs for RC engines |
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Figure 4. Successful run of biofuel in RC car engine |
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Item #2: Replace the pull starter. As you can tell by the video, it takes a bit of work to get the biodiesel blend to run consistently. This requires a bit of effort through the pull start mechanism. We are planning on replacing the pull starter with an electric starter to make our lives easier. This should definitely help with repeatability.
Item #3: Tuning the engine. There is no easy method for tuning the engine to run consistently on the biofuel blend. You just have to keep tweaking the carburetor needle valve and throttle setting to get what “looks” good to you. Putting a little nitro fuel in the carburetor to start helps the engine turn over. Adjusting the throttle trim to a higher setting (more fuel) initially and then scaling back when the engine is running is a good tact. Using your finger to cover the carburetor revving the engine (you can see Greg doing this in the video) by manipulating the air coming in helps get the engine running. After working the engine for a while, it will run consistently. There should be some “smoke” coming out of the tailpipe, but excessive smoke indicates that you are running too rich (too much fuel).
Item #4: Fuel lines. Biodiesel is thick (viscous) stuff. It does not like to move easily through the fuel lines. Adding the n-heptane helps significantly; however, it still might have issues. Therefore, you might want to go to a bigger inner diameter fuel line to eliminate this issue. Or, there might be some fuel or liquid that can be added in a very small quantity that can significantly reduce the viscosity of the mixture. Finally, watch for air in the fuel lines. Any air bubbles will cause the engine to stop working as no fuel is making it to the carburetor. |
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Next step: We would like to change our blend so it uses the maximum amount of biodiesel. This requires reducing the amount of castor oil and n-heptane. Concentrating initially on the castor oil component, we realize that biodiesel has excellent lubrication properties. So, it may be possible to replace the castor oil with biodiesel for lubricity. However, we must also consider viscosity because of item #4 above. This linked document does a great job describing the difference between lubricity and viscosity as they are not the same. From research, we find that: · ASTM D4172 (four-ball wear test) of castor oil steady-state wear = 0.56 mm · ASTM D6079 (HFRR scar test) of 100% soy biodiesel = 314 mm Unfortunately, we were unable to find a common ASTM test between the two to properly compare. However, when castor oil is used as the feedstock to create biodiesel, the ASTM D6079 test of lubricity for castor biodiesel in JP-8 (aviation) fuel (see p. 10) can be eyeballed to have an estimated HFRR scar test of about 100-150 mm if it was 100% castor biodiesel. From this, we can estimate castor oil to have about three to four times better lubricity than our used cooking oil biodiesel. Given these facts, replacing 10% castor oil with 10% biodiesel (blend: 50n/40b/10c) should be fine from a lubricity standpoint. With respect to viscosity, used cooking oil biodiesel has a viscosity of 4.47 cSt at 40°C whereas castor oil has a viscosity of 252 cSt at the same temperature. Therefore, moving to more biodiesel should help with respect to the fuel lines. Unfortunately, we just broke our test engine. We will post the results when everything is back up and running. |
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2011-2012 Vehicles
EcoFreakos Team || Hybrid |
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Energy Infrastructure |