24
6-Stroke
Project Proposal and Feasibility Study
11 December 2009
Team 14
John Mantel
Andrew DeJong
Tim Opperwall
Marc Eberlein
Jim VanLeeuwen
Executive Summary
Fossil fuels are being used at an alarming rate and unconventional methods need to be considered to help reduce the dependence on these fuels. The goal of this project is to increase the efficiency of a standard internal combustion engine. This will effectively reduce fuel consumption, and therefore emissions, without significantly compromising on power. To accomplish this, a four stroke engine will be modified to a six stroke engine by adding a steam cycle, such that the engine (1) intakes, (2) compresses, (3) combusts, (4) recompresses, (5) injects water, (6) exhausts.
The project is split up into three major subcomponents.
· The injection system will be designed and implemented to be able to inject a precise amount of water at a specific time. An electronic engine control unit (ECU) will adjust the amount of water injected based on the temperature of the engine. If the engine is running too hot, more water will be injected.
· The current camshaft and valves will be removed. The ECU will use a crankshaft position sensor to monitor the engine’s rotation and control the timing on overhead electronic valves.
· Calculations and experiments will determine the amount of water to inject per cycle and the relative efficiency of the engine. Power and fuel consumption tests will be conducted before and after the modification to verify these calculations.
The budget for this project is projected to be approximately $825. However, this is offset by purchasing the water injection control system through a project in ENGR 315. Consequently the effective budget for ENGR 339 is $675.
This semester long feasibility study determined the above ECU method as a feasible project and will be implemented in Engineering 340 to achieve the design goals.
Table of Contents
Table of Contents 2
1. Introduction Error! Bookmark not defined.
1.1 Team Profile 4
1.1.1. Tim Opperwall 4
1.1.2. Andrew DeJong 4
1.1.3. John Mantel 4
1.1.4. Jim VanLeeuwen 4
1.1.5. Marc Eberlein 4
1.2 Project Motivation 5
1.3 Project Description 5
2. Project Objectives 5
2.1 Design Objectives 5
2.2 Design Norms 5
2.2.1. Transparency and Integrity 5
2.2.2. Stewardship 6
3. History and Research 6
3.1 Existing Patents 6
3.1.1. US Patent 1339176 – May 4, 1920 6
3.1.2. US Patent 3964263 – June 22, 1976 6
3.1.3. US Patent 4736715 – April 12, 1988 6
3.1.4. US Patent 6253745 – June 3, 2001 6
3.1.5. US Patent 6311651 – November 6, 2001 6
3.2 Recent Work 6
3.2.1. Bruce Crower’s Engine 6
4. Testing 7
4.1 Dynamometer Testing 7
4.2 Emissions Testing 7
4.2.1. Orsat Testing 7
4.2.2. Gas Chromatography 8
4.3 Fuel Consumption 8
5. Thermodynamic Analysis 8
6. Water Injection System 10
7. Design Alternatives 12
7.1 Design A: Camshaft Design 12
7.2 Design B: Electronic Control System 14
7.3 Budget Analysis 16
7.4 Decision Matrix 16
8. Project Management 17
8.1 Task Delegations 17
8.1.1. Controls 17
8.1.2. Thermodynamics 17
8.1.3. Cam Analysis 17
8.1.4. Testing 17
8.1.5. Inventor modeling 18
8.1.6. Website 18
9. Conclusion 18
10. Special Thanks 19
10.1 Ren Tubergen 19
10.2 Ned Nielsen 19
10.3 Nick Hendriksma 19
10.4 Paulo Ribeiro 19
10.5 David Benson 19
10.6 Gary Geukes 19
11. Appendix A Error! Bookmark not defined.
12. References 24
1. Team Introduction
From left: Tim Opperwall, John Mantel, Andrew DeJong, Marc Eberlein, and Jim VanLeeuwen.
1.1 Team Profile
1.1.1. Tim Opperwall
Timothy Opperwall is from Grandville, Michigan and will be graduating with a Bachelors degree in Engineering with a mechanical concentration. He is looking into Mid-West graduate programs as well as employment in the West Michigan area.
1.1.2. John Mantel
John Mantel is from Chelsea, Michigan and will be graduating with a Bachelors degree in Engineering with a mechanical concentration. He is pursuing professional basketball opportunities in Europe but has plans to return to the engineering field in the future.
1.1.3. Andrew DeJong
Andrew DeJong is from Grand Rapids, Michigan and will be graduating with a Bachelors degree in Engineering with a mechanical concentration. He is pursuing graduate school in the Washington, D.C. area.
1.1.4. Marc Eberlein
Marc Eberlein is from Jamestown Township, Michigan and will be graduating with a Bachelors degree in Engineering with a mechanical concentration. He is currently employed at Highlight Industries and hopes to continue working there full time after graduation.
1.1.5. Jim VanLeeuwen
Jim VanLeeuwen is from Jenison, Michigan and will be graduating with a Bachelors degree in Engineering with a mechanical concentration. He is actively seeking full time employment opportunities in both manufacturing and design.
2. Project Introduction
2.1 Project Motivation
The modern world is driven by fossil fuels. Consequently, society has been consuming exhaustible resources at an ever increasing rate. There are many possible long term solutions including nuclear, hydroelectric, solar and geothermal energy sources. However, these solutions cannot be realistically implemented quickly and effectively. In the short term, unconventional and hybrid solutions must be implemented to reduce the consumption of fossil fuels and provide more valuable time for the long term solutions to be implemented. The goal of this project is to increase the efficiency of a standard internal combustion engine. This will effectively reduce fuel consumption, and therefore emissions, without compromising on power.
2.2 Project Description
To further the research in short-term, unconventional solutions, a one cylinder, four-cycle, 16-horsepower, internal combustion engine will be modified with the goal of higher efficiency. The modified engine will run six cycles by adding a water injection and an exhaust cycle to the end of the traditional four cycles. The first four strokes will be an intake, compression, combustion, and exhaust identical to the original engine. In the fifth stroke, water will be injected into the hot cylinder and will expand into steam. In the sixth stroke, the steam and leftover combustion gases will be exhausted. The modified engine will be more efficient because the fifth stroke is a second power stroke that uses heat otherwise lost to the atmosphere.
3. Project Objectives
3.1 Design Objectives
The main objective for this project is a working six-stroke internal combustion engine. The desired outcome is to observe decreased fuel consumption for the same power output. Along the way, a number of intermediate goals will be set to track progress and analyze risks. The specifics of these goals are further discussed in the Camshaft Design and Electrical Control System sections.
3.2 Design Norms
As Christian engineers, this team needs to consider more than just time and money in the decision making process. Design norms, such as transparency, integrity, and stewardship will be included in every decision.
3.2.1. Transparency and Integrity
This project is part of larger research with the goal of greater efficiency. Withholding data and calculations, or reporting falsified or incomplete data, is not conducive to advancing research. Researchers and users of this technology need to know that it will work. Consequently, a large part of this project will be thoroughly documenting all the calculations and modifications. All our progress and data will be documented and made public.
3.2.2. Stewardship
It is the responsibility of all Christians (including Calvin College, its students, and this team) to use natural resources in way that honors God. The way fuels are currently used can be improved to better protect resources. Increasing fuel efficiency is one way the team can respond to this calling.
4. History and Research
4.1 Existing Patents
4.1.1. US Patent 1339176 – May 4, 1920
Leonard H Dyer patented the basic idea of using a water injecting fifth stroke to increase efficiency and simplify the cooling of an internal combustion engine.[1]
4.1.2. US Patent 3964263 – June 22, 1976
Robert C Tibbs expanded on Dyer’s patent to include a piston with a higher heat capacity and an exhaust system that condenses and filters the water after it is exhausted from the cylinder.[2]
4.1.3. US Patent 4736715 – April 12, 1988
Gregory J. Larsen patented a 6-stroke engine that supercharges and reheats the intake air. The two intake ports for the cylinder are cam actuated. [3]
4.1.4. US Patent 6253745 – June 3, 2001
US Patent 6311651 – David M Prater patented a six stroke engine that contains the combustion products in a separate heat regenerator, injects water into the regenerator, and then opens the regenerator to the cylinder, providing another power stroke.[4]
4.1.5. US Patent 6311651 – November 6, 2001
Satnarine Singh patented a six stroke engine with a computer controlled water injection system. The patent calls for a turbine that removes additional energy from the exhaust steam and a condenser that recycles the used water.[5]
4.2 Recent Work
4.2.1. Bruce Crower’s Engine
Bruce Crower, owner of Crower Cams and Equipment Company, modified a four-stroke diesel engine to run a six-stroke cycle similar to the one proposed in this project. His ran for over an hour and was only warm to the touch.[6] Crower was not available for comment due to medical issues.
5. Testing
5.1 Dynamometer Testing
To determine if power is maintained, increased, or reduced, testing of the engine will be conducted on the unmodified and modified engine cycles. This testing aids in determining the level of success of the project.
In an attempt to do preliminary testing of the unmodified engine, the group contacted Gary Geukes at Fastbikes USA, a local business that was willing to test the engine on its motorcycle dynamometer. To test the engine, the team attached a small tire to the engine and built a frame to hold the engine steady during the testing.
Unfortunately, since this dynamometer was designed for high-power motorcycle engines, the unmodified engine was unable to provide enough torque to spin the dynamometer at a speed high enough to prevent stalling. Consequently, the unmodified engine stalled every time it contacted the dynamometer.
Ren Tubergen, the industrial consultant for this project, provided contact information for John Farris in the Grand Valley State University engineering department. Mr. Farris has access to a small engine dynamometer used to test engines in the Baja. Mr. Farris has not responded to the team’s attempts to contact him.
At this time, attempts to test the unmodified engine have been placed on hold to allow other areas of the project to continue moving forward.
5.2 Emissions Testing
To analyze the efficiency of combustion in the engine, the concentrations of the combustion products in the exhaust gases must be determined. The two methods explored to accomplish this were Orsat testing and gas chromatography.
5.2.1. Orsat Testing
In Orsat testing, the exhaust gasses are piped through separate containers filled with different solutions (potassium hydroxide, pyrogallol, etc). As the gasses pass through the solutions, specific combustion products (carbon monoxide, oxygen, etc) are absorbed into the solutions, reducing the volume of the emission gases.[7] From this we can calculate the composition of the emission gases. Professor Sykes suggested that Materials Testing Consultants might be able to conduct an Orsat test on the unmodified engine. However, they do not have the facilities for this type of test. Research into other possible venues for this test has been unsuccessful.
5.2.2. Gas Chromatography
After contacting Calvin’s chemistry department, Professor David Benson has suggested that gas chromatography could be used to analyze the exhaust gases. He was also optimistic that this test could be performed using Calvin’s existing equipment. Gas chromatography passes the exhaust gases through a capillary tube containing a silicone solid. As the gases are forced through the solid, the components separate out in a predictable order. Gas chromatography is most often used for environmental monitoring and industrial chemical fields.[8],[9],[10]
5.3 Fuel Consumption
To determine the change in fuel consumption, tests will be run before and after the engine modifications. These tests will observe the amount of fuel consumed to achieve a certain amount of work. A likely way to do this would be to drive a water pump to move water from one place to another. This would require a quantifiable amount of work and the power could be controlled by a valve on the water flow. Another way would be to simply measure the fuel consumption at a known power during the dynamometer testing.
6. Thermodynamic Analysis
Each of the six stages of the six-stroke operation will be broken down into thermodynamic states to find critical unknowns in the design process. These occur after each of the six strokes. Because the engine is an open system, the thermodynamic state before the intake must be examined to take into account atmospheric conditions. So there are seven thermodynamic states to be examined.
These thermodynamic calculations will determine the amount of water injected during the fifth stroke. The appropriate heat reduction and steam content are crucial variables. Having the correct amount of water injected into the system will insure that the right amount of heat is removed by turning the water into steam. This sudden expansion provides additional power.
For the thermodynamic state directly before intake, atmospheric conditions are assumed (22 °C and 101 kPa). This defines the first thermodynamic state.
Directly after intake, the pressure is assumed to still be atmospheric. The volume of the air will be determined from the dimensions of the cylinder. The amount of gasoline in the cylinder will be determined by the fuel consumption test. By measuring fuel consumption over a specific amount of time over a constant, known, drive shaft speed the fuel consumption per cycle will be calculated. This defines the second thermodynamic state.
For the third thermodynamic state, after compression, three variables are known: the volume and pressure of the air in the cylinder, and the mass of the gasoline in the cylinder. The volume and pressure will be calculated assuming ideal gas properties and using the compression ratio for the cylinder. The mass of gasoline used was known after the second thermodynamic state and this amount will not have changed with compression. The variable that will be unknown is the temperature of the air inside the cylinder. The proposed method for finding this temperature is to place two thermocouples in the head at known distances from the inside face of the cylinder. Since there will be a linear regression from the temperature inside the cylinder to the temperature of the outside air, the two known temperatures will be calibrated to find the unknown temperature inside the cylinder. This defines the third thermodynamic state.