User talk:BALARAM PANIGRAHY

* '''IJMIE Volume 2, Issue 6 ISSN: 2249-0558 * ___________________________________________________________ * A Monthly Double-Blind Peer Reviewed Refereed Open Access International e-Journal - Included in the International Serial Directories * Indexed & Listed at: Ulrich's Periodicals Directory ©, U.S.A., Open J-Gage as well as in Cabell’s Directories of Publishing Opportunities, U.S.A. * International Journal of Management, IT and Engineering * http://www.ijmra.us * 417 * June * 2012 * INTEGRATION OF EC & IC ENGINE’S WORKING * Abhimanyu Joon* * B.S.Patel** * __________________________________________________________ * Abstract: * It is known that when any kind of fossil fuel is burnt two phenomenons take place (i) Explosion * and (ii) Heat generation. In the concept that is stated it is desired to merge the functioning of * External Combustion (EC) and Internal Combustion (IC) engines on the basis of their working * principle. In an EC engine the motive power is obtained by utilizing the factor of heat alone, * which results in vaporization of a fluid that is used to move the piston inside the cylinder piston * arrangement. Whereas in an IC engine the motive power is derived form the explosion factor, * which takes place inside a control volume, thereby providing the necessary power to push the * piston for obtaining the desired working motion. It is important to note that neither EC nor IC * engines have efficiency greater than 40%. This is due to the fact that neither of the system utilizes * both the factors mentioned above, for producing useful work. But if we can utilize the heat * produced due to combustion of fuel in an IC engine, based on the working principle of EC engine, * to supply motive power, then we can assure that maximum output would be derived. This paper * aims at justifiable use of energy by the combination of the working principles of EC engines used * in locomotives and IC engines powered by gasoline (petrol). * Keywords: External Combustion (EC) engine, Otto cycle, Electronic water pump, Hybrid * vehicle, Water jacket, Liner. * * * Post Graduate Student, ME-Machine Design (Final Year) * ** Associate Professor, Mechanical Engineering Department * Birla Vishvakarma Mahavidyalaya, Vallabh Vidyanagar, Gujarat, India. IJMIE Volume 2, Issue 6 ISSN: 2249-0558 * ___________________________________________________________ * A Monthly Double-Blind Peer Reviewed Refereed Open Access International e-Journal - Included in the International Serial Directories * Indexed & Listed at: Ulrich's Periodicals Directory ©, U.S.A., Open J-Gage as well as in Cabell’s Directories of Publishing Opportunities, U.S.A. * International Journal of Management, IT and Engineering * http://www.ijmra.us * 418 * June * 2012 * 1. Introduction * 1.1 Types of Engine * Engines can be basically classified according to the manner in which the fuel is burnt. * * Fig. 1.1 Concept of EC engine * If fuel is burnt outside the cylinder-piston arrangement then such an engine is called “External * Combustion Engine”. * Fig. 1.2 Concept of IC engine * If the fuel is burnt inside the cylinder-piston arrangement then such an engine is called * “Internal Combustion Engine”. IJMIE Volume 2, Issue 6 ISSN: 2249-0558 * ___________________________________________________________ * A Monthly Double-Blind Peer Reviewed Refereed Open Access International e-Journal - Included in the International Serial Directories * Indexed & Listed at: Ulrich's Periodicals Directory ©, U.S.A., Open J-Gage as well as in Cabell’s Directories of Publishing Opportunities, U.S.A. * International Journal of Management, IT and Engineering * http://www.ijmra.us * 419 * June * 2012 * 1.2 Working of External Combustion Engine * External Combustion engine operates by converting heat energy into mechanical energy. This * requires a heat source, a boiler to generate steam and cylinders converting the thermal energy * contained in steam to mechanical energy, which can be used to perform work. Steam is * technically defined as being elastic aeriform fluid in which water is converted when heated to * its boiling point. The steam is condensed upon contact with cool air and brought back to its * liquid state. The cycle of external combustion consists of 2-strokes of piston or one revolution * of flywheel. *  During 1st stroke pressurized steam is diverted towards the top of cylinder through a slide * valve, which pushes the piston backward *  In the 2nd stroke steam is diverted towards the bottom of the piston which pushes it forward * Fig. 1.3 Working of EC engine * 1.3 Working of Internal Combustion Engine * Internal Combustion engine operates by converting explosion of a mixture of air and fuel into * mechanical energy. This requires a technique of mixing specific quantity of fuel with air, * method of igniting the mixture and a process of removing the product of combustion. * In any IC engine the combustion of mixture takes place in a space known as „combustion * chamber‟ which is the empty volume between the head of a cylinder and the top of a piston * that reciprocates inside that cylinder. IJMIE Volume 2, Issue 6 ISSN: 2249-0558 * ___________________________________________________________ * A Monthly Double-Blind Peer Reviewed Refereed Open Access International e-Journal - Included in the International Serial Directories * Indexed & Listed at: Ulrich's Periodicals Directory ©, U.S.A., Open J-Gage as well as in Cabell’s Directories of Publishing Opportunities, U.S.A. * International Journal of Management, IT and Engineering * http://www.ijmra.us * 420 * June * 2012 * The cycle of internal combustion consists of 4-strokes of piston or two revolution of * crankshaft. *  In 1st stroke air-fuel mixture is sucked inside the cylinder piston arrangement through inlet * valve *  In 2nd stroke the piston compresses this mixture *  In 3rd stroke spark plug produces a spark which explodes the compressed air-fuel mixture *  In 4th stroke the piston removes the gases produced due to combustion by pushing them out * through the exhaust valve * Fig. 1.4 Working of IC engine * 1.4 Challenges in present day Engines * At the moment the engine technology is faced with challenges such as: * 1. Low efficiency: The efficiency of IC engines is up to 37% in spite of aiding them with turbo * charger, supercharger or stock efficiency aids, but it is better than that of an EC engine used in * auto vehicles which is around 15%. IJMIE Volume 2, Issue 6 ISSN: 2249-0558 * ___________________________________________________________ * A Monthly Double-Blind Peer Reviewed Refereed Open Access International e-Journal - Included in the International Serial Directories * Indexed & Listed at: Ulrich's Periodicals Directory ©, U.S.A., Open J-Gage as well as in Cabell’s Directories of Publishing Opportunities, U.S.A. * International Journal of Management, IT and Engineering * http://www.ijmra.us * 421 * June * 2012 * 2. High fuel consumption: The mileage given by different category of vehicles such as 2- * wheelers, 3-wheelers, 4-wheelers varies in a descending order by a large magnitude. The * mileage of 2-wheelers is mostly around 70 kilometers per liter of fuel; whereas that for 3- * wheelers is less than 50 kilometers per liter of fuel and that for 4-wheelers it lies between 18 * to 20 kilometers per liter. * Fig. 1.5 Two-wheeler, Three-wheeler & Four-wheeler * 3. Under utilization of energy: None of the working principles; neither of external combustion * nor of internal combustion concentrates on benefiting from the entire energy that is available * from the specific quantity of fuel that is burned. The EC engines utilize only the heat available * from the combustion process while the IC engines derive the necessary power from the factor * of explosion only. * 4. Significant air pollution: The auto-vehicles emit a large portion of unwanted and harmful * gases as the product of burning of fuel. The gases so produced are a mixture of carbon * dioxide, carbon monoxide, Nitrogen oxide and suspended particulate material that contribute * to the green house effect making average surrounding temperature to increase above normal * value. * * Fig. 1.6 Contribution to air pollution IJMIE Volume 2, Issue 6 ISSN: 2249-0558 * ___________________________________________________________ * A Monthly Double-Blind Peer Reviewed Refereed Open Access International e-Journal - Included in the International Serial Directories * Indexed & Listed at: Ulrich's Periodicals Directory ©, U.S.A., Open J-Gage as well as in Cabell’s Directories of Publishing Opportunities, U.S.A. * International Journal of Management, IT and Engineering * http://www.ijmra.us * 422 * June * 2012 * 1.5 Mandatory Improvements * It is essential to carry out certain improvements such as: * 1. Maximization of output: This highlights that whatever quantity of fuel is poured into the * engine, must be utilized to maximum possible extent without any kind of wastage. * 2. Utilization of waste energy: In order to make engines more effective a mechanism must be * developed to tap that portion of energy which has been lost without being effectively utilized. * 3. Technique to improve efficiency: It is suggested that other than making complete alteration in * the design of engines for making them more efficient, those aspects which compromise * efficiency must be addressed. * 4. Reducing Green House Effect: We must create such a system that decreases the toxicity of tail * pipe emissions, reduces the temperature of the exhausted by- products and contributes in * preserving the environment. * 1.6 Outcome of Integration of EC & IC Engines * The following advantages are achieved if the two principles of working are combined * 1. Maximum utilization of generated energy: * By clubbing the two arrangements together we can ensure that energy loss of IC cylinder * piston arrangement can be used as a source of power for driving the EC cylinder piston * arrangement that would supplement the function of IC engine. * 2. Decrease in overall fuel consumption: * As a combination of both the arrangements would be used to produce the necessary power for * doing useful work, such an arrangement would seal off any wastage of energy occurring * otherwise. IJMIE Volume 2, Issue 6 ISSN: 2249-0558 * ___________________________________________________________ * A Monthly Double-Blind Peer Reviewed Refereed Open Access International e-Journal - Included in the International Serial Directories * Indexed & Listed at: Ulrich's Periodicals Directory ©, U.S.A., Open J-Gage as well as in Cabell’s Directories of Publishing Opportunities, U.S.A. * International Journal of Management, IT and Engineering * http://www.ijmra.us * 423 * June * 2012 * 3. Improvement in performance: * The duration of operation of an engine working on such an arrangement would be increased * due to the combined effect. Thus the period of effectiveness of the machinery is increased * which would be beneficial in the long run. * 4. Reduction in temperature of exhaust gases: * In conventional IC engines the high temperature of exhaust gases is a major contributor of * rising the surrounding atmospheric temperature. In case we are able to utilize this heat for * providing the necessary energy to an associated EC engine then it would contribute in * lowering the exhaust gas temperature hence reducing their share in increasing the green house * effect. * 2. Stimulus for Exploration * 2.1 Motivation * (1) Studied the working principles of EC & IC engines: * While studying the principles on how EC and IC engines work, the demerits of both the * approaches surfaced, which provided the basis of research * (2) Identified myopic efficiency: * Otto cycle is typically used for car‟s internal combustion engine that works using gasoline as a * fuel. IC engines that are based on 4 strokes of the „Otto cycle‟ have one power stroke for * every four strokes, which is a significant reason behind the reduced efficiency. IJMIE Volume 2, Issue 6 ISSN: 2249-0558 * ___________________________________________________________ * A Monthly Double-Blind Peer Reviewed Refereed Open Access International e-Journal - Included in the International Serial Directories * Indexed & Listed at: Ulrich's Periodicals Directory ©, U.S.A., Open J-Gage as well as in Cabell’s Directories of Publishing Opportunities, U.S.A. * International Journal of Management, IT and Engineering * http://www.ijmra.us * 424 * June * 2012 * Fig. 1.7 Cycle of IC engines * (3) Realized the limited usage of energy: * Neither of the two working approaches of EC or IC makes efficient use of the entire energy * which is available after the burning of fuel. * (4) Decided to obtain combined result: * In order to wok-out a suitable mechanism to reutilize the waste heat exhausted from an IC * arrangement and to channelize this energy for supporting its working the decision to integrate * the two concepts was taken. * 2.2 Objectives * The shortlisted objectives of the research work to be achieved are as follows: * a) To increase overall efficiency of an IC engine * b) To achieve maximum possible output from a given input, in an engine * c) To minimize the consumption of fuel * d) To decrease the wastage of energy available from fuel, in existing engines * e) To re-utilize the wasted energy IJMIE Volume 2, Issue 6 ISSN: 2249-0558 * ___________________________________________________________ * A Monthly Double-Blind Peer Reviewed Refereed Open Access International e-Journal - Included in the International Serial Directories * Indexed & Listed at: Ulrich's Periodicals Directory ©, U.S.A., Open J-Gage as well as in Cabell’s Directories of Publishing Opportunities, U.S.A. * International Journal of Management, IT and Engineering * http://www.ijmra.us * 425 * June * 2012 * 3. Work done so far * 3.1 Cooling System Components * A conventional cooling system consists of four major components: * i) Radiator * ii) Water Pump * iii) Thermostat valve * iv) Water Jacket * Fig. 3.1 Cooling System of IC engine * 3.2 Working * The water is pumped by water pump from the water tank into the engine‟s water jacket but * until the temperature of engine reaches a value of 93⁰C the Thermostat valves does not allow * water to enter the radiator and by-passes it through the by-pass valve for recirculation IJMIE Volume 2, Issue 6 ISSN: 2249-0558 * ___________________________________________________________ * A Monthly Double-Blind Peer Reviewed Refereed Open Access International e-Journal - Included in the International Serial Directories * Indexed & Listed at: Ulrich's Periodicals Directory ©, U.S.A., Open J-Gage as well as in Cabell’s Directories of Publishing Opportunities, U.S.A. * International Journal of Management, IT and Engineering * http://www.ijmra.us * 426 * June * 2012 * Fig. 3.2 Working of IC engine cooling system * 3.3 New Arrangement * In the new arrangement the flow rate of water is very low compared to conventional cooling * systems, which is regulated by the water pump. The slow flow rate of water ensures the more * time is available between the flowing water and the outer wall of liner for obtaining maximum * heat transfer to take place thereby ensuring phase change. The steam so generated is diverted * to the EC cylinder piston arrangements where it is used for obtaining useful work. * Fig. 3.3 New Concept for Cooling System IJMIE Volume 2, Issue 6 ISSN: 2249-0558 * ___________________________________________________________ * A Monthly Double-Blind Peer Reviewed Refereed Open Access International e-Journal - Included in the International Serial Directories * Indexed & Listed at: Ulrich's Periodicals Directory ©, U.S.A., Open J-Gage as well as in Cabell’s Directories of Publishing Opportunities, U.S.A. * International Journal of Management, IT and Engineering * http://www.ijmra.us * 427 * June * 2012 * 3.4 Calculations *  Flow rate of coolant or water varies with engine‟s speed *  Diameter of crankshaft pulley, Dc = 12cm *  Diameter of water pump pulley, Dw = 11cm * Table 1: Water flow rate corresponding to engine speed * Crankshaft * pulley’s * rpm * Water pump * pulley’s rpm * Flow rate, * liter/s * 900 983 2.77 * 1000 1092 3.08 * 2500 2730 7.70 * 5000 5459 15.41 * 3.5 Typical Data *  Temperature inside combustion chamber during power-stroke is nearly = 1400⁰C *  Maximum possible heat transferred to the liner is nearly = 40% *  Preferable temperature of liner = 250⁰C *  Actual temperature of liner is nearly = 602⁰C *  Pressure within the cooling system = 103.42 KPa *  Boiling point of water under this pressure = 125⁰C IJMIE Volume 2, Issue 6 ISSN: 2249-0558 * ___________________________________________________________ * A Monthly Double-Blind Peer Reviewed Refereed Open Access International e-Journal - Included in the International Serial Directories * Indexed & Listed at: Ulrich's Periodicals Directory ©, U.S.A., Open J-Gage as well as in Cabell’s Directories of Publishing Opportunities, U.S.A. * International Journal of Management, IT and Engineering * http://www.ijmra.us * 428 * June * 2012 * For ensuring that the flowing water converts into steam, the required flow rate will be as * under: * Heat lost by liner = Heat gained by flowing water (from „energy balance equation‟) * Q = mw.Cp-w.(T1-T2) * h.A.(Ts- Tf) = mw.Cp-w.(T1-T2) * i) For h = 1600 W/m²-K; mw = 129 milliliters/s (Lower Limit) * ii) For h = 2000 W/m²-K; mw = 180 milliliters/s (Upper Limit) * Remark: This flow rate can be achieved by using either an „electronic water‟ pump or by * „changing‟ the „diameter of pulley‟ of the mechanically operated water pump. * 3.6 Integrated Engine * As compared to a conventional IC engine, the engine that would be able to generate power for * propulsion, by the combustion of fuel, according to Otto cycle and makes use of the energy * escaping through the cooling system in the form of heat to do useful work will be referred as * „Integrated engine‟, as shown in Fig. 3.3. For the concerned research work the selected * configuration of cylinder-piston arrangements for the integrated engine will the „3 cylinder * Inline’. In which the second cylinder would function as IC cylinder while the first and third * cylinders would work in a fashion similar to EC engine‟s cylinders. * It is proposed that for a brief initial period, when the engine is started, the sole IC cylinder * would support the movement of the two EC cylinders till steam generation takes place due to * boiling and resulting phase change of the circulating cooling water in the water jacket. So it is * imperative for the sole IC cylinder to generate sufficient power for sustaining the load of the * two EC cylinder-piston arrangements. So taking into consideration the smallest bore size * available for engines used in a four wheeler, the most favorable bore diameter for the IC * cylinder of the integrated engine was identified as under. IJMIE Volume 2, Issue 6 ISSN: 2249-0558 * ___________________________________________________________ * A Monthly Double-Blind Peer Reviewed Refereed Open Access International e-Journal - Included in the International Serial Directories * Indexed & Listed at: Ulrich's Periodicals Directory ©, U.S.A., Open J-Gage as well as in Cabell’s Directories of Publishing Opportunities, U.S.A. * International Journal of Management, IT and Engineering * http://www.ijmra.us * 429 * June * 2012 * Table 2: Bore diameter versus Power developed * Bore * diameter, * cm * Increase in * diameter, * cm * Power developed, * KW * Power enhances * by, * % * 6.85 - 2.941 - * 7.85 1.0 3.862 31.31 * 8.05 1.2 4.061 38.08 * 8.85 2.0 4.909 66.91 * From the above tabulated data it can be commented that increasing bore diameter by 2.0 cm * gives most optimized results for the power developed, by the engine. Hence for the sole IC * cylinder of the integrated engine the bore diameter of 8.85 cm is selected. * * Corresponding to this value of bore diameter the other related parameters obtained by * considering the total engine volume to be equal to 0.8 liters, are as follows: * 1) Swept volume of the sole IC cylinder = 442.67cm³ * 2) Mass of fuel injected in sole IC cylinder = 0.00648 Kg/s * 3) Swept volume of each EC cylinder = 178.665cm³ * 4) Bore diameter of each EC cylinder = 5.62cm * The contribution of the generated steam in the form of EC cylinders in doing useful work is as * under: * i) Pressure of steam inside the system = 103.420 KPa * ii) Surface area of piston on which steam would act = 24.791cm² IJMIE Volume 2, Issue 6 ISSN: 2249-0558 * ___________________________________________________________ * A Monthly Double-Blind Peer Reviewed Refereed Open Access International e-Journal - Included in the International Serial Directories * Indexed & Listed at: Ulrich's Periodicals Directory ©, U.S.A., Open J-Gage as well as in Cabell’s Directories of Publishing Opportunities, U.S.A. * International Journal of Management, IT and Engineering * http://www.ijmra.us * 430 * June * 2012 * iii) Force developed by steam pressure = 256.409 N * iv) Force available at crankshaft = 238.461 N * v) Combined effort of two EC cylinders = 476.922 N * vi) Power produced by two EC cylinders = 28.616 Watt * Hence the features of the integrated engine are: * (1) Maximum power output, bhp = 4.937 KW * (2) Mechanical efficiency, ηm = 80% * (3) Thermal efficiency, ηbt = 34.35% * (4) Specific fuel consumption, bsfc = 0.2381 Kg/KW-h * 3.7 Case Study * In order to determine the practical applicability of the concept of combining together working * principles of EC and IC engines, a case study of a vehicle, from the Indian auto market is * taken up. The vehicle is Maruti 800 car which is appreciated for its superior fuel economy. * Two tests were conducted on the engine of this vehicle whose results are as under: * (1) Result of Morse Test for Maruti 800 engine * (i) Indicated power available= 11.028 KW *  (ii) Indicated power per cylinder = 3.676 KW *  (iii) Brake power available = 8.823 KW *  (iv) Brake power per cylinder = 2.941 KW *  (v) Mechanical efficiency = 80% * (2) Result of Performance Test for Maruti 800 engine: IJMIE Volume 2, Issue 6 ISSN: 2249-0558 * ___________________________________________________________ * A Monthly Double-Blind Peer Reviewed Refereed Open Access International e-Journal - Included in the International Serial Directories * Indexed & Listed at: Ulrich's Periodicals Directory ©, U.S.A., Open J-Gage as well as in Cabell’s Directories of Publishing Opportunities, U.S.A. * International Journal of Management, IT and Engineering * http://www.ijmra.us * 431 * June * 2012 * (i) Mass of fuel consumed in all 3 cylinders = 0.00097984 Kg/s * (ii) Mass of fuel consumed in each cylinder = 0.0003266 Kg/s * (iii) Thermal efficiency = 20.46% * (iv) Specific fuel consumption = 0.39979 Kg/KW-hour * It can be noticed that as a result of integrating the working principles of EC and IC engines, * the following benefits are achieved: * (a) Maximum utilization of generated energy * (b) Decrease in overall fuel consumption * (c) Improvement in performance * The above mentioned benefits are supported by the following table of comparison: * Table 3: Comparative Conclusion * Parameters Engine Under Study * (Maruti 800, 796cc, * 3 cylinder inline) * Integrated Engine * (1 IC + 2 EC cylinders, * Inline, 800 cc) * Bore diameter 6.85cm for all * cylinders * IC cylinder = 8.85cm * EC cylinders = 5.62cm * (each) * Stroke length 7.2cm 7.2cm * Mechanical * efficiency 80% 80% * Brake Power * 8.823 KW at 2000 * rpm * 4.937 KW at 2000 rpm IJMIE Volume 2, Issue 6 ISSN: 2249-0558 * ___________________________________________________________ * A Monthly Double-Blind Peer Reviewed Refereed Open Access International e-Journal - Included in the International Serial Directories * Indexed & Listed at: Ulrich's Periodicals Directory ©, U.S.A., Open J-Gage as well as in Cabell’s Directories of Publishing Opportunities, U.S.A. * International Journal of Management, IT and Engineering * http://www.ijmra.us * 432 * June * 2012 * Mechanical * efficiency 80% 80% * Brake thermal * efficiency 20.46% 34.35% * Brake specific * fuel consumption 0.399789 Kg/KW-h 0.2381 Kg/KW-h * 4. Further Scope of Research * This concept of integration of the IC and EC approaches can be extended to different * applications such as * 1) Improving efficiency of vehicular Diesel engines * 2) Development of a compound Locomotive engine * 3) Introducing the concept of integration in Marine Engines * 4) Focusing on low manufacturing cost of integrated Engines * 5) Extending the concept to other engine configurations * 6) Upgrading Hybrid vehicles through this concept * 5. References * Books * [1] Internal Combustion Engine Fundamentals by John.B.Heywood, McGraw Hill Book * Company, New York * [2] Introduction to Internal Combustion Engine by Richard Stone, * [3] Design of Machine Elements by VB Bhandari 3rd Edition, Tata McGraw-Hill * [4] I.C Engines-Theory and Design by V.L. Maleev, McGraw Hill, New York IJMIE Volume 2, Issue 6 ISSN: 2249-0558 * ___________________________________________________________ * A Monthly Double-Blind Peer Reviewed Refereed Open Access International e-Journal - Included in the International Serial Directories * Indexed & Listed at: Ulrich's Periodicals Directory ©, U.S.A., Open J-Gage as well as in Cabell’s Directories of Publishing Opportunities, U.S.A. * International Journal of Management, IT and Engineering * http://www.ijmra.us * 433 * June * 2012 * [5] Engine Cooling Systems by Ray.T.Bohacz * [6] A Brief History of the Age of Steam: From the First Engine to the Boats and Railways by * Thomas Crump * [7] Watt's Perfect Engine: Steam and the Age of Invention by Ben Marsden, Columbia * University Press * [8] A Descriptive History of the Steam Engine by Robert Stuart. * Journals * [1] International Journal on Vehicle Design, Volume 45 - Issue 1/2 - 2007 * [2] Simulation of a Spark Ignited Engine, Transactions of the ASME, Journal of Internal * Combustion Engines, 94-ICE-17, Loper L.A. and S.R. Bell, 1994 * [3] Cycle Analysis for fuel-induced Internal Combustion Engine Configurations, Proceedings * of ImechE, Vol 215 of D, pp 115-125, Micklow G.J., B. Owens and M. Russels, 1994 * [4] Heat transfer characteristics of a spark ignition engine, Trans. A.S.M.E. J. Heat Transfer * 102,189-193 (1980), A.C. Alkidas * Websites * [1] www.scienceworld.wolfram.com/physics/OttoCycle.html * [2] www.sciencedirect.com/science/external_combustion_engine * [3] http://en.wikipedia.org/wiki/Internal_combustion_engine * [4] http://en.wikipedia.org/wiki/External_combustion_engine * [5] http://www.britannica.com/EBchecked/topic/290504/internal-combustion-engine * [6] http://www.freepatentsonline.com/4599863.html * [7] http://www.patentgenius.com/patent/4086771.html * [8] http://auto.howstuffworks.com/engine.htm * '''