DOCSLIB.ORG

Water Injection in the Modern Automotive Spark Ignition Engine

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Water Injection in the Modern Automotive Spark Ignition Engine Scholars' Mine Masters Theses Student Theses and Dissertations 1949 Water injection in the modern automotive spark ignition engine Leonard Carl Nelson Follow this and additional works at: https://scholarsmine.mst.edu/masters_theses Part of the Mechanical Engineering Commons Department: Recommended Citation Nelson, Leonard Carl, "Water injection in the modern automotive spark ignition engine" (1949). Masters Theses. 6801. https://scholarsmine.mst.edu/masters_theses/6801 This thesis is brought to you by Scholars' Mine, a service of the Missouri S&T Library and Learning Resources. This work is protected by U. S. Copyright Law. Unauthorized use including reproduction for redistribution requires the permission of the copyright holder. For more information, please contact [email protected]. i WATER INJECTION IN THE MODERN AUTOMOTIVE SPARK IGNITION ENGINE BY LEONARD C. NELSON A THESIS submitted to the faculty of the SCHOOL OF MINES AND METALLURGY OF THE UNIVERSITY OF MISSOURI in partial fulfillment of the work required for the Degree of MASTER OF SCIENCE, MElJHANICAL ENGINEERING MAJOR Rolla, Missouri 1949 1i ACKNONLEDGEMENTS The author is indebted to Dr. A. J. Miles for his guidance and timely suggestions during the course of this investigation, and t. the students who assisted in oonducting the tests. iii CONTENTS Page Acknowledgements ••••••••••••••••••••••• ii List of illustrations•••••••••••••••••• iT List of tables•••.••.•••••••••••••••••• T List of plates (graphs)•••••••••••••••• vi PART I Introduction•• ~ .••••••••••••••••••••••• 1 PART II Teat equipment .••.•••.••.•.••••.••••••• 6 PART III Test procedure••••••••••••••••••••••••• 9 PART IV Interpretation of test results••••••••• 14 PART V Conclusions •.•.••.••...•...•.....•..••. 42 Bibliography•••.••••••••••••••••••••••• 43 Vita............••.•......•..........•. 44 iT LIST OF ILLUSTRATIONS rig. Page 1. Photograph of test equipment••••••••••••••••••••••••••••• 12 2. Photograph of water injection system••••••••••••••••••••• 13 v LIST OF TABLES Table No. Page 1. Performance data for aviation gasoline••••••••••••••• 18 2. Performance data tor regular gasoline (J) •••••••••••• 20 3· Performance data for regular gasoline (A) •••..••••••• 22 4. Performance data for regular gasoline (B) •••••••••••• 24 5. Performance data for regular gasoline eC) •••••••••••• 26 6. Performance data for regular gasoline (D) •••••••••••• 28 1- Performance data tor regular gasoline (E) •••••••••••• 30 8. Performance data for regular gasoline (F) •••••••••••• 32 9- Performance data for regular gasoline eG) •••••••••••• 34 10. Performance data for regular gasoline (H) •••.•••••••• 36 11. Pertormance data for regular gasoline (I)•••...•.•.•• 38 12. Performance data tor regular gasoline (J)••...••••.•• 40 vi LIST OF PLATES Plate No. Page 1. Octane utilization•••••••••••••••••••••••••••••••••••• 11 2. Performance curves (87 octane gasoline)••••••••••••••• 19 3· Performance curves for regular gasoline (J) •••.••••••• 21 4. Performance curves for regular gasoline (A) ••••••••••• 23 5. Performance curves for regular gasoline (B) ••••••••••• 25 6. Performance curves for regular gasoline (C) ••••••••••• 27 7. Performance curves for regular gasoline (D) ••••••••••• 29 8. Performance curves for regular gasoline (E) ••••••••••• 31 9. Performanoe curves for regular gasoline (F) ••••••••••• 33 10. Performance curves for regular gasoline (G) ••..•..•..• 35' 11. Performance curves tor regular gasoline (H) ••••••••••• 31 12. Performance curves tor regular gasoline (I)••••••••••• 39 13. Performance curves for regular gasoline (J) ••••••.••.• 41 PART I INTRODUC TI ON 1 The injecti.on of water in the spark igniti.on engine is not new. The effect of humidity in the air on the performance of the spark ignition engine probably initiated the early investigations. The water vapor in the inlet air decreases the speed of the flame front and necessitates spark advance to assure maximum power and maximum efficiency. Water par­ ticles in the air evaporate during the compressi0n and combustion of the inducted charge and decrease the tendency of the engine to detonate. These effects are very evident when operating the spark ignition engine in a moist atmosphere. Water is not a foreign element to the internal combustion engine. It can be easily shown that when one pound of a hydrocarbon fuel burns more than one pound of water is formed in the combustion chamber. The average Hie molar ratio of all the hydrocarbons making up a gasoline is approximately 2.12. On the basis of complete combustion, the end pro­ ducts will be carbon dioxide and water. Balancing the chemical equation we have~ (l) Thus 1 mol of fuel forrr~ 1.06 mola of water. On a weight basis this is 1.125 pounds of water per pound of fuel. This combustion water and any injected water becomes superheated and passes out with the other exhaust products as a vapor. The fundamental reason for injecting water is to suppress ~onation. The exact nature as to how this is accomplished is not definitely known, but it is reasoned that the effect is due to the high heat of vaporization 2 of the water. Detonation, according to Ricardo,(l) results from auto- (1) H. R. Ricardo and H. S. Glyde, The High Speed Internal Combustion Engine, pp. 40-69. ignition of the last part of the charge to burn. Combustion originates normally at the electrodes of the spark plugs. The flame front of the burning progresses across the combustion chamber at rates varying from 40 to 100 it/sec. The rate is a function of these folloWing variables: fuel air ratio, initial pressure, initial temperature, residual gases, humidity, engine speed, compression ratio, and fuel composition. The high specific volume of the burned products tends to compress the mix- ture ahead of the flame front. As a result 'of the compression, the temperature of the unburned charge is raised. If the temperature of the unburned charge is raised above its self-ignition temperature, the entire unburned charge will spontaneously ignite. Once a fuel reaches its self-ignition temperature, a certain amount of time elapses before ignition takes place. The delay period is a function of the fuel com- position, fuel air ratio, and temperature. Although the fuel is above its self-ignition temperature, this delay period may allow the flame to pass through the unburned charge without detonation taking place. If the water acts only as a coolant, then water should affect all gasolines, with the same octane number, alike. When the water is inducted into the cylinder in a vapor state, it reduces the volumetric efficiency of the engine considerably. The specific volume or the vapor at 800r is 30,000 times as great as the specific vol- ume ot the liquid. If the water inducted is in the vapor state, it pro- vides no cooling, and hence no adTSntage can be claimed. The heat from 3 the charge necessary to vaporiz. the liquid water that is taken into the cylinder becomes unavailable since the temperature of the gases on the expansion stroke never drope below the condensation temperature of the water. The work from the superheated steam that forms from the heat exchange between the hot gases and the water caD not be equivalent to the work from the combustion products due to the irreversibility of the heat exchange process. With the aboTe in mind, it is evident that water or water vapor inducted into the engine will lower the output of the engine if the fuel air ratio, compression ratio, or spark advance re- mains the same. Detonation in a spark ignition engine can be controlled by varying the fuel air ratiG. At the beet power mixture the tendency to detonate is the greatest. MOst aircraft engines control detonation by increasing the fuel air ratio (rich mixture). Decreasing the fuel air ratio (lean mixture) would arrive at the same results with more economy but because a lean mixture burns slowly, the engine would tend to heat. To develop the War Emergency Power Rating established by the Army and Navy for the military aircraft without water injectioJl, it was necessary to enrich the mixture beyond "best power mixture" to supress detonatien. With water injectian the mixture could b. leaned t~ the "best power mixture," re- sulting in 8 gain over that power developed using the rieh mixture with­ out water injecti~n.(2) (2) Paul F. Adair, Low Octane Fuel Plus Water Equals High Engine Per­ formance, Aviation Maintenance, Vol. 1, pp. 43-45, February, 1944. Detonation can be controlled by reducing the compression ratio. 4 Lower compression ratios result in lower temperatures after compression, and also lower temperatures of the last part of the charge to burn. This in turn increases the ignition lag and allows normal combustion to take place. The equation for the efficiency of the theoretical spark ignition Otto engine is 1 N =1 - (2) r k _ 1 where r =compression ratio k =adiabatic coefficient It is evident that reducing the compression ratio cuts down on the .f- ficiency of the engine and the work output. Water injection will allow the use of the higher cODlpression ratio with a corresponding increase in efficiency. In the automobile engine today detonation is controlled to a great extent by spark timing. The compression ratio is considerably greater than that ratio which would allow the correct spark advance for maximum power using the regular fuels available. Hence, at full throttle the engine operates at a reduced spark. Water injection allows the spark to be advanced to the optimum position. Thus, more power, better economy, and cooler exhaust valves result. Mr. Wm. M. Holliday's tests(3) on a 1948 car with a compression ratio (3) Wm. U. Holliday, Progress Report on the Duel-Fuel System, S.A.E. Paper, June 6-11, 1948. of 7.0 to 1 shows that even under adverse conditione the engine could have been operating 80 per cent of the time knock-free with a 50 octane fuel. Hence, it is an economic waste to use high octane fuel during this 80 per cent of the time. Water injection is one of the answers to the solution of thi5 problem. Properly injected water could raise the octane number about 15 octane numbers (a solution of yater, alcohol and tetra- ethyl lead could raise the octane number as high 8S 34 octane numbers).
Load more

Recommended publications
  • Water/Methanol Injection: Frequently Asked Questions
    Water/Methanol Injection: Frequently Asked Questions Water/methanol injection is nothing new. It has been used as far back as World War II to help power German fighter planes. Yet it never seemed to catch on as a mainstream power adder in the hot rodding world—until recent years. Many companies are now offering easy to install water/methanol injections systems for affordable prices. Available for naturally aspirated or forced induction gasoline and diesel applications, these systems inject a roughly 50/50 mixture of methanol and water into the engine using a high-pressure pump. This magical mixture allows for more ignition timing, increases boost capability in supercharged or turbocharged applications, lowers air intake temperature, and provides an additional source of very high-octane fuel—all without increasing the chance of damaging detonation. Water injection systems are predominantly useful in forced induction (turbocharged or supercharged), internal combustion engines. Only in extreme cases such as very high compression ratios, very low octane fuel or too much ignition advance can it benefit a normally aspirated engine. The system has been around for a long time since it was already used in some World War II aircraft engines, which allowed them to produce more power and therefore fly at higher altitudes. A water injection system works similarly to a fuel injection system only it injects water instead of fuel. Water injection is not to be confused with water spraying on the intercooler's surface, water spraying is much less efficient and far less sophisticated. A turbocharger or supercharger essentially compresses the air going into the engine in order to force more air than would be possible with the atmospheric pressure.
    [Show full text]
  • Water Injection on Commercial Aircraft to Reduce Airport Nitrogen Oxides
    NASA/TM—2010-213179 Water Injection on Commercial Aircraft to Reduce Airport Nitrogen Oxides David L. Daggett and Lars Fucke Boeing Commercial Airplane, Seattle, Washington Robert C. Hendricks Glenn Research Center, Cleveland, Ohio David J.H. Eames Rolls-Royce Corporation, Indianapolis, Indiana March 2010 NASA STI Program . in Profile Since its founding, NASA has been dedicated to the • CONFERENCE PUBLICATION. Collected advancement of aeronautics and space science. The papers from scientific and technical NASA Scientific and Technical Information (STI) conferences, symposia, seminars, or other program plays a key part in helping NASA maintain meetings sponsored or cosponsored by NASA. this important role. • SPECIAL PUBLICATION. Scientific, The NASA STI Program operates under the auspices technical, or historical information from of the Agency Chief Information Officer. It collects, NASA programs, projects, and missions, often organizes, provides for archiving, and disseminates concerned with subjects having substantial NASA’s STI. The NASA STI program provides access public interest. to the NASA Aeronautics and Space Database and its public interface, the NASA Technical Reports • TECHNICAL TRANSLATION. English- Server, thus providing one of the largest collections language translations of foreign scientific and of aeronautical and space science STI in the world. technical material pertinent to NASA’s mission. Results are published in both non-NASA channels and by NASA in the NASA STI Report Series, which Specialized services also include creating custom includes the following report types: thesauri, building customized databases, organizing and publishing research results. TECHNICAL PUBLICATION. Reports of completed research or a major significant phase For more information about the NASA STI of research that present the results of NASA program, see the following: programs and include extensive data or theoretical analysis.
    [Show full text]
  • Reduction of NO Emissions in a Turbojet Combustor by Direct Water
    Reduction of NO emissions in a turbojet combustor by direct water/steam injection: numerical and experimental assessment Ernesto Benini, Sergio Pandolfo, Serena Zoppellari To cite this version: Ernesto Benini, Sergio Pandolfo, Serena Zoppellari. Reduction of NO emissions in a turbojet combus- tor by direct water/steam injection: numerical and experimental assessment. Applied Thermal Engi- neering, Elsevier, 2009, 29 (17-18), pp.3506. 10.1016/j.applthermaleng.2009.06.004. hal-00573476 HAL Id: hal-00573476 https://hal.archives-ouvertes.fr/hal-00573476 Submitted on 4 Mar 2011 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Accepted Manuscript Reduction of NO emissions in a turbojet combustor by direct water/steam in- jection: numerical and experimental assessment Ernesto Benini, Sergio Pandolfo, Serena Zoppellari PII: S1359-4311(09)00181-1 DOI: 10.1016/j.applthermaleng.2009.06.004 Reference: ATE 2830 To appear in: Applied Thermal Engineering Received Date: 10 November 2008 Accepted Date: 2 June 2009 Please cite this article as: E. Benini, S. Pandolfo, S. Zoppellari, Reduction of NO emissions in a turbojet combustor by direct water/steam injection: numerical and experimental assessment, Applied Thermal Engineering (2009), doi: 10.1016/j.applthermaleng.2009.06.004 This is a PDF file of an unedited manuscript that has been accepted for publication.
    [Show full text]
  • Direct Injection of Water Mist in an Intake Manifold Spark Ignition Engine
    International Journal of Automotive and Mechanical Engineering (IJAME) ISSN: 2229-8649 (Print); ISSN: 2180-1606 (Online); Volume 12, pp. 2809-2819, July-December 2015 ©Universiti Malaysia Pahang DOI: http://dx.doi.org/10.15282/ijame.12.2015.1.0236 Direct injection of water mist in an intake manifold spark ignition engine A.R. Babu1*, G. Amba Prasad Rao1 and T. Hari Prasad2 1Department of Mechanical Engineering, NIT, Warangal, 506004, India *Email: [email protected] Phone: +919581993346; Fax: +918572245126 2Department of Mechanical Engineering, SVEC, Tirupati, 5171024, India ABSTRACT The purpose of this study is to investigate the effects of water mist (WM) injected directly into an intake manifold spark ignition (SI) engine. WM flows through a nozzle at the throttle body of the four-cylinder four-stroke multi-point injection engine for testing the performance of exhaust emission system. The water is pumped in mist form into the intake manifold with an air-fuel mixture through the nozzle, which is located on the throttle body. Experimental work and simulation methods are combined by the presence and absence of WM addition, and the performance as well as emission produced by the engine is analyzed. The Gamma Technologies (GT) methods are used to simulate the model with and without WM addition. The experimental results indicate that the standard engine performance can be used to validate the simulation model. The engine measures include various parameters such as brake power, torque, volumetric efficiency, spark advance timing, and the concentration of CO and NOx with water and without water addition to the SI engine (i.e., the power, torque, volumetric efficiency of the engine is increased up to 10%).
    [Show full text]
  • Fuel Injection and Anti-Detonation
    Fuel Injection • These systems are similar to the Bendix/Stromberg pressure carburetors. • Air / fuel metering is accomplished by one device, fuel distribution occurs by intake distribution pipes. Unliscensed copyrighted material - W. North 1998 Fuel Injection • Manufacturers – Bendix – Contentintal Unliscensed copyrighted material - W. North 1998 Fuel Injection • Bendix • RS and RSA systems • Has four main sections – Air metering and regulation – fuel regulation – fuel metering – fuelUnliscensed distribution copyrighted material - W. North 1998 Fuel Injection • Uses the same A, B, C, D, pressures A = Impact air pressure B = Venturi air pressure C = Metered fuel pressure D = Fuel inlet pressure and Flow divider discharge pressure Unliscensed copyrighted material - W. North 1998 Fuel Injection • Air metering and regulation – accomplished by throttle plate and a throttle body assembly. – impact air and venturi air pressures are sourced here. – automatic mixture control valve regulates pressure value of impact air with venturi air. Unliscensed copyrighted material - W. North 1998 Fuel Injection • Fuel regulation – diaphragms and poppet valve attached to throttle assembly. – fuel inlet pressure closes poppet valve – metered fuel pressure and A - B pressure differential open poppet. Unliscensed copyrighted material - W. North 1998 Fuel Injection – balancing springs alter diaphragm values for low airflow idle conditions. – springs assist poppet valve to open for idle fuel delivery. – idle rotary valve is linked to throttle valve. Unliscensed copyrighted material - W. North 1998 Fuel Injection • Fuel metering section includes: – 74 micron finger screen – idle/enrichment fuel control rotary valve. – main and enrichment metering jets. – manual mixture and idle cut off rotary valve. Unliscensed copyrighted material - W. North 1998 Fuel Injection • Fuel distribution – metered fuel passes the poppet valve into plumbing to the flow divider where it forces open the pressurizing valve.
    [Show full text]
  • The Effect of Water-Injection on the Performance of Internal Combustion
    THE UNIVERSITY OF NEW SOUTH WALES BOX 1, POST OFFICE, KENSINGTON 26,8.66 WEISS, K. The Effect, of water-injection on the performance of internal combustion engines. Permission to read/ photocopy this thesis has been granted. Mechanical Eng THE EFFECT OF WATER-INJECT I ON ON THE PERFORMANCE OF INTERNAL COMBUSTION ENGINES by K. Weiss, Dipl.Ing. Vienna, A.M.I.E., Aust. A Higher Degree Thesis submitted to the N.S.W. University of Technology. June 1957. 0F NEW KEN5INGTDN a> j Ll BRA^ UNIVERSITY OF N.S.W. 27979 26. FEB.75 LIBRARY (i) SUMMARY To determine the influence of an anti-detonant injection on the performance of an internal combustion engine two methods were adopted: 1. A mathematical approach by which the theoretical drop of combustion temperature was calculated for an Otto cycle using octane as fuel and water as internal coolant, the water being 25% by weight of the fuel. The method derived holds good for any fuel and coolant. 2. An experimental method in which a series of engine tests were carried out using the Ricardo E-6/S variable compression engine with a manually controlled valve to regulate the coolant flow. The main object of this part of the thesis was to determine any improvement in power and economy, when water or water-alcohol at various weight-ratios was used for anti-detonant injections. Observation data, result sheets and performance curves are presented. The graphs are used to analyse test results but may also be used to calculate other values such as per- n ■- centage gain of power if desired*-;Econopy figures are based on 3s./8^/2d* per gal-ion for standard grade V petrol and 7s./Id.
    [Show full text]
  • Recycled Water Injection in a Turbocharged Gasoline Engine And
    Recycled Water Injection in a Turbocharged Gasoline Engine and Detailed Effects of Water on Auto-Ignition by Jeongyong Choi A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy (Mechanical Engineering) in the University of Michigan 2019 Doctoral Committee: Professor André L. Boehman, Co-Chair Associate Research Scientist John Hoard, Co-Chair Professor Venkat Raman Professor Angela Violi Jeongyong Choi [email protected] ORCID iD: 0000-0001-5144-1162 © Jeongyong Choi 2019 Acknowledgments First of all, I must thank to my wife and daughter, Veronica Son and Jia Choi for their support. They gave me constant love, happiness and encouragement during this long journey. I also would like to give my special thanks to my parents and parents-in-law for their endless love and support. I want to express my sincere gratitude to my research advisors, Prof. André Boehman and John Hoard. Because of their consistent research guidance, encouragement and financial support for last several years, I could finish my dissertation and got the faith in my abilities. Next my committee members, Prof. Angela Violi and Prof. Venkat Raman must be thanked for accepting to be on my committee and guiding me. My fellow lab mates, Kwang Hee Yoo and Taehoon Han must be acknowledged as they helped me a lot in better understanding of the experimental setup and the results. Also, I have worked with many undergraduate students and master students. I must thank to them for their great assistance. The financial support from Ford Motor Company as part of the Ford-UM alliance program is gratefully acknowledged.
    [Show full text]
  • The Impact of Water Injection on Spark Ignition Engine Performance Under High Load Operation
    Michigan Technological University Digital Commons @ Michigan Tech Dissertations, Master's Theses and Master's Reports 2017 THE IMPACT OF WATER INJECTION ON SPARK IGNITION ENGINE PERFORMANCE UNDER HIGH LOAD OPERATION Jeremy Worm Michigan Technological University, [email protected] Copyright 2017 Jeremy Worm Recommended Citation Worm, Jeremy, "THE IMPACT OF WATER INJECTION ON SPARK IGNITION ENGINE PERFORMANCE UNDER HIGH LOAD OPERATION", Open Access Dissertation, Michigan Technological University, 2017. https://digitalcommons.mtu.edu/etdr/552 Follow this and additional works at: https://digitalcommons.mtu.edu/etdr Part of the Energy Systems Commons, Heat Transfer, Combustion Commons, and the Other Mechanical Engineering Commons THE IMPACT OF WATER INJECTION ON SPARK IGNITION ENGINE PERFORMANCE UNDER HIGH LOAD OPERATION By Jeremy Worm A DISSERTATION Submitted in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY In Mechanical Engineering-Engineering Mechanics MICHIGAN TECHNOLOGICAL UNIVERSITY 2017 © 2017 Jeremy Worm This dissertation has been approved in partial fulfillment of the requirements for the Degree of DOCTOR OF PHILOSOPHY in Mechanical Engineering-Engineering Mechanics. Department of Mechanical Engineering – Engineering Mechanics Dissertation Advisor: Dr. Jeffrey D. Naber Committee Member: Dr. Darrell Robinette Committee Member: Dr. Jason Blough Committee Member: Dr. Scott Wagner Department Chair: Dr. William W. Predebon Dedication I dedicate this dissertation to my loving wife Jennifer. Without her unwavering
    [Show full text]
  • Frank Walker - “What Can I Do About This Problem?” by Kimble D
    Frank Walker - “What can I do about this problem?” By Kimble D. McCutcheon A lone Republic P-47 “Thunderbolt”, affectionately known as the “Jug” because of its rotund shape, was cruising in the bright sky of Germany. In one of the numerous skirmishes of the day, the Jug had become separated from its group. Now its pilot was headed home, low on ammunition and not exactly brimming with fuel. He had pulled the big Pratt & Whitney R-2800 back to less than half power and it was now sipping fuel at a rate of only 65 gallons per hour. To avoid any further enemy contact, he was flying at about 15,000 feet, in and out of the top of a broken overcast that hid him from the view of enemy fighters most of the time. The P-47 “Thunderbolt” Encountering one of the clear spots, the Jug pilot rapidly scanned above him and was shocked to see a couple of German Focke-Wulf Fw 190 fighters a few thousand feet above him and ahead by about a mile. “No threat”, he thought. Looking around still more, he now saw the object of the Fw 190’s interest – a lone B-17, trailing smoke from its number two engine, and heading for the cover of the same overcast the Jug pilot was using. It was evident to the Jug pilot that the B-17 could not make the other side of the clear area before the Fw 190s caught up. Knowing he had no time to spare, the Jug pilot flipped a switch on the top of his throttle and simultaneously pushed the propeller ,throttle and supercharger controls forward to the stops.
    [Show full text]
  • Effect of Methanol/Water Mixed Fuel Compound Injection on Engine Combustion and Emissions
    energies Article Effect of Methanol/Water Mixed Fuel Compound Injection on Engine Combustion and Emissions Changchun Xu and Haengmuk Cho * Division of Mechanical and Automotive Engineering, Kongju National University 275, Budae-dong, Cheonan-si 331-717, Chungcheongnam-do, Korea; [email protected] * Correspondence: [email protected] Abstract: Due to the recent global increase in fuel prices, to reduce emissions from ground transporta- tion and improve urban air quality, it is necessary to improve fuel efficiency and reduce emissions. Water, methanol, and a mixture of the two were added at the pre-intercooler position to keep the same charge and cooling of the original rich mixture, reduce BSFC and increase ITE, and promote combustion. The methanol/water mixing volume ratios of different fuel injection strategies were compared to find the best balance between fuel consumption, performance, and emission trends. By simulating the combustion mechanism of methanol, water, and diesel mixed through the Chemkin system, the ignition delay, temperature change, and the generation rate of the hydroxyl group (−OH) in the reaction process were analyzed. Furthermore, the performance and emission of the engine were analyzed in combination with the actual experiment process. This paper studied the application of different concentration ratios of the water–methanol–diesel mixture in engines. Five concentration ratios of water–methanol blending were injected into the engine at different injection ratios at the pre-intercooler position, such as 100% methanol, 90% methanol/10% water, 60% methanol/40% water, 30% methanol/70% water, 100% water was used. With different volume ratios of premixes, the combustion rate and combustion efficiency were affected by droplet extinguishment, flashing, Citation: Xu, C.; Cho, H.
    [Show full text]
  • (MIPCC) Is a Promising Technolog
    Note by Joe Sylvia: This was the Final Submission to hopefully win the Contract. Identification and Significance of Problem or Opportunity Mass Injection Pre-Compressor Cooling (MIPCC) is a promising technology that can permit conventional jet engines, normally limited in speed and altitude, to propel aircraft to substantially higher altitudes and velocities. By injecting coolant ahead of the compressor and using its heat of vaporization to cool inlet gasses, the engine can operate at substantially higher velocities without exceeding temperature limits. An additional feature of this process is a significant increase in thrust that can be used for added acceleration or climb to higher altitudes. Because the concept depends on a relatively simple kit modification of existing jet engines, it can be fielded near term without need for extended engine development. It can be used either to augment the performance of existing aircraft, or to propel a new generation of high performance aircraft that can benefit from rapid climb and acceleration performance as well as the high efficiency cruise normally associated with conventional jet aircraft. To explore this technology opportunity a number of organizations have independently entered into Phase-I research programs designed to build an analytical foundation for the technology as well as conduct limited proof of concept hardware demonstrations. Through the course of their Phase-1 efforts several organizations have developed a relationship of cooperation that has lead to this combined proposal for continued Phase II study. This Phase II effort is led by HMX, Inc., in a teaming arrangement with MSE-Technologies, Inc. and Spath Engineering. This team proposes to take the next step in development by pursuing a full-scale hardware demonstration under representative flight conditions using a high performance engine.
    [Show full text]
  • A Numerical Investigation on the Potentials of Water Injection to Increase Knock Resistance and Reduce Fuel Consumption in Highly Downsized GDI Engines
    Available online at www.sciencedirect.com ScienceDirect Energy Procedia 81 ( 2015 ) 826 – 835 69th Conference of the Italian Thermal Engineering Association, ATI 2014 A numerical investigation on the potentials of water injection to increase knock resistance and reduce fuel consumption in highly downsized GDI engines Fabio Bernia*, Sebastiano Bredaa, Mattia Luglia, Giuseppe Cantorea† aDepartment of Engineering “Enzo Ferrari”, University of Modena and Reggio Emilia, Modena, Italy Abstract 3D CFD analyses are used to analyse the effects of port-injection of water in a high performance turbocharged GDI engine. Particularly, water injection is adopted to replace mixture enrichment while preserving, if not improving, indicated mean effective pressure and knock resistance. A full-load / maximum power engine operation of a currently made turbocharged GDI engine is investigated comparing the actual adopted fuel-only rich mixture to stoichiometric-to-lean mixtures, for which water is added in the intake port under constant charge cooling in the combustion chamber. In order to find the optimum fuel/water balance, preliminary analyses are carried out using a chemical reactor to evaluate the effects of charge dilution and mixture modification on both autoignition delays and laminar flame speeds. Thanks to the lower chemical reactivity of the diluted end gases, the water-injected engine allows the spark advance (SA) to be increased; as a consequence, engine power target is met, or even crossed, with a simultaneous relevant reduction of fuel consumption. ©© 20152015 PublishedThe Authors. by ElsevierPublished Ltd. by ThisElsevier is an Ltd. open access article under the CC BY-NC-ND license (Peer-reviewhttp://creativecommons.org/licenses/by-nc-nd/4.0/ under responsibility of the Scientific Committee).
    [Show full text]