DOCSLIB.ORG

US5507253.Pdf

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
US5507253.Pdf |||||||||| USO05507253A United States Patent (19) 11 Patent Number: 5,507,253 Lowi, Jr. (45) Date of Patent: Apr. 16, 1996 54 ADABATIC, TWO-STROKECYCLE ENGINE ing,” SAE Paper 650007. HAVING PSTON-PHASING AND John C. Basiletti and Edward F. Blackburne, Dec. 1966, COMPRESSION RATO CONTROL SYSTEM "Recent Developments in Variable Compression Ratio Engines.” SAE Paper 660344. 76 Inventor: Alvin Lowi, Jr., 2146 Toscanini Dr., L. J. K. Setright, "Some Unusual Engines,” Dec. 1975, pp. Rancho Palos Verde, Calif. 90732 99-105, 109-111. R. Kamo, W. Bryzik and P. Glance Dec. 1987, "Adiabatic (21) Appl. No.: 311,348 Engine Trends-Worldwide,” SAE Paper 870018. (22 Filed: Sep. 23, 1994 S. G. Timony, M. H. Farmer and D. A. Parker, Dec. 1987, "Preliminary Experiences with a Ceramics Evaluation Related U.S. Application Data Engine Rig.” SAE Paper 870021. Paul and Humphrheys, Dec. 1952, SAE Transactions No. 6, 63 Continuation of Ser. No. 112,887, Aug. 27, 1993, Pat. No. 5,375,567. p. 259. (51) Int. Cl." ......................................... FO2B 75/26 Primary Examiner-Marguerite Macy I52 U.S. Cl. .................................... 123/S6.9 Attorney, Agent, or Firm-Bruce M. Canter 58) Field of Search .................................. 123/55.7, 56.1, 123/56.2, 56.8, 56.9, 51 B, 193.6 57) ABSTRACT An engine structure and mechanism that operates on various 56) References Cited combustion processes in a two-stroke-cycle without supple U.S. PATENT DOCUMENTS mental cooling or lubrication comprises an axial assembly of cylindrical modules and twin, double-harmonic cams that 1,127,267 2/1915 McElwain .............................. 123/56.8 operate with opposed pistons in each cylinder through fully 1,339,276 5/1920 Murphy .................................. 123/56.8 captured rolling contact bearings. The opposed pistons are 1,808,083 6/1931 Tibbetts .................................. 123/56.9 2,076,334 4/1937 Burns ..................................... 123/56.9 double-acting, performing a two-stroke engine power cycle 2,243,817 5/1941 Herrmann. on facing ends and induction and scavenge air compression 2,243,818 5/1941 Herrmann ............................... 123/173 on their outside ends, all within the same cylinderbore. The 2,243,819 5/1941 Herrmann ... ... 23/196 engine includes a control system which utilizes twin barrel 2,243,820 5/1941 Herrmann ... ... 123/56 cams with adjustable axial and angular positions enabling 4,791,787 12/1988 Paul et al............................... 60/605.1 independent compression ratio and port phasing variation 4,856.463 8/1989 Johnston ..... 123/51 BA during operation. The engine control system comprises one 4,996,953 3/1991 Buck ...................................... 123/56.9 or more electrohydraulic servos to set and maintain the axial 5,058,536 10/1991 Johnston . ... 123151 BA and angular relationships of the cams either at extreme 5,215,045 6/1993 Vadnjal .................................. 123/56.8 positions or controlled to particular positions and schedules OTHER PUBLICATIONS thereof utilizing instantaneous piston position feedback information. P. M. Heldt Dec. 1943, "High Speed Diesel Engines,” Fourth Ed., pp. 308-311, 320-327. S. G. Timony, Dec. 1965, "Diesel Design for Turbocharg 16 Claims, 13 Drawing Sheets 2 16 52 50 - 44 14 2.2 2 34 22 liv42 32 2 300 zircreen rear frees ÉY freeler-- 2M AAAAAA CANARY ARAS A SAN FAAAAAAAA 2 a 1 2skerry's sixx rear are extraorra 2M 3O 34 49 f8 52 52 f4 50 " 46 32 2 U.S. Patent Apr. 16, 1996 Sheet 1 of 13 5,507,253 297 2€. 22° þ/ 9/2.*L2.Nos U.S. Patent Apr. 16, 1996 Sheet 2 of 13 5,507,253 U.S. Patent Apr. 16, 1996 Sheet 3 of 13 5,507,253 U.S. Patent Apr. 16, 1996 Sheet 4 of 13 5,507,253 As PISION RECIPROCATION PHASE TOC BDC TDC BDC SHAFTAAGLE O 90 /30 27() U.S. Patent Apr. 16, 1996 Sheet 5 of 13 5,507,253 24 2.2 23 HZ --- x%2D42 4 (2% 22 as Ly: E U.S. Patent Apr. 16, 1996 Sheet 7 of 13 5,507,253 S N S S S\ E N 242 VO N nN F Q) N 37 3. zé Z2 S. 24 24 YZ YS C (N N NNN & T NS His NY,NNZ Z U.S. Patent Apr. 16, 1996 Sheet 9 of 13 5,507,253 76 ) 94 6O U.S. Patent Apr. 16, 1996 sheet 10 of 13 5,507,253 S. ON N & S. r N s s (NN SS Sn ( N 1 QN Q N sk. N. Q St. SS N SJ N-- nS NS S S S.A & Q & SS SS R U.S. Patent Apr. 16, 1996 Sheet 11 of 13 5,507,253 154 U.S. Patent Apr. 16, 1996 Sheet 12 of 13 5,507,253 U.S. Patent Apr. 16, 1996 Sheet 13 of 13 5,507,253 VHSH–/vol_1/SQ/132/3767627/V7 // -677 5,507,253 1 2 ADLABATIC, TWO-STROKECYCLE ENGINE lubrication schemes to maintain their mechanical and struc HAVING PSTON-PHASING AND tural integrity and their weight and balance is highly sensi COMPRESSION RATO CONTROL SYSTEM tive to increases in cylinder working pressures and rotational speeds. Thus, prior art engines that operate on the diesel cycle are somewhat heavier and larger than their spark RELATED CASES ignition counterparts and they also present greater lubrica tion, cooling and balancing burdens. This accounts, to a This application is a continuation of U.S. application Ser. large extent, for the lack of acceptance, heretofore, of prior No. 08/112,887, filed on Aug. 27, 1993, now U.S. Pat. No. art type diesel engines for aircraft applications notwithstand 5,375,367, and incorporated by reference as if fully set forth ing their potentially superior flight-worthiness, safety, fuel herein. O economy and fuel flexibility characteristics. Various attempts have heretofore been made to overcome FIELD OF INVENTION some of these problems by designing diesel engines with large heat retention capacities. Examples of such "adiabatic This invention relates to uncooled, two-stroke-cycle, engine' are those manufactured by Adiabatic Inc. and Cum opposed-piston, uniflow-scavenging internal combustion 15 mins. These adiabatic engines utilize insulated parts, heat engines, and to piston phasing and compression ratio con tolerant components and high-temperature tribology or fric trols for such engines. Specifically, the engine relates to an tion controls. However, such friction controls require axial-cylinder, twin-barrel-cam engine, wherein the control advanced chemistry for liquid lubrication. What is needed is system provides independently controllable compression an adiabatic engine that overcomes these shortcomings. ratio and port timing, offering improved power density, 20 With rare exceptions, prior art reciprocating engines, efficiency, smoothness, compactness, torque and thermal adiabatic or otherwise, utilize crankshafts and connecting tolerance. The engine system herein has particular value in rods for the translation of reciprocating to rotary motion. aviation propulsion and other engine power applications This arrangement has been successfully applied to engines demanding maximum performance over wide load, speed comprised of from one to many cylinders laid out in various and altitude range. 25 configurations such as in a single line of cylinders parallel to BACKGROUND - DESCRIPTION OF PRIOR the crankshaft, banks of inline cylinders disposed around the ART crankshaft, radial cylinder dispositions and opposed-piston arrangements using one or more crankshafts geared together. Heretofore, internal combustion engines of the recipro A few crankshaft-type engines are known which have been cating type have been constructed of metals in forms best 30 constructed with parallel cylinders axially aligned in a barrel suited for their fabrication in such materials. However, due arrangement around the crankshaft or with inline cylinders to these materials prior art engines require supplemental transverse to the crankshaft. Both of these types rely on cooling and lubrication in order to function properly with additional auxiliary mechanisms such as gear trains, rocker adequate durability. These cooling and lubrication require arms, wobble plates, universal ball joints and the like for the ments further require provisions for fluid circulation and 35 translation of power. heat rejection accessories that can be burdensome in many Prior art engines that utilize crankshafts provide no applications. Aircraft applications of such engines are par mechanical advantage in the conversion of piston motion to ticularly sensitive to the installation of such accessories shaft torque. Furthermore, eccentricities in connecting rods because of the weight and aerodynamic drag associated with 40 and the like produce side loads in the reciprocating pistons their proper usage. In addition, the control of fluids in which give rise to friction and vibration. Another disadvan aircraft engines and their remote accessories such as radia tage of crankshaft-type engines is the complex load path that tors, oil coolers, pumps, oil sumps and the like is compli must be structurally accommodated in maintaining the cated because a fixed gravitational orientation can not be mechanical integrity of the engine. Typically, such loads are relied upon to disengage vapors and liquids and establish 45 passed through the cylinder walls which must also handle fluid levels. the stresses due to combustion. As a result, the cylinders A further disadvantage of most prior art engine construc must be constructed of materials having high tensile tions for aircraft applications is their dependence on strengths. Due to the complex forms of the structures increased output shaft speed as a means of reducing weight required, metallic materials constitute the only economic per unit of power output. Because propellers function effi 50 and durable means of construction, and then only if an ciently only with limited rotational speeds, most light abundance of cooling and lubrication is used. Furthermore, weight engines of the prior art type require speed-reducing crankshafts, by nature, must span the length of the engine.
Load more

Recommended publications
  • Los Motores Aeroespaciales, A-Z
    Sponsored by L’Aeroteca - BARCELONA ISBN 978-84-608-7523-9 < aeroteca.com > Depósito Legal B 9066-2016 Título: Los Motores Aeroespaciales A-Z. © Parte/Vers: 1/12 Página: 1 Autor: Ricardo Miguel Vidal Edición 2018-V12 = Rev. 01 Los Motores Aeroespaciales, A-Z (The Aerospace En- gines, A-Z) Versión 12 2018 por Ricardo Miguel Vidal * * * -MOTOR: Máquina que transforma en movimiento la energía que recibe. (sea química, eléctrica, vapor...) Sponsored by L’Aeroteca - BARCELONA ISBN 978-84-608-7523-9 Este facsímil es < aeroteca.com > Depósito Legal B 9066-2016 ORIGINAL si la Título: Los Motores Aeroespaciales A-Z. © página anterior tiene Parte/Vers: 1/12 Página: 2 el sello con tinta Autor: Ricardo Miguel Vidal VERDE Edición: 2018-V12 = Rev. 01 Presentación de la edición 2018-V12 (Incluye todas las anteriores versiones y sus Apéndices) La edición 2003 era una publicación en partes que se archiva en Binders por el propio lector (2,3,4 anillas, etc), anchos o estrechos y del color que desease durante el acopio parcial de la edición. Se entregaba por grupos de hojas impresas a una cara (edición 2003), a incluir en los Binders (archivadores). Cada hoja era sustituíble en el futuro si aparecía una nueva misma hoja ampliada o corregida. Este sistema de anillas admitia nuevas páginas con información adicional. Una hoja con adhesivos para portada y lomo identifi caba cada volumen provisional. Las tapas defi nitivas fueron metálicas, y se entregaraban con el 4 º volumen. O con la publicación completa desde el año 2005 en adelante. -Las Publicaciones -parcial y completa- están protegidas legalmente y mediante un sello de tinta especial color VERDE se identifi can los originales.
    [Show full text]
  • Principles of an Internal Combustion Engine
    Principles of an Internal Combustion Engine Course No: M03-046 Credit: 3 PDH Elie Tawil, P.E., LEED AP Continuing Education and Development, Inc. 22 Stonewall Court Woodcliff Lake, NJ 076 77 P: (877) 322-5800 [email protected] Chapter 2 Principles of an Internal Combustion Engine Topics 1.0.0 Internal Combustion Engine 2.0.0 Engines Classification 3.0.0 Engine Measurements and Performance Overview As a Construction Mechanic (CM), you are concerned with conducting various adjustments to vehicles and equipment, repairing and replacing their worn out broken parts, and ensuring that they are serviced properly and inspected regularly. To perform these duties competently, you must fully understand the operation and function of the various components of an internal combustion engine. This makes your job of diagnosing and correcting troubles much easier, which in turn saves time, effort, and money. This chapter discusses the theory and operation of an internal combustion engine and the various terms associated with them. Objectives When you have completed this chapter, you will be able to do the following: 1. Understand the principles of operation, the different classifications, and the measurements and performance standards of an internal combustion engine. 2. Identify the series of events, as they occur, in a gasoline engine. 3. Identify the series of events, as they occur in a diesel engine. 4. Understand the differences between a four-stroke cycle engine and a two-stroke cycle engine. 5. Recognize the differences in the types, cylinder arrangements, and valve arrangements of internal combustion engines. 6. Identify the terms, engine measurements, and performance standards of an internal combustion engine.
    [Show full text]
  • Mathematical Modeling and Analysis of Gas Torque in Twinrotor Piston
    J. Cent. South Univ. (2013) 20: 3536−3544 DOI: 10.1007/s11771­013­1879­y Mathematical modeling and analysis of gas torque in twin­rotor piston engine DENG Hao(邓豪) 1, 2, PAN Cun­yun(潘存云) 1, XU Xiao­jun(徐小军) 1, ZHANG Xiang(张湘) 1 1. College of Mechatronic Engineering and Automation, National University of Defense Technology, Changsha 410073, China; 2. Naval Aeronautical Engineering Institute, Qingdao Branch, Qingdao 266041, China © Central South University Press and Springer­Verlag Berlin Heidelberg 2013 Abstract: The gas torque in a twin­rotor piston engine (TRPE) was modeled using adiabatic approximation with instantaneous combustion. The first prototype of TRPE was manufactured. This prototype is intended for high power density engines and can produce 36 power strokes per shaft revolution. Compared with the conventional engines, the vector sum of combustion gas forces acting on each rotor piston in TRPE is a pure torque, and the combustion gas rotates the rotors while compresses the gas in the compression chamber at the same time. Mathematical modeling of gas force transmission was built. Expression for gas torque on each rotor was derived. Different variation patterns of the volume change of working chamber were introduced. The analytical and numerical results is presented to demonstrate the main characteristics of gas torque. The results show that the value of gas torque in TRPE falls to be less than zero before the combustion phase is finished; the time for one stroke is 30° in terms of the rotating angle of the output shaft; gas torque in one complete revolution of the output shaft has a period which is equal to 60° and it is necessary to put off the moment when gas torque becomes zero in order to export the maximum energy.
    [Show full text]
  • ENRESO WORLD - Ilab
    ENRESO WORLD - ILab Different Car Engine Types Istas René Graduated in Automotive Technologies 1-1-2019 1 4 - STROKE ENGINE A four-stroke (also four-cycle) engine is an internal combustion (IC) engine in which the piston completes four separate strokes while turning the crankshaft. A stroke refers to the full travel of the piston along the cylinder, in either direction. The four separate strokes are termed: 1. Intake: Also known as induction or suction. This stroke of the piston begins at top dead center (T.D.C.) and ends at bottom dead center (B.D.C.). In this stroke the intake valve must be in the open position while the piston pulls an air-fuel mixture into the cylinder by producing vacuum pressure into the cylinder through its downward motion. The piston is moving down as air is being sucked in by the downward motion against the piston. 2. Compression: This stroke begins at B.D.C, or just at the end of the suction stroke, and ends at T.D.C. In this stroke the piston compresses the air-fuel mixture in preparation for ignition during the power stroke (below). Both the intake and exhaust valves are closed during this stage. 3. Combustion: Also known as power or ignition. This is the start of the second revolution of the four stroke cycle. At this point the crankshaft has completed a full 360 degree revolution. While the piston is at T.D.C. (the end of the compression stroke) the compressed air-fuel mixture is ignited by a spark plug (in a gasoline engine) or by heat generated by high compression (diesel engines), forcefully returning the piston to B.D.C.
    [Show full text]
  • Aircraft Propulsion C Fayette Taylor
    SMITHSONIAN ANNALS OF FLIGHT AIRCRAFT PROPULSION C FAYETTE TAYLOR %L~^» ^ 0 *.». "itfnm^t.P *7 "•SI if' 9 #s$j?M | _•*• *• r " 12 H' .—• K- ZZZT "^ '! « 1 OOKfc —•II • • ~ Ifrfil K. • ««• ••arTT ' ,^IfimmP\ IS T A Review of the Evolution of Aircraft Piston Engines Volume 1, Number 4 (End of Volume) NATIONAL AIR AND SPACE MUSEUM 0/\ SMITHSONIAN INSTITUTION SMITHSONIAN INSTITUTION NATIONAL AIR AND SPACE MUSEUM SMITHSONIAN ANNALS OF FLIGHT VOLUME 1 . NUMBER 4 . (END OF VOLUME) AIRCRAFT PROPULSION A Review of the Evolution 0£ Aircraft Piston Engines C. FAYETTE TAYLOR Professor of Automotive Engineering Emeritus Massachusetts Institute of Technology SMITHSONIAN INSTITUTION PRESS CITY OF WASHINGTON • 1971 Smithsonian Annals of Flight Numbers 1-4 constitute volume one of Smithsonian Annals of Flight. Subsequent numbers will not bear a volume designation, which has been dropped. The following earlier numbers of Smithsonian Annals of Flight are available from the Superintendent of Documents as indicated below: 1. The First Nonstop Coast-to-Coast Flight and the Historic T-2 Airplane, by Louis S. Casey, 1964. 90 pages, 43 figures, appendix, bibliography. Price 60ff. 2. The First Airplane Diesel Engine: Packard Model DR-980 of 1928, by Robert B. Meyer. 1964. 48 pages, 37 figures, appendix, bibliography. Price 60^. 3. The Liberty Engine 1918-1942, by Philip S. Dickey. 1968. 110 pages, 20 figures, appendix, bibliography. Price 75jf. The following numbers are in press: 5. The Wright Brothers Engines and Their Design, by Leonard S. Hobbs. 6. Langley's Aero Engine of 1903, by Robert B. Meyer. 7. The Curtiss D-12 Aero Engine, by Hugo Byttebier.
    [Show full text]
  • Engine Modeling of an Internal Combustion Engine
    Engine Modeling of an Internal Combustion Engine With Twin Independent Cam Phasing THESIS Presented in Partial Fulfillment of the Requirements for Graduation with Distinction at The Ohio State University By Jason Meyer * * * * * The Ohio State University 2007 Defense Committee: Approved by Professor Yann Guezennec, Advisor Professor James Schmiedeler Adviser Undergraduate Program in Mechanical Engineering Copyright Jason Meyer 2007 Table of Contents Table of Contents .............................................................................................................. 1 Table of Figures................................................................................................................. 3 Acknowledgements ........................................................................................................... 5 Abstract.............................................................................................................................. 6 Chapter 1: Introduction ................................................................................................... 7 Chapter 2: Literature Review.......................................................................................... 9 2.1. Variable Valve Actuation Introduction ............................................................... 9 2.2 Types of Variable Valve Actuation ..................................................................... 12 2.2.1 Discretely-Stage Cam Systems...................................................................... 12 2.2.2
    [Show full text]
  • FAILURE Engine Analysis Booklet
    FAILURE Engine Analysis Booklet © 2013 ECHO Incorporated – 400 Oakwood Road. Lake Zurich, IL 60047-1564 INTRODUCTION The best way to analyze an engine failure is by investigating what caused the fail- ure. This is very similar to a detective looking for evidence at a crime scene. It’s important not just to look at engine damage. Instead, look for clues outside the engine, test some components and then pull the cylinder to look for more clues inside the engine. The most accurate cause of an engine failure can be determined once all the available facts are assembled. Table of Contents INTRODUCTION .....................................................................2 2-STROKE ENGINE FUNDAMENTALS ..........................................3 ENGINE FAILURE BASICS ........................................................4 SPECIAL TOOLS ....................................................................8 SERVICE INFORMATION ..........................................................9 OUTSIDE ENGINE CHECKS & TESTS ........................................ 10 INSIDE ENGINE CHECKS ........................................................ 16 RAW GAS FAILURES ............................................................ 19 DIRT INGESTION FAILURES ...................................................20 LEAN SEIZE FAILURES ..........................................................22 OVERHEATING FAILURES ......................................................24 DETONATION / PRE-IGNITION .................................................27 STALE FUEL FAILURES
    [Show full text]
  • A Review of Variable Valve Timing Devices Paul Shelton University of Arkansas, Fayetteville
    View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by ScholarWorks@UARK University of Arkansas, Fayetteville ScholarWorks@UARK Mechanical Engineering Undergraduate Honors Mechanical Engineering Theses 5-2008 A Review of Variable Valve Timing Devices Paul Shelton University of Arkansas, Fayetteville Follow this and additional works at: http://scholarworks.uark.edu/meeguht Part of the Applied Mechanics Commons, Electrical and Electronics Commons, and the Electro- Mechanical Systems Commons Recommended Citation Shelton, Paul, "A Review of Variable Valve Timing Devices" (2008). Mechanical Engineering Undergraduate Honors Theses. 17. http://scholarworks.uark.edu/meeguht/17 This Thesis is brought to you for free and open access by the Mechanical Engineering at ScholarWorks@UARK. It has been accepted for inclusion in Mechanical Engineering Undergraduate Honors Theses by an authorized administrator of ScholarWorks@UARK. For more information, please contact [email protected]. A REVIEW OF VARIABLE VALVE TIMING DEVICES A thesis submitted in partial fulfillment of the requirements for the Honors Program, for the degree of Bachelor of Science in Mechanical Engineering by P. Blair Shelton, Mechanical Engineering Thesis Advisor – Dr. Larry Roe Dr. Adam Huang May 2008 University of Arkansas 2 Acknowledgements I would like to thank Dr. Roe and Huang for their continued support and guidance of my automotive research, Vanessa for bringing me food on those long nights of research, Aaron for helping with the formatting
    [Show full text]
  • A Space Cam Mechanism for Power Transmission of an Opposite
    MATEC Web of Conferences 22, 03003 (2015) DOI: 10.1051/matecconf/2015220300 3 C Owned by the authors, published by EDP Sciences, 2015 A Space Cam Mechanism for Power Transmission of an Oppo- site-cylinder Piston Engine Haoyue Zhang*, Xiaojun Xu, Lei Zhang, Faliang Zhou College of Mechatronics Engineering and Automation, National University of Defense Technology, Changsha, Hunan, China ABSTRACT: For the purpose of improving the engine’s power density, we put forward a new type of power transmission mechanism which is used for opposed-cylinder engine. The gas pressure acts on the cam through the piston and push rod, and the spindle rotation of external is driven by the cam. The design of spatial cam work surface is completed by using the enveloping theory of a family of space curves, the force between roller and cam is analyzed using dynamic analysis software. Under the condition of equal number, size and stroke of piston, the new one with larger power density is more compact in structure than the traditional power transmission mechanism, and the reaction force on either side of the main shaft and the acting force between pistons and cyl- inders are smaller than those in traditional one, which prolongs the service life of the pistons. Keywords: power transmission; space cam; supercharge; stress 1 INTRODUCTION 2 THE COMPOSITION AND THE PRESSURIZA- TION THEORY OF NOVEL POWER TRANS- The special space mechanism internal combustion MISSION MECHANISM engine has been widely applied in military fields, and familiar ones are cam-type, swash plate-type and New power transmission mechanism transforms the wobble plate-type (Peng et al.
    [Show full text]
  • Master's Thesis
    Potential Future Engine Cycles for Improved Thermal Efficiency Analysis of Various Internal Waste Heat Recovery Cycles with Minimal Deviation From Common Engine Architectures MICHAEL J. DENNY Department of Applied Mechanics Combustion Division Chalmers University of Technology Gothenburg, Sweden 2014 Master's Thesis 2014:32 Potential Future Engine Cycles for Improved Thermal Efficiency Analysis of Various Internal Waste Heat Recovery Cycles with Minimal Deviation From Common Engine Architectures MICHAEL J. DENNY © MICHAEL J. DENNY, 2014 Master's Thesis 2014:32 ISSN 1652-8557 Department of Applied Mechanics Combustion Division Chalmers University of Technology SE-412 96 G¨oteborg Sweden Telephone: + 46 (0)31-772 1000 Thesis performed at: Volvo Car Corporation Advanced Engine Engineering Dept. 97624 PO Box PV4B SE-405 31 G¨oteborg Sweden Printed by: Chalmers Reposervice G¨oteborg, Sweden 2014 Abstract A comparative 1-D analysis is undertaken between a baseline internal combustion engine (ICE) and several ICE operating cycle concepts which are intended to produce higher brake efficiencies than the baseline which runs on an Otto cycle. The baseline is a spark ignition gasoline engine representative of modern naturally aspirated automotive engines in its architecture and implemented technologies. Engine models are created and compared in the 1-D engine simulation software program GT-Power created by Gamma Technologies. After calibrating the performance of each model with the same resolution and tuning strategies, the result is that all of the concepts are less efficient than the base- line engine. Each engine concept requires additional hardware to separate the processes of the cycle within the engine. These components add to the mechanical friction, flow, and heat losses within the engine, and in some cases manage only to transfer exergy into different forms, not reduce it in a positive way.
    [Show full text]
  • Rotary Combustion Engine
    ROTARY COMBUSTION ENGINE This article is about internal combustion engines that do not use conventional pistons. See also rotary engine for the World War I aircraft engines by that name. A rotary engine is an internal combustion engine that does not use pistons in the way a reciprocating enginedoes, but instead uses one or more rotors, sometimes called rotary pistons. Further clarification The term rotary combustion engine has been suggested as an alternative name for these engines to distinguish them from the obsolete aircraft engines also known as rotary engines. However both continue to be called rotary engines and only the context determines which type is meant. In particular, the only commercial producer of (pistonless) rotary engines as of 2005, Mazda, consistently refers to their Wankel engines asrotary engines. The basic concept of a (pistonless) rotary engine is to avoid the reciprocating motion of the piston with its inherent vibration and rotational-speed-related mechanical stress. As of 2005 the Wankel engine is the only successful pistonless rotary engine, but many similar concepts have been proposed and are under various stages of development. There are countless other examples of rotary engines varying in rotor design, size and many other categories. Notable examples include: The quasiturbine. The Sarich orbital engine. A rotary engine developed by Texas machinist Frank Turner which was licensed by Malcolm Bricklin for use in place of the V8 powering the Bricklin SV- 1 vehicle, but never used. The Rand Cam engine Advantages All such engines have the potential to improve on the piston engine in the areas of: Higher power-to-weight ratios.
    [Show full text]
  • CAM TERMINOLOGY ABDC: After Bottom Dead Center
    The following information is provided to help you understand some of the terminology related to camshaft specifications, and information. 1. Max Lift or Nose 2. Flank 3. Opening Clearance Ramp 4. Closing Clearance Ramp 5. Base Circle 6. Exhaust Opening Timing Figure 7. Exhaust Closing Timing Figure 8. Intake Opening Timing Figure 9. Intake Closing Timing Figure 10. Lobe Separation CAM TERMINOLOGY ABDC: After Bottom Dead Center. Measured in degrees. ASYMMETRICAL: Not identical on both sides of the lobe. In most cases, the opening side of the lobe being much more aggressive than the closing side. This difference is only visible in some overhead cams. ATDC: After Top Dead Center. Measured in degrees. BASE CIRCLE: The concentric or round portion of the cam lobe where the valve lash adjustments are made. A high spot in this area is called BASE CIRCLE RUNOUT. BBDC: Before Bottom Dead Center. Measured in degrees. BILLETS: The blank shafts that the camshafts are made from. BTDC: Before Top Dead Center. Measured in degrees. CAM FOLLOWER / TAPPET: Usually a flat faced or roller companion to the camshaft that transfers the action of the camshaft to the rest of the valve train by sliding or rolling on the cam lobe. CAM LIFT: This is the maximum distance that the cam pushes the follower when the valve is open. This is different from valve lift. See Gross Valve Lift. CAM LOBE: The parts of the camshaft that create the valve movement. CAM MASTER: Design of the cam transferred to a template or master. The master is then installed in the cam grinding machine to generate the shape of the lobes of the production cam.
    [Show full text]