Measuring Engine Performance ME 115 Laboratory Spring 2008.

Slides:



Advertisements
Similar presentations
Engine Parameters.
Advertisements

Thermodynamics AP Physics Chapter 15.
Chapter 3 Engine Operation
Engine Geometry BC L TC l VC s a q B
Engine Terminology Engine Measurement Lesson 8 March 2008.
Lab T1: Compression Ignition (Diesel) Engine Lab Instructor: M
STUDENT NAME: (1) Patel Vidhi A.
THERMAL ENGINEERING (ME 2301 )
Conceptual & Thermodynamic Description of Expansion in I.C. Engine P M V Subbarao Professor Mechanical Engineering Department The Actual & Useful Extent.
Department of Mechanical Engineering ME 322 – Mechanical Engineering Thermodynamics Lecture 28 Internal Combustion Engine Models The Otto Cycle The Diesel.
Effect of Piston Dwell on Engine Performance P M V Subbarao Professor Mechanical Engineering Department Sufficiency of time to Execute a Process…..
Internal Combustion Engine Theory
GAS POWER CYCLES Chapter 9. Introduction Two important areas of application for thermodynamics are power generation and refrigeration. Two important areas.
Department of Mechanical Engineering ME 322 – Mechanical Engineering Thermodynamics Lecture 25 Comparison to Carnot’s Heat Engine Effects of Boiling and.
Lesson 3: Reciprocating Engine Theory Of Operation
I.C. ENGINES Practical No: 5 (22 Apr, 2014). Indicated Power P i Date Definition of P i Is the actual power developed by the engine Burning of fuel (
Diesel Engine Classification
Pre-test Study Guide Thermodynamics Laws Q=m C ∆T Q = m L P V = n R T ∆U = Q – W Effic. = T h -T c /T c Other Laws W = F * d P = W / t P = F / A Vocabulary.
© Goodheart-Willcox Co., Inc. Permission granted to reproduce for educational use only Publisher The Goodheart-Willcox Co., Inc. Tinley Park, Illinois.
Internal Combustion Engines. Ideal Diesel Cycle Ideal Diesel Cycle.
Experiment #4 IC Engine.
Internal Combustion Engine Testing
I.C. ENGINES LECTURE NO: 13 (28 Apr 2014).
Internal Combustion Engine (ICE) Performance ME 252 Thermal Fluid Systems G. Kallio.
Thermo & Stat Mech - Spring 2006 Class 5 1 Thermodynamics and Statistical Mechanics Heat Engines and Refrigerators.
Thermodynamic Analysis of Internal Combustion Engines P M V SUBBARAO Professor Mechanical Engineering Department IIT Delhi Work on A Blue Print Before.
Subject: thermal efficiency, mechanical efficiency, volumetric efficiency Student: 1391/12/5.
MEL713 – DESIGN OF I.C. ENGINES: COMPONENTS & SUB-SYSTEMS P M V Subbarao Professor Mechanical Engineering Department Laboratory & Design Practicals …..
Engine Size and Measurements
Thermodynamic Cycles Air-standard analysis is a simplification of the real cycle that includes the following assumptions: 1) Working fluid consists of.
Work Distribution Analysis of I.C. Engine Cycles P M V Subbarao Professor Mechanical Engineering Department Find true Scope for Development….
8 CHAPTER Gas Power Cycles.
Measuring Engine Performance
Strategies for Complete Expansion in I.C. Engine P M V Subbarao Professor Mechanical Engineering Department Achieve Maximum Work Output….
Thermodynamics AP Physics Chapter 15. Thermodynamics 13.3 Zeroth Law of Thermodynamics.
Gas Power Cycles Thermodynamics Professor Lee Carkner Lecture 17.
ENGINE DESIGN AND OPERATION. ENGINE CLASSIFICATIONS n VALVE ARRANGEMENT n CAMSHAFT LOCATION n IGNITION TYPE n CYLINDER ARRANGEMENT n NUMBER OF CYLINDERS.
Chapter 9 Gas Power Cycles Study Guide in PowerPoint to accompany Thermodynamics: An Engineering Approach, 8th edition by Yunus A. Çengel and Michael.
APPLIED THERMODYNAMIC INTERNAL COMBUSTION ENGINES
AR Thermodynamics I Fall 2004 Course # 59:009 Chapter 9, Section 2 Professor Ratner.
INTERNAL COMBUSTION ENGINES. EXTERNAL VS INTERNAL  external- combustion engine  typically steamed powered  heated water would produce steam to increase.
2 nd Law of Thermodynamics Heat Engines. 2 nd Law Heat flows naturally from high temperature to low temperature, never in reverse.
Chapter 20 Lecture 35: Entropy and the Second Law of Thermodynamics HW13 (problems):19.3, 19.10, 19.44, 19.75, 20.5, 20.18, 20.28,
Unit 61: Engineering Thermodynamics Lesson 12: Combustion Engines.
Basic Mechanical Engineering, First Edition by Dr Pravin Kumar Copyright © 2013 Dorling Kindersley (India) Pvt. Ltd. Chapter 6 Internal Combustion Engines.
Engine Technology Gasoline Engine Work moving of an object against an opposing force by a push, pull or lift measured in terms of distance and force, or.
Engines—examples and efficiency
PROJECT TITLE AND TEAM MEMBERS
Gas Power Cycles.
Engine Parameters.
OPERATING PRINCIPLES OF PISTON ENGINES
Unit 61: Engineering Thermodynamics
Strategies for Complete Expansion in I.C. Engine
Timing and Interference
The IC Engine: Why… By: Matthew King.
Mechanical Losses in An Engine
Combustion and Power Generation Engineering Thermodynamics ( )
Engineering Thermodynamics ME-103
SI Engine Cycle Actual Cycle Intake Stroke Compression Power Exhaust
THE OTTO CYCLE (engine)
Thermo-Economic Analysis of Otto Cycle
Measuring Engine Performance
The Otto Cycle By: Vijai Sookrah
Ch. 10 Heat Transfer in Engines
Energy Conversion Engines take heat energy and convert it into mechanical energy. Motors take electrical energy and convert it into mechanical energy.
Thermodynamic Analysis of Internal Combustion Engines
Engines—examples and efficiency
Engine Parameters.
Engines—examples and efficiency
Chapter 5: The Second Law of Thermodynamics
Presentation transcript:

Measuring Engine Performance ME 115 Laboratory Spring 2008

Otto Cycle Review Cengel & Boles, Thermodynamics: An Engineering Approach, 2006.

Common terms used to compare engine performance Brake power (bp): net power output of an IC engine Torque: A force acting through a radius RPM: engine speed, in rotations per minute Specific fuel consumption (sfc): rate of fuel consumption per unit of brake power

Mean Effective Pressure MEP: a fictitious pressure that, if acted on the piston during the entire power stroke, would produce the same amount of net work as that produced during the actual cycle (Cengel & Boles, 2006) If the MEP goes up, the cylinder volume can go down and still achieve the same power output

Mean Effective Pressure, cont. Indicated MEP (imep): uses the total power output minus the power needed for the intake and exhaust stokes (indicated power) Brake MEP (bmep): the power used to overcome friction in the cylinder is also subtracted; this term is used more often than the imep

Brake Thermal Efficiency Brake thermal efficiency: brake power/rate of heat output for complete combustion Brake thermal efficiency=indicated thermal efficiency* mechanical efficiency Mechanical efficiency: related to the amount of power used to overcome friction

Carnot Efficiency To see how well our engine is doing, we can compare our brake thermal efficiency to the Carnot efficiency Remember that the Carnot efficiency is the best we can do!   =1-(T low /T high ), where T’s are in absolute scale  We could estimate T high as our exhaust temperature  T low is our ambient temperature

Engine Irreversibilities Heat transfer from the cylinder wall during compression: will this irreversibility be larger for slow or fast engine speeds? Pressure losses across the valves: will this irreversibility be larger for slow or fast engine speeds? Frictional work due to sliding ring seals and other rotating components: will this irreversibility be larger for slow or fast engine speeds?

Energy Efficiency Variation with Engine Speed Decher, 1994, Energy Conversion: Systems, Flow Physics and Engineering.