Dynamic Behavior of Three-wheeled Vehicle Under Random Road Characteristics Using FEM
In general three wheelers are one of the most popular city transport vehicles in the world and particularly in developing countries especially for short hauls. In the present work finite element model of three wheeled motor vehicle chassis has been developed using ANSYS software by taking into account the chassis longitudinal/cross members, the suspensions, the axles and the tires. Modal analysis is carried on the three wheeled motor vehicle chassis using Block Lanczo's technique to obtain the natural frequencies and mode shapes. Vertical dynamic response of the three wheeled motor vehicle chassis has been carried in the frequency domain by performing the spectrum analysis using ANSYS software. When the vehicle moving at 45 kmph on different Indian and International roads, and the response is obtained at four significant points i.e. at node 2 (rear part of the chassis sprung mass), at node 8 (passenger seat position), at node 657 (rear axle) and at node 34 (steering position). The response i.e. power spectral density of acceleration is compared between the Indian and International roads and different modes which affect the passenger comfort are also discussed using spectrum analysis. Parametric study has also been carried out using the finite element model to study the effect of various parameters and to find the optimum values both quantitatively and qualitatively, in the ride response of the vehicle. Finally based on the above analysis certain recommendations are made about manufacturer point of view.
Ride Analysis of Three Wheeled Vehicle Using MATLAB/Simulink
A spatial six degree freedom mathematical model of a three wheeled vehicle (TWV) used in Asian countries has been developed using multi body system approach. The model includes suspension and tyre compliance. The model consists of a single sprung mass (vehicle body) connected to three unsprung masses (three wheels) at each corner. The suspensions and tires are modeled as springs and linear damper elements. The model consists of six degrees of freedom because the body has three degrees freedom for bounce, pitch and roll motions and each unsprung mass have bounce motion. Vertical dynamic response of the TWV has been found when the vehicle is moving at 45 kmph on random road surface. Damping ratios and natural frequencies are obtained using Eigen value analysis. Ride analysis has been carried out in the frequency domain by performing the spectrum analysis using MATLAB/Simulink.
Tractors and Their Power Units
1 Development of the Tractor.- Tractor Types.- Some World Variations in Tractors.- Functions of a Farm Tractor.- Sources of Energy.- Energy Conversion Devices.- The Future Engine.- Trends in Tractor Design.- 2 Thermodynamic Principles of Internal-Combustion Engines.- Specific Heat.- Entropy.- Energy Changes.- Constant-Volume Changes.- Constant-Pressure Changes.- Isothermal Changes.- Adiabatic or Constant-Entropy Changes.- General or Polytropic Changes.- Changes in an Adiabatic Expansion of a Perfect Gas.- Determination of the Value of n from an Actual Compression Line.- Equations for Nonflow Processes.- 3 Internal-Combustion Engine Cycles.- Simplifying Assumptions.- The Ideal Air-Standard Otto Cycle.- The Ideal Air-Standard Diesel Cycle.- Actual Cycles and Causes for Deviation from the Ideal.- 4 Fuels and Combustion.- Sources of Fuels.- Chemical Composition of Petroleum.- Petroleum Refining.- Combustion.- Gasoline Tests and Their Significance.- Antiknock Quality.- Factors Affecting the Octane Number Requirement.- Volatility.- Distillation.- Reid Vapor Pressure Test.- Sulfur Content.- Corrosion Test.- Gum Content.- Gravity.- Heating Values.- Gasoline Additives.- Diesel Fuel Tests and Their Significance.- Cetane Number.- Heating Value of Diesel Fuel.- Viscosity.- Carbon Residue.- Flash Point.- Pour Point and Cloud Point.- Ash Content.- Diesel Fuel Additives.- Alternate Fuels.- 5 Engine Design.- Engine Design-General.- Stroke-to-Bore Ratio.- Crankshafts and Firing Orders.- Tractor Engine.- Valve Design.- Valve Materials, Design, and Application.- Valve Timing.- Valve Clearance Adjustment.- Valve Seats.- Valve-Opening Area.- Cams.- Combustion Chamber Design.- Effect of Compression Ratio.- Piston Crank Kinematics.- Inertia Force of Connecting Rod.- Inertia Force of Single-Cylinder Engines.- Crank Effort.- Flywheels.- Balance of Single-Cylinder Engines.- Balance of Multicylinder Engines.- Principles of CI Engine Operation.- Construction of Diesel Engines.- Combustion Chamber Design.- Fuel-Injection Systems.- Fuel Injectors.- Turbochargers.- Matching of Turbocharger to Engine.- Aftercooling.- Engine Noise.- 6 Electrical Systems.- Battery.- Starting Motor.- Electrical Charging.- Battery Ignition System with Breaker Points.- Magneto Ignition System.- Ignition Timing.- Spark Plugs.- Sensors.- Environmental Problems.- 7 Engine Accessories.- Speed Control.- Principles of Centrifugal Governor Action.- Spark Arresters.- Mufflers.- Air Cleaners.- Air Inlet Location.- Precleaners.- Dry-Type Air Cleaner.- Dust Composition.- Air Cleaner Tests.- Engine Cooling Systems.- Cooling Load.- Heat Transfer.- Air Cooling.- Radiator Design.- Radiator Construction.- Temperature Control.- Antifreeze Materials and Coolants.- Corrosion and Radiator Deposits.- Pressure Cooling.- Quantity of Air.- Fans.- Engine Cooling Summary.- 8 Lubrication.- Types of Lubricants.- Properties of Lubricants.- Viscosity.- Classification of Oil by Viscosity.- Classification by Service.- Universal Tractor Oils.- Oil Additives.- Journal Bearing Design.- Oil Contamination.- Oil Filters.- Lubricating Oil Systems.- 9 Human Factors in Tractor Design.- Operator Exposure to Environmental Factors.- Operator Exposure to Noise.- Operator Exposure to Vibration.- The Operator-Machine Interface.- Noise and Vibration Control.- Operator Seating.- Sound Control in Operator Enclosures.- Spatial, Visual, and Control Requirements of the Operator.- Rollover Protection for Wheeled Agricultural Tractors.- Thermal Comfort in Operator Enclosures.- Safety.- 10 Traction.- Traction Mechanics.- Mohr-Coulomb Failure Criteria.- Traction Performance Equations.- Traction Prediction from Dimensional Analysis.- Performance of Four-Wheel, Tandem, and Dual Tires.- Tire Size, Load, and Air Pressure Relationship.- Radial-Ply Construction.- Tread Design.- Effect of Lug Spacing.- Traction Improvement.- Tracks.- Tire Testing.- Traction Devices for Paddy Fields.- 11 Mechanics of the Tractor Chassis.- Simplifying Assumptions.- Equations of Motion.- Static Equilibrium Analysis-Force Analysis.- Static Equilibrium Analysis-Maximum Achievable Drawbar Pull.- Static Equilibrium Analysis-Four-Wheel-Drive.- Longitudinal Stability.- The Tractor as a 2-Degree-of-Freedom Vibratory System.- Transient and Steady-State Handling.- Lateral Stability in a Steady-State Turn.- Three-Dimensional Static Analysis.- Center of Gravity Determination.- Moment of Inertia Determination.- 12 Hydraulic Systems and Controls.- Hydraulic Component Symbols.- Hydraulic Components.- Motor Performance.- Accumulators.- Valves.- Hydraulic Fluids.- Classification of Hydraulic Controls.- Draft Sensing.- Automatic Control.- Complete Hydraulic System.- Power Steering.- Noise in Hydraulic Systems.- Hitches.- Tractor Kinetic Energy.- Integral Hitch Systems.- Three-Point Hitches.- Quick-Attaching Coupler for Three-Point Hitches.- 13 Transmissions and Drive Trains.- Complete Drive Train.- Transmission Types.- Friction Brakes and Clutches.- Spur and Helical Gears.- Bevel Gears.- Gear Design.- Planetary Gear Systems.- Differentials.- Transmission Drive Shafts.- Antifriction Bearings.- Drive Train Speeds and Loads.- Electronic Transmission Controls.- Torsional Vibration.- Computer Simulation.- 14 Tractor Tests and Performance.- Tractor Performance Criteria.- Power Measurement Methods.- Absorption Dynamometers.- Electric Direct Current Dynamometers.- Shop-Type Dynamometers.- Drawbar Dynamometers.- Torsion Dynamometers.- Chassis Dynamometer.- Power Estimating-Field Method.- Air-Supply Measurement.- Engine Pressure Indicators.- Fuel Flow Meter.- The Nebraska Tractor Tests.- Globalization of the Tractor Industry.- Correction for Atmospheric Conditions.- Torque Curves.- Engine Performance.- Efficiency of Tractor Engines.- Actual Power Output and Fuel Consumption.- Tractor Reliability.- Appendixes.- A Standards for Agricultural Tractors.- B Standard Graphical Symbols.- C Agricultural Tractor Tire Loadings, Torque Factors, and Inflation Pressures-SAE J709d.- D Conversion Factors.