Page 57 - Automotive Engineering

CH AP TER 2 .1 Measurement of torque, power, speed and fuel consumption

Number of cylinders N cyl Transverse critical frequency N t cycles/min
Mean turning moment M mean Nm Dynamic torsional stiffness
Indicated mean effective pressure p i bar of coupling C c Nm/rad
Cylinder bore B mm Damping energy ratio j
Stroke S mm Modulus of elasticity
Component of tangential effort T m Nm of shaft material E Pa
Amplitude of vibratory torque T v Nm Modulus of rigidity of shaft material G Pa
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Engine speed corresponding to n c N c rev/min (for steel, E ¼ 200 10 Pa,
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Maximum shear stress in shaft s N/m 2 G ¼ 80 10 Pa)
Whirling speed of shaft N w rev/min

References

1. Den Hartog, J.P. (1956) Mechanical 4. Neale, M.J., Needham, P. and Horrell, R. 7. Young, W.C. (1989) Roark’s Formulas
Vibrations, McGraw-Hill, Maidenhead, (1998) Couplings and Shaft Alignment, for Stress and Strain, McGraw-Hill,
UK. Mechanical Engineering Publications, New York.
2. Ker Wilson, W. (1963) Practical Solution London. 8. BS 6613 Methods for Specifying
to Torsional Vibration Problems (5 vols), 5. Rulebook, Chapter 8. Shaft vibration and Characteristics of Resilient Shaft
Chapman and Hall, London. alignment, Lloyd’s Register of Shipping, Couplings.
3. Ker Wilson, W. (1959) Vibration London. 9. BS 5265 Parts 2 and 3 Mechanical
Engineering, Griffin, London. 6. Pilkey, W.D. (1997) Peterson’s Stress Balancing of Rotating Bodies.
Concentration Factors, Wiley, New York.

reading
reading
Further reading
Further
Further
BS 4675 Parts 1 and 2 Mechanical BS 6716 Guide to Properties and Types of Nestorides, E.J. (1958) A Handbook of
Vibration in Rotating Machinery. Rubber. Torsional Vibration, Cambridge
BS 6861 Part 1 Method for Determination of University Press, Cambridge.
Permissible Residual Unbalance.

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