6. The turning moment diagram for a four stroke gas engine may be assumed for simplicity to be repre- sented by four triangles, the areas of which from the line of zero pressure are as follows: Expansion stroke = 3550 mm²; exhaust stroke = 500 mm²; suction stroke = 350 mm²; and compres- sion stroke 1400 mm². Each mm² represents 3 N-m. Assuming the resisting moment to be uniform, find the mass of the rim of a flywheel required to keep the mean speed 200 r.p.m. within ± 2%. The mean radius of the rim may be taken as 0.75 m. Also determine the crank positions for the maximum and minimum speeds. [Ans. 983 kg; 4° and 176° from I. D. C]

6. The turning moment diagram for a four stroke gas engine may be assumed for simplicity to be repre- sented by four triangles, the areas of which from the line of zero pressure are as follows: Expansion stroke = 3550 mm²; exhaust stroke = 500 mm²; suction stroke = 350 mm²; and compres- sion stroke 1400 mm². Each mm² represents 3 N-m. Assuming the resisting moment to be uniform, find the mass of the rim of a flywheel required to keep the mean speed 200 r.p.m. within ± 2%. The mean radius of the rim may be taken as 0.75 m. Also determine the crank positions for the maximum and minimum speeds. [Ans. 983 kg; 4° and 176° from I. D. C]

International Edition---engineering Mechanics: Statics, 4th Edition

4th Edition

ISBN:9781305501607

Author:Andrew Pytel And Jaan Kiusalaas

Publisher:Andrew Pytel And Jaan Kiusalaas

Chapter7: Dry Friction

Section: Chapter Questions

Problem 7.70P: Solve Sample Problem 7.16 if the contact pressure under the polisher varies parabolically from p0 at...

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