4. A typical diesel main journal bearing has the following characteristics: R=0.045m, L = 0.04m, c...

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4. A typical diesel main journal bearing has the following characteristics: R=0.045m, L = 0.04m, c = 0.000045m, &=0.7, U = 12.7m/s (2700rpm). The oil used is SAE30 and the working temperature is 82C. (use the charts bellow) Find load carried, flow required to prevent starvation, and the friction coefficient. Hint: Use the equations from the journal bearings lecture to find the unknowns. Total load carried c 12:2 | 16(1-82)* 71/2 4 E - Friction coefficient = F/W 8Rc Flow The flow (per unit length) in a journal bearing is obviously in circumferential direction and is given by: (1-823/2 * 1 (0.62 . (0.62+12 9x= -h dp Uh 12 dx + 2 avoid starvation of lubricant Q=U,Les KINEMATIC VISCOSITIES Grade Systems SAYBOLT VISCOSITIES eSt 40C c5t 100C ISO SAE SAE AGMA ENGINE OIL GEAR OIL SUS SUS 210F 100F 800- -200 4000 680 600- -3000 500- 140 400- 350 -125 320 300 250- 20 -100 220 90 90 200 16- 100 8888885 150- 150 70 85W 100 10- 80- 20 50- 102500 2000 1000 1500 1200 F1000 800 600 500 400 300 250 200 45 150 10W GB 20 SW 15- 15 10- 10 100 88 23 4. A typical diesel main journal bearing has the following characteristics: R=0.045m, L = 0.04m, c = 0.000045m, &=0.7, U = 12.7m/s (2700rpm). The oil used is SAE30 and the working temperature is 82C. (use the charts bellow) Find load carried, flow required to prevent starvation, and the friction coefficient. Hint: Use the equations from the journal bearings lecture to find the unknowns. Total load carried c 12:2 | 16(1-82)* 71/2 4 E - Friction coefficient = F/W 8Rc Flow The flow (per unit length) in a journal bearing is obviously in circumferential direction and is given by: (1-823/2 * 1 (0.62 . (0.62+12 9x= -h dp Uh 12 dx + 2 avoid starvation of lubricant Q=U,Les KINEMATIC VISCOSITIES Grade Systems SAYBOLT VISCOSITIES eSt 40C c5t 100C ISO SAE SAE AGMA ENGINE OIL GEAR OIL SUS SUS 210F 100F 800- -200 4000 680 600- -3000 500- 140 400- 350 -125 320 300 250- 20 -100 220 90 90 200 16- 100 8888885 150- 150 70 85W 100 10- 80- 20 50- 102500 2000 1000 1500 1200 F1000 800 600 500 400 300 250 200 45 150 10W GB 20 SW 15- 15 10- 10 100 88 23