Using isothermal jet theory, estimate the length of an ethane–air diffusion fl ame for an initial velocity of 5 cm / s. The velocity profi le issuing from the 10-mm-diameter port is uniform. Both the air and ethane are at 300 K and 1 atm. The viscosity of ethane is approximately 9.5 · 10−6 N-s / m2. Compare your estimate using an average viscosity, ( μair + μethane ) / 2, with the predicted value from Roper’s experimental correlations.

Afull journal bearing has a journal diameter of 27 mm, with a unilateral tolerance of -0.028 mm. the bushing bore has a diameter of 27.028 mm and a unilateral tolerance of 0.04 mm. the l/d ratio is 0.5. the load is 1.3 kn and the journal runs at 1200 rev/min. if the average viscosity is 50 mpa-s, find the minimum film thickness, the power loss, and the side flow for the minimum clearance assembly.

The higher the astm grain-size number, the coarser the grain is. a)-true b)-false

Ajournal bearing has a journal diameter of 3.250 in with a unilateral tolerance of 20.003 in. the bushing bore has a diameter of 3.256 in and a unilateral tolerance of 0.004 in. the bushing is 2.8 in long and supports a 700-lbf load. the journal speed is 900 rev/min. find the minimum oil film thickness and the maximum film pressure for both sae 20 and sae 20w-30 lubricants, for the tightest assembly if the operating film temperature is 160°f. a computer code is appropriate for solving this problem.