工程流体力学章节测试课后答案2024春

第八章测试

1.A 2-in. diameter shaft is supported by two sleeves, each of length = 2 in. The internal diameter of the sleeves is 2.1 in. The radial space between the shaft and the sleeves is filled with an oil of viscosity = 8 × 10-3 lb-s/ft2. If the shaft is rotated at a speed of 600 rpm, the viscous torque (ft-lb) on the shaft is most nearly （ ）。
A:0.15 B:6.40 C:3.20 D:0.64
答案:A
2.The force amplification can be realized by increasing the acting area. True or False? （ ）
A:错 B:对 3.The pressure amplification can be realized by increasing the acting area.  （ ）
A:对 B:错 4.How to reduce hydraulic shock? （ ）。
A:Increase the diameter of the pipeline B:shorten the length of the pipeline as far as possible C:Extend the time of valve closing D:Limit pipeline flow rate