【Daily Question: Pump Equipment】Multiple-choice Question 2018.12.10

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This post was last edited by 3983596_FPPZ on 2018-12-10 at 14:26. For bk03.jpg: Rules for multiple-choice questions: 1. If the answer to each question is incorrect, participants will still receive a reward; 2. Wealth； 2. A correct answer rewards 6 wealth points ； 3. Rewards for answers are available once per person only ； 4. Each reply allows for only one management rating ； 5. The answer and its explanation will be visible after responding ； 6. The reward is valid for 48 hours. Studying* and winning awards again; come by here every day. It is known that a centrifugal pump is used to transport high-concentration methanol solution at room temperature. The specific gravity of methanol is 0.8, the pump’s flow rate is 50 m3/h, the head is 80 m, the inlet pressure is 2 kgf/cm2, the rotation speed is 2900 r/min, and the motor power is 22 KW. Which of the following outlet pressures is closest to the actual value? (Single choice) A 1.0 MPa B 0.84 MPa C 0.64 MPa D 2.64 MPa E 10 kgf/cm2 F 1.2 MPa. Answer: B. The outlet pressure = inlet pressure + head * specific gravity. Converting the inlet pressure: 2 kgf/cm2 = 2 * 9.81/100 = 0.196 MPa. The pressure difference generated by the head: 0.8 * 80 * 9.81/1000 = 0.628 MPa. Adding these two values together gives an outlet pressure of 0.196 + 0.628 = 0.824 MPa. Therefore, option B is the closest answer. Be sure to pay attention to unit conversions: D