Manufacturer's performance data for a water pump operating at 1725 rpm and room temperature (Example 14–11)* V, cm/s Н, ст Npump 100 180 32 200 185 54 300 175 70 400 170 79 500 150 81 600 95 66 700 54 38
After graduation, you work for a pump manufacturing company. One of your company’s best-selling products is a water pump, which we shall call pump A. Its impeller diameter is DA = 6.0 cm, and its performance data when operating at n. A = 1725 rpm (?A = 180.6 rad/s) are shown in Table.The marketing research department is recommending that the company design a new product, namely, a larger pump (which we shall call pump B) that will be used to pump liquid refrigerant R-134a at room temperature. The pump is to be designed such that its best efficiency point occurs as close as possible to a volume flow rate of V. B = 2400 cm3 /s and at a net head of HB = 450 cm (of R-134a). The chief engineer (your boss) tells you to perform some preliminary analyses using pump scaling laws to determine if a geometrically scaled-up pump could be designed and built to meet the given requirements. (a) Plot the performance curves of pump A in both dimensional and dimensionless form, and identify the best efficiency point. (b) Calculate the required pump diameter DB, rotational speed n.B, and brake horsepower bhpB for the new product.
Trending now
This is a popular solution!
Step by step
Solved in 2 steps with 1 images
