ROSE-HULMAN Institute of Technology

Problem 1

A piping system made of 25 m of 4-nominal schedule 40 galvanized steel pipe conveys water from a pressurized tank maintained at p₁. The fittings are all regular and welded and the check valve is a swing type. The entrance to the piping system is equipped with a basket strainer. Find the system curve for the piping system. That is, find the required pressure p₁ expressed in head (p₁/ρg) as a function of the volumetric flow rate through the system. Let the volumetric flow rate vary from 0.015-0.040 m³/s.

Problem 2

Liquid ammonia at 10°C is to be transferred from one large container to another large container. As indicated by the figure, a single pump is to be used in a parallel piping system. For the following three options, find the power required to pump 85 liters/s of the liquid ammonia. The single line containing the pump is very short.

1. Pipe 1 only
2. Pipe 1 and 2 in parallel
3. Pipe 1, 2 and 3 in parallel

Pipe D (mm) L (m) ε (mm) 1 150 300 0.3 2 125 330 0.15 3 100 360 1.5

Problem 3

Water enters a counterflow, double-pipe heat exchanger at a rate of 70 kg/min and is heated from 15°C to 60°C by an oil with a specific heat of 1.9 kJ/kg-K. The oil enters at 116°C and leaves at 27°C. The overall heat transfer coefficient is 300 W/m²-K. What heat transfer area is required?