A piping system for an open loop surface water heat pump system is shown in Figure $1.$ The

system description can be divided into four sections:

The water is drawn from the lake and travels through $80$ m of piping en route to the

pump suction. The screened inlet and elbow have a total $K$ value of $4$ and are at a

depth $z_{\text{i}\text{n}\text{t}\text{e}\text{r}}$

The pump is placed in a dry sump a distance of $z_{\text{s}\text{u}\text{r}\text{n}\text{a}\text{n}}$ below the free surface of the

water.

The water leaving the pump is carried through $20$ m of piping with two elbows

$(K=0\mathrm{.}45$ for each elbow$)$ to a plate frame heat exchanger, which has a design head loss

of $60$ feet at $790$ GPM flow.

The water leaving the plate frame heat exchanger travels through $50$ m of pipe, two

elbows, and a diffuser. The elbows and the diffuser in this section have a total $K$

value of $10.$

The atmospheric pressure is $101$ kPa $.$ The piping is $6^{\text{'}\text{'}}$ SDR$-11$ HDPE pipe. The distances are

as follows:

$z_{\text{s}\text{t}\text{a}\text{i}\text{n}}=6m$

Figure I Open loop surface water heat pump system

A Word template for your solution has been uploaded. Please submit these pages, filled in$.$ Use

Excel$/$VBA or EES and water properties that are computed for the specified temperature.

HW A$5$ Solution template

At winter operating conditions with a water temperature of $4C,$ find the flow

rate, assuming there is adequate $NPS{H}_A.$ Plot the pump curve and system curve.

Fill in the following intermediate values and answer:

At winter operating conditions with the flow rate determined in part $1,$ find the

$NPS{H}_A$ at the pump inlet. Fill in the following intermediate and final values.

MAL $35240154$

Find the $NPS{H}_R($ f $)$ for the pump at the operating condition determined in Part $1.$

Can the pump be expected to operate at this condition?