(b) A commercial building is planning a groundwater heat pump system similar to the arrangement shown in Figure Q3. The
Posted: Mon May 09, 2022 9:28 am
(b) A commercial building is planning a groundwater heat pump system similar to the arrangement shown in Figure Q3. The peak cooling load for the building is 100 kW. The groundwater temperature is 15°C, and the HVAC engineer has designed the heat pump loop to float up to 30°C (heat pump inlet) before energizing the well pump. The building loop fluid is pure water, and the peak design flow requirement for the heat pump is 300L/min (5.0 kg/s). From the heat pump manufacturer's catalogue data, the COP of the heat pump at 30°C is 4.0. (1) Calculate the load on the heat exchanger. (20%) (i) Calculate the fluid temperature exiting the heat pump on building side. (20%) (iii) Calculate the required groundwater flow rate. (40%) Assumptions: The heat exchanger effectiveness ε = 0.80. The specific heat of groundwater is 4.2 kJ/kg-K Minimum capacity rate (Cmin) is on the groundwater side. Heat Pump Circulation Pump Heat Exchanger Well water Pump Injection Supply well well Figure Q3. Schematic of a commercial/institutional ground heat pump system.