A cooling load with a specified enthalpy difference
A fictional air-handling exercise supplies dry-air mass flow of two kilograms per second. Air entering a cooling process has an enthalpy of sixty kilojoules per kilogram of dry air, and leaving air has forty kilojoules per kilogram of dry air. The stated values already include the relevant sensible and latent contributions under the exercise model. A proposed answer uses the dry-bulb temperature change alone, although no heat-capacity value or temperature data has been supplied. The design team must identify the correct energy boundary and distinguish cooling duty from electrical input. The exercise does not provide a coil selection, outdoor-air requirement, condensate arrangement, refrigerant instruction or current regional ventilation standard.
1. Calculate the modeled cooling duty.
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Cooling duty is dry-air mass flow times the enthalpy decrease:2*(60-40)=40kJ/s=40kW. The enthalpy difference already represents the stated total process effect; adding an invented separate latent load would double count.
2. Can the electrical input be inferred?
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No. Electrical input requires the specified equipment and system efficiency or COP with a compatible boundary, including relevant auxiliaries. A40kWthermal duty is not automatically40kWof electrical power.