Missing Assumption/Information? (HVAC/R)

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The discussion revolves around a refrigeration plant rated at 1,200,000 Btu/hr, seeking to determine the maximum allowable wet-bulb temperature for water flow rates of 240 or 320 gpm. The poster expresses difficulty in starting the problem due to a lack of state information for the air, making it challenging to proceed without making numerous assumptions. They recognize that the problem involves cooling with dehumidification, indicating a need for a constant wet-bulb temperature throughout the process. The poster is unsure how to utilize the total heat rating to find the sensible heat ratio (SHR) without assuming complete heat transfer from the water to the air. They seek guidance on valid assumptions to help initiate a solution.
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Homework Statement



A refrigeration plant is rated at 1,200,000 Btu/hr with a cooling range of 10°F and a cold water temperature of 80°F. What is the maximum wet-bulb temperature allowable for 240 or 320 gpm?

Homework Equations





The Attempt at a Solution



I am not really sure where to even start this problem. I've poured over this problem multiple times for the last couple weeks but I can't seem to figure out what to do here. I've done the basic steady state mass flow balances on the air and water flows but without any state information given for the air I'm not sure how to get to an answer without making quite a few assumptions.

Things I do realize:

1) It asks for a maximum allowable wet bulb temperature which means that it must be a constant through out the process. This also indicates that the process must be cooling with humidification or heating with dehumidification. Therefore the process must be cooling with dehumidification (evaporative cooling??).

That's really about it. If I try to use the total heat rating to find SHR, that would rely on me assuming all of the inlet water gets transferred to the air (which is insane at those flow rates). Can anyone help me even get started here? I can't think of a valid assumption that could help me solve.

Thanks ahead of time for anyone's help.
 
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