Estimating Energy Needed for Cooling Tunnel with 177.21kg/s Water Flow

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To estimate the energy needed for a cooling system with a water flow of 177.21 kg/s and a thermal output of 37,125 megawatts from trains, the relevant formula for thermal power is p=(m*c*dT)/t. The discussion highlights the need to determine the temperature difference (dT) to apply this formula effectively. Additionally, there is confusion regarding the term "energy necessary to run the system," which may require further information related to fluid mechanics. The participants suggest that understanding the Carnot heat engine principles might be relevant, but the focus remains on calculating the necessary power for the cooling system. Clarification on mass M and the specific conditions of the cooling process is also sought.
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A cooling system that pumps 177,21 kg/s of water in a tunnel warmed by trains with an average thermal output of 37,125 mega watts. I have to estimate the energy which is necessary to run the system in order to cool down water with the mass M. Both in the general case and on the assumption that the new water temperature is nearly the same.

I have never made an estimation in physics before. Do I have to calculate? Is there a difference between both cases?

Normally the formula for thermal power is p=(m*c*dT)/t. Can I apply it?

Thank you for your support.
 
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You have a mass flow rate \dot{m}=177,21 kg/s multiplied by the specific heat and temperature difference should equal the power. But what it the temperature difference.

Also, one is asking for the "energy which is necessary to run the system", which sounds like a fluid mechanics or hydraulics problem, and one would need more information.

What is mass M?
 
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