Help in trying to set up an equation

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In summary, the question at hand is which of the two options, an aluminum intercooler cooled by ambient air or injecting a 50/50 mixture of liquid methanol/water, will provide better cooling for a turbocharged engine. To accurately calculate this, you will need specific data on the specific heat capacities, flow rates, and densities of the air and methanol/water mixture. By comparing the amount of heat energy transferred from the charge air temperature to each cooling method, you can determine which one is more effective.
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Joe_K
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Here is what I am trying to do. I want to tell which of the following two options will give me a cooler charge air temperature into my car's engine.

The turbocharger on the engine is pushing 42 lb/min of airflow into the engine, which first goes through an intercooler in order to cool the charge air temperature, which ENTERS the intercooler at a high temperature ((Ti) approx. 350 degrees F., but this is a rough estimate).

The intercooler is made of aluminum, and is cooled by ambient air, which dissipates heat via fins on the intercooler. The total internal volume of the intercooler is 318.5 in^3.

The outlet temperature (Tf) is 130 degrees F.

Now, what I am trying to figure out is if injecting a 50/50 mixture of liquid methanol/water would decrease the final temperature (Tf) more than the intercooler would. Basically, which provides better cooling?

The injection rate of the methanol/water mixture would be 175 mL/min.

The help I need involves setting up the problem. Are there any data that I am missing that will be required in order to accurately calculate which will cool the air better? Any help in setting up the problem would be appreciated, thanks.
 
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In order to accurately calculate which will cool the air better, you will need to determine the specific heat capacity of the methanol/water mixture and the specific heat capacity of the air. You will also need to determine the specific heat capacity of the aluminum intercooler. Additionally, you will need to know the flow rate of the air through the intercooler and the flow rate of the methanol/water mixture that is being injected. Finally, you will need to know the density of both the air and the methanol/water mixture. With this information, you can then calculate the amount of heat energy (in BTUs) that is transferred from the charge air temperature to the ambient air and the amount of heat energy (in BTUs) that is transferred from the charge air temperature to the methanol/water mixture. By comparing these two values, you can determine which cooling method will be more effective.
 

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