Process water with a specific heat capacity of 4.182 KJ Kg-1 K -1 flows at a rate of 0.050 Kg s-1 through a heat exchanger where its temperature is increased from 16C to 85C. Heat is supplied by exhaust gases (mean specific heat capacity of 1.075 KJ Kg-1 K-1) which enter the heat exchanger at a temperature of 420C. If the mass flowrate of the exhaust gases is 0.044 kg s-1, determine their outlet temperature.
Energy flow = (specific heat) X (mass flow rate) X (delta T) Calculate the energy flow to the cooling water. Use that value for energy flow to calculate delta T for the exhaust gas using the equation above.
Many missing information : # You have to specify type of that heat exchanger, parallel, cross, or counter flow..... # Specification of the heat exchanger should be given, such as the coefficient of overall heat exchange and heat exchange area before calculation can be performed. For your additional details, you can not calculate the logarithmic mean temperature difference unless you determine all temperatures at inlets and exits. The NTU method must be used to find the missing temperature reading. The above mentioned information specifying the heat exchanger unit must be given beforehand.
