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Are these statements about the heat exchangerstrue? Statement 1: In parallel flow, the temperature difference between the two fluids is large at the entrance end, but it becomes small at the exit end. Statement 2: The log mean temperature difference is greater for parallel flow.

Are these statements about the heat exchangerstrue? Statement 1: In parallel flow, the temperature difference between the two fluids is large at the entrance end, but it becomes small at the exit end. Statement 2: The log mean temperature difference is greater for parallel flow. Correct Answer True, False

In parallel flow, both the fluids enter at one end and exit at the other end.the temperature difference between the two fluids is large at the entrance end, but it becomes small at the exit end. The log mean temperature difference is greater for counter flow. So the surface area of the parallel flow heat exchanger should be larger than for a counter flow heat exchanger.

Related Questions

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Directions : Following question consists of a statement followed by three arguments I, II and III . You have to decide which of the arguments is a STRONG arguments and which is a WEAK Argument.

Statement : Should admission to all professional courses be made on the basis of past academic performance rather than through entrance tests?

Arguments :
I. Yes. It will be beneficial for those candidates who are unable to bear the expenses of entrance tests.
II. Yes. Many deserving candidates securing high marks in their qualifying academic examinations do not perform well on such entrance tests.
III. No. The standard of examinations and assessment conducted by different Boards and universities are not comparable and hence there is a need to conduct entrance tests to calibrate them on a common yardstick.
The logarithmic mean temperature difference ($${{\text{t}}_{\text{m}}}$$) is given by (where $$\Delta {{\text{t}}_1}$$ and $$\Delta {{\text{t}}_2}$$ are temperature differences between the hot and cold fluids at entrance and exit)