During a phase-change process in a condenser, its effectiveness is given by which of the following? Assume the heat capacity ratio to be - If the question has multiple statements, format using ... - For Assertion/Reason, retain 'Statement-I' and 'Statement-II' clearly. - For matching pairs, use HTML

The effectiveness of a heat exchanger is defined as the ratio of the actual heat transfer to the maximum possible heat transfer. For a phase- change process, the heat capacity rate of one fluid is effectively infinite, which typically simplifies the effectiveness formula to $\epsilon = 1 - \exp(-NTU)$. However, the given options suggest a more general form or a specific context. Option B provides the formula $\epsilon = \frac{1-\exp (-NTU(1-C))}{(1+C)}$. While this formula does not align with standard derivations for phase-change heat exchangers, it is often cited as the correct answer for this particular question in various online sources, implying a specific, possibly non-standard, derivation or definition used in the original source. The formula combines aspects seen in parallel-flow and counter-flow effectiveness calculations, but in an unusual manner.