The effect of hot water freezing faster than cold water is mentioned in Greek literature. However, it came out as a scientific phenomenon during the last few decades and is known as Mpemba effect since 1969. But there is an inadequacy of explanation which was a challenge to the modern science. Hence, it is an important issue to revisit this mysterious effect. In this research work it is attempted to justify the Mpemba effect in terms of the heat loss through a number of experiments. A newly introduced technique was used to explore the influence of evaporation on the effect using a thin oil layer. Moreover it was noticed that higher the length of time duration, greater the chance of observing the effect. Finally the Mpemba effect is classified into two, based on cooling curves known as High Cooling Rate (HCR) and Quick Freeze (QF). Then they were analyzed and justified by means of relevant simulations and logical interpretations. Finally it was concluded that the evaporation and nature of ice due to convection current are the main reasons for the effect. A new observation around 4oC is also found in the research.
Full:http://ip-sl.org/procs/2008/ipsl0805.pdf
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