An experimental investigation into heat transfer in milk cooling vessels

Document Type : Article


1 Department of Mechanical Engineering, Sakarya University, Sakarya, Turkey

2 Department of Mechanical Engineering, Sakarya University, Sakarya, Turkey.


The raw milk is an important basic material for many food products. Fresh milk must be cooled immediately after milking to keep high quality and process ability. In this work the overall heat transfer coefficients of the milk cooling vessels used for this purpose have been studied experimentally. This study is aimed to determine the overall heat transfer coefficients of cooling vessels which have different types and capacities without the freezing and churning to avoid separation of milk's fat. Vessels are used ranged as follows: 300-500-1000-1500-1850-2000 litres for verticals and 2000-2500-3000-4000-5000-6000 litres for horizontals. It is found that the theoretical calculations are in satisfactory agreement with the experimental data. As a result of investigation, the overall heat transfer coefficient can be written as related with power intensity for horizontal vessels. It is a certain constant value for vertical ones.


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