73C-22 |
Comparison of uniformity of heating between a helical and a conical heat exchanger |
P. CORONEL and K. P. Sandeep. Food Science Department, North Carolina State University, 39 Schaub Hall, BOX 7624, Raleigh, NC 27695 Several techniques are used in the food industry to enhance the mixing within a fluid and the heat transfer between fluid and particles within heat exchangers and holding tubes. One of the techniques is to use an improved design of heat exchangers, such as the helical heat exchanger. We propose to investigate the use of a novel type of heat exchanger, a conical coil tube heat exchanger. This study was undertaken with the objective of determining the uniformity of processing in a novel type of heat exchanger, the conical heat exchanger, and compare it with other types of heat exchangers (conventional and helical) by conducting experimental and modeling studies. Experiments were conducted in conventional and helical heat exchangers for a range of flow rates and process temperatures (3-10 gpm, 200-300 F). The results of the experiments were compared to the modeling studies performed using a computational fluid dynamics software (CFD-ACE). In addition, mathematical modeling was used to compare the performance of a conical and helical heat exchanger. The results show that a conical heat exchanger can potentially heat a product more rapidly than a helical heat exchanger. The results also provide guidelines for processing different types of products (viscous, particulates) under different processing conditions. The CFD-ACE program proved to be an excellent tool to model heat transfer and fluid flow under several process conditions and for different kinds of heat exchangers. These results could be useful to processors and design engineers to design a conical or helical heat exchanger that would rapidly and uniformly heat their products at the specified process parameters.
Session 73C, Food Engineering: Transport Processes and Kinetics
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