Optimization of the Scraper Speed and Improvement of the Refrigerant Path for the Evaporator of the Soft Ice Cream Machine

소프트 아이스크림 제조기 증발기의 스크레이퍼 회전수 최적화 및 냉매 유로 개선

  • Baek, Seung-Hyuk (Department of Mechanical Engineering, Incheon National University) ;
  • Kim, Nae-Hyun (Department of Mechanical Engineering, Incheon National University)
  • Received : 2017.09.05
  • Accepted : 2017.10.13
  • Published : 2017.10.31


Improvements in the standard of living and lifestyle have led to increased sales of frozen milk products, such as soft ice cream or slush. These frozen milk products are commonly made in a small refrigeration machine. In a soft ice cream machine, the freezer is composed of a concentric cylinder, where the refrigerant flows in the annul us and the ice cream is made in the cylinder by a rotating scraper. In this study, an optimization and performance evaluation were conducted on a soft ice cream machine having a freezer volume of 2.8 liters. The optimization was focused on the scraper rotation speed and the refrigerant path of the freezer. The measurements included the temperature, pressure and consumed power. At the optimized speed of 124 rpm, ice cream was produced in 6 minutes and 2 seconds, and the COP was 0.90. Through a flow visualization study using air-water, the refrigerant path was improved. The improved design reduced the ice cream making time significantly. The present results may be used for the optimization of other refrigeration cycles, including those of frozen food products.


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