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Performance Analysis of the Soft Ice-cream Maker Having Two Evaporators Operating at Different Temperatures

두개의 증발기가 장착된 소프트 아이스크림 제조기의 성능 해석

  • Kim, Jeong-Sik (Division of Technical Innovation, Incheon Technopark) ;
  • Kim, Nae-Hyun (Department of Mechanical Engineering, University of Incheon)
  • 김정식 ((재)인천테크노파크 기술혁신본부) ;
  • 김내현 (인천대학교 기계공학과)
  • Received : 2012.11.06
  • Accepted : 2013.02.06
  • Published : 2013.02.28

Abstract

Small size ice-cream maker has two evaporators having different evaporating temperatures of $4^{\circ}C$ and $-8^{\circ}C$. In such case, ice-cream maker system design becomes complicated because multiple capillary tubes affects one another. In this study, performance analysis was conducted for the soft ice-cream maker having two evaporators operating at different temperatures. The compressor was analyzed using efficiency models, the capillary tube was modeled assuming one-dimensional flow, the condenser and the evaporators were modeld based on UA-LMTD method. The refrigeration cycle simulation program was developed applying the enthalpy, pressure and mass balance on each component. Comparison of the test data with the simulated results for R404A revealed that evaporator temperatures of refrigerator and freezer agreed within $3^{\circ}C$.

아이스크림제조기는 원액통과 냉각통의 증발온도가 $4^{\circ}C$$-8^{\circ}C$로 각각 다르므로 다수의 모세관을 이용하는데 이 경우 서로 냉매 유량에 영향을 주므로 냉동사이클 설계가 복잡하다. 본 연구에서는 증발온도가 서로 다른 두개의 증발기(냉장 및 냉동)가 장착된 소프트 아이스크림 제조기의 성능을 해석하였다. 압축기 해석에는 효율모델을 적용하였고, 모세관은 1차원 유동으로 간주하여 해석하였으며, 응축기와 증발기는 UA-LMTD법을 적용하여 해석하였다. 요소부품에서의 엔탈피, 압력 및 질량의 평형을 적용하여 냉동사이클 시뮬레이션 프로그램을 개발하였고 R404A를 사용하는 아이스크림 제조기에 적용한 결과, 냉장과 냉동 증발기의 온도를 $3^{\circ}C$ 이내로 예측하여 측정치와 대체로 일치하였다.

Keywords

References

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