For the purpose of the enhancement of the air conditioner performance and fuel effciency, several cases of centrifugal impeller for passenger car air conditioner have been numerically analyzed by changing central angle of blades and length of outlet for shape optimization of the impeller. Commercial CFD program Fluent 6.3.26 has been used to compute velocity, temperature, pressure and turbulence intensity that can lead numerous results. The central angles of two blades and three cases of outlet length led 4～12% and 3.5～6.4% differences of velocity and flow rate, respectively. The velocity distribution near the blade surface was axisymmetric and had a maximum value of 22.19 m/s and velocity of the vertical direction of the impeller showed linear increase with horizontal direction. At case 3 of oultet length, there existed a a minimum pressure value of -133320 Pa.

Abstract
 1. 서론
 2. 유동해석 방법
  2.1 설계 조건
  2.2 격자 생성
 3. 결과 및 고찰
 4. 결론
 참고문헌

• 이동렬(대구가톨릭대학교 기계자동차공학부) | Dong-Ryul Lee