The small catamaran leisure boat which is 4.1m length, 1.9m breadth and 0.7 ton displacement was designed. To decide optimum breadth, four sets of distances between hulls were considered. CFD analysis using FLUENT was performed to examine flow patterns, pressure distribution and wave height between two hulls. Model test at CWC in INHA Technical College was also carried out to get the resistance for final hull form at design speed 5 knots. The feature of flow pattern among four different distances between hulls were compared and discussed. The optimum breadth of design vessel was decided depending on the CFD results and comments of expertise that has experience on board the small demihull. The design procedure to choose optimum breadth, especially small change of the hull distance, using CFD was described in this paper

Abstract
 1. 서론
 2. 초기 선형
 3. 수치 해석
  3. 1 계산 대상 및 방법
  3. 2 계산 결과
 4. 모형 시험 및 결과 해석
 5. 결론
 참고문헌

• 김현수(인하공업전문대학 선박해양시스템과) | K. H. SOO
• 정우철(인하공업전문대학) | ․J. U. CHEOL