| Title |
Convective Boiling Two-phase Flow in Trapezoidal Microchannels：Part 1-Pressure Drop Characteristics |
| Authors |
김병주(Byong Joo Kim) ; 김건일(Geonil Kim) |
| Keywords |
2상유동 압력강하 ; 미세유로 ; 2상 마찰배수 ; 마티넬리 변수 ; 치숄름 변수 Two-phase flow pressure drop ; Microchannels ; Twophase friction multiplier ; Martinelli parameter ; Chisholm parameter |
| Abstract |
Characteristics of two-phase pressure drop in microchannels were investigated experimentally. The microchannels consisted of 9 parallel trapezoidal channels with each channel having 205㎛ of bottom width, 800㎛ of depth, 3.6° of sidewall angle, and 7 cm of length. Pressure drops in convective boiling of Refrigerant 113 were measured in the range of inlet pressure 105～195 kPa, mass velocity 150～920 kg/㎡s, and heat flux 10～100 kW/㎡. The total pressure drop generally increased with increasing mass velocity and/or heat flux. Two-phase frictional pressure drop across the microchannels increased rapidly with exit quality and showed bigger gradient at higher mass velocity. A critical review of correlations in the literature suggested that existing correlations were not able to match the experimental results obtained for two-phase pressure drop associated with convective boiling in microchannels. A new correlation suitable for predicting two-phase friction multiplier was developed based on the separated flow model and showed good agreement with the experimental data. |