The Development of the Computer-Aided Design Software for the Air-Condition and Dehumidfying Finned-Tube Heat Exchangers

• Main Authors: Thong-Chi Liu, 劉榮其
• Other Authors: Jiin-Yuh Jang
• Format: Others
• Language: zh-TW
• Published: 1996
• Online Access: http://ndltd.ncl.edu.tw/handle/89371644016699020534

碩士 === 國立成功大學 === 機械工程研究所 === 84 === There are two parts in this paper . For the first part , annduced wind tunnel was used to measure the heat transfer andressure friction factor for circular finned-tube heat exch- ngers in both dry and wet conditions . The ambient tempera-ure and humidity were controlled at 25 ℃ and 70﹪ . Thexperimental results indicated that the sensible Colburn fac-or was 3~12﹪ higher than the Colburn factor for the dry coilsnd the wet coils friction factor was 2~13﹪ higher than thatf the dry coils . we also developed an equation to predicatehe heat transfer coefficient of wet coils . By comparing with the present experimental data , it wereound that Briggs＆Young''s predications for dry coils wereood agreement with the experimental data . Robinson＆Briggs''redications were higher than the experimental data . Theew correlation of and factors have been developed . The second part of this paper is to develop an interactiveomputer - aided design software for both circular finned-tubend plate finned-tube heat exchangers . In the design logic ,e divided the coils into three cases by comparing the coilsurface temperature and the dew point temperature .1)completely dry : when the outlet dew point temperature is higher than the coils surface temperature .2)partially dry and partially wet : when the inlet dew point temperature is higher than the coils surface temperature and the outlet dew point temperature is lower than the coils surface temperature .3)completely wet : when the inlet dew point temperature is lower than the coils surface temperature .his program was written by Quick BASIC language and can beun in any personal computer . It can solve the rating pro-lem and sizing problem friendly and rapidly . in plate-fin and tube heat exchangers.of