TY - GEN
T1 - Experimental investigation of free convection heat transfer with entrance restriction placed at top of a vertical circular tube
AU - Mohammed, H.
AU - Yusaf, T.
AU - Salman, Y.
PY - 2006
Y1 - 2006
N2 - A free convection from the inside surface of vertical circular tube with a uniformly heated surface (constant wall heat flux) was investigated experimentally for laminar air flow in the ranges of RaL, from 6.9 × 108 to 5 × 109. The effect of restriction lengths placed at top position of the heated tube on the surface temperature distribution and the local and average heat transfer coefficient were studied. The experimental apparatus consists of aluminum tube with 900mm length and 30mm inside diameter. The entry restrictions were included a circular tube of same diameter as the heated tube but with different lengths of 60cm, 90cm, 120cm, 150cm, and 180cm. It was found that the surface temperature along the tube surface higher values for restriction with length of 180cm and smaller values for the restriction with length of 120cm. The results showed that the local Nux and average Nusselt number Nu were higher values for the restriction with length of 120cm and smaller values for the restriction with length of 180cm. The results obtained are correlated by dimensionless groups as LogNuL against Log RaL for each case and proposed a general correlation for all cases.
AB - A free convection from the inside surface of vertical circular tube with a uniformly heated surface (constant wall heat flux) was investigated experimentally for laminar air flow in the ranges of RaL, from 6.9 × 108 to 5 × 109. The effect of restriction lengths placed at top position of the heated tube on the surface temperature distribution and the local and average heat transfer coefficient were studied. The experimental apparatus consists of aluminum tube with 900mm length and 30mm inside diameter. The entry restrictions were included a circular tube of same diameter as the heated tube but with different lengths of 60cm, 90cm, 120cm, 150cm, and 180cm. It was found that the surface temperature along the tube surface higher values for restriction with length of 180cm and smaller values for the restriction with length of 120cm. The results showed that the local Nux and average Nusselt number Nu were higher values for the restriction with length of 120cm and smaller values for the restriction with length of 180cm. The results obtained are correlated by dimensionless groups as LogNuL against Log RaL for each case and proposed a general correlation for all cases.
KW - Entrance restriction top position
KW - Experimental free convection
KW - Vertical circular tube
UR - https://www.scopus.com/pages/publications/33845778046
U2 - 10.1115/esda2006-95229
DO - 10.1115/esda2006-95229
M3 - Conference contribution
AN - SCOPUS:33845778046
SN - 0791837793
SN - 9780791837795
T3 - Proceedings of 8th Biennial ASME Conference on Engineering Systems Design and Analysis, ESDA2006
BT - Proceedings of 8th Biennial ASME Conference on Engineering Systems Design and Analysis, ESDA 2006
PB - American Society of Mechanical Engineers
ER -