| A new process of intensifying heat transfer by placing several sections of short specially forged tube with twisted slices was experimentally studied and analog computed in the thesis.The experimental results showed that in central area U/Uav of high Re was less than it of lower Re and axial velocity distributing was smoother than it in circinal tube, while in near wall area,U/Uav of high Re was bigger than it of lower Re and velocity grads was bigger than it in circinal tube.ΔP in tube increased while forged tube with twisted slice was installed, whereas pressure distributing was still even along the direction of tubal lengh for the whole tube.The effects of forged tube with twisted slice on TMT of cracking furnace, outlet temperature of TLE, and the yield of ethylene at different condition of naphtha cracked were discussed．The results showed that TMT decreased by 20℃more, the yield of leading product changed less, outlet temperature of TLE was lower and the variational trend of it was smooth.Based on gridding partition, the calculated area of forged tube with twisted slice was partitioned. By this means the optimal y and the relationship between f and Re were obtained. Theoretical predictions agreed well with the experimental results. twisted slice,cracking furnace,ethylene,analog computation,intensified heat transfer...
|
PDF Full Text Request