An advanced turbulator with blades and semi-conical section for heat transfer improvement in a helical double tube heat exchanger  

一种改进螺旋双管换热器传热性能的叶片半圆锥形紊流器

作　　者：Seyed Hossein HASHEMI KAROUEI Seyed Soheil MOUSAVI AJAROSTAGHI Saman RASHIDI Elham HOSSEINIRAD 

机构地区：[1]Department of Mechanical Engineering,Babol Noshirvani University of Technology,Babol,Mazandaran,Iran [2]Department of Energy,Faculty of New Science and Technologies,Semnan University,Semnan,Iran [3]Department of Chemical,Petroleum,and Gas Engineering,Semnan University,Semnan,Iran

出　　处：《Journal of Central South University》2021年第11期3491-3506,共16页中南大学学报（英文版）

摘　　要：In present work,a helical double tube heat exchanger is proposed in which an advanced turbulator with blades,semi-conical part,and two holes is inserted in inner section.Two geometrical parameters,including angle of turbulator’s blades(θ) and number of turbulator’s blades(N),are considered.Results indicated that firstly,the best thermal stratification is achieved at θ=180°.Furthermore,at the lowest studied mass flow rate(m = 8 × 10^(-3) kg/s),heat transfer coefficient of turbulator with blade angle of 180° is 130.77%,25%,and 36.36% higher than cases including without turbulator,with turbulator with blade angle of θ =240°,and θ =360°,respectively.Moreover,case with N=12 showed the highest overall performance.At the highest studied mass flow rate(m = 5.842 × 10^(-2) kg/s),heat transfer coefficient for case with N=12 is up to 54.76%,27.45%,and 6.56% higher than cases including without turbulator,with turbulator with N=6,and with turbulator with N=9,respectively.本文提出了一种内部具有叶片及半圆锥形双孔紊流器的螺旋双管换热器。研究了紊流叶片角θ和紊流叶片数N对传热性能的影响。结果表明:热分层在θ=180°时达到最佳;在最小质量流率(m=8×10^(-3)kg/s)条件下,叶片倾角为180°的紊流器的换热系数比不含紊流器、及叶片倾角为240°和360°的紊流器分别高130.77%、25%和36.36%。N=12的综合性能表现最好。在最大质量流率下(m=5.842×10^(-2)kg/s),N=12时的换热系数比无紊流器、叶片数为6和9时的换热系数分别提高了54.76%、27.45%和6.56%。

关 键 词：helical double tube heat exchanger TURBULATOR BLADE thermal performance swirl flows 

分 类 号：TK172[动力工程及工程热物理—热能工程]