Temperature Difference Compensation Analysis Of External Guide Shell On Heat Exchanger

Heat exchanger is a kind of energy-saving equipments which can transfer heat between materials, and it is usually applied in the industries of petroleum, chemistry, metallurgy, electricity and food as well as in the light industry. Along with the rapid development of energy conservation technology, heat exchanger is applied in more fields and has brought about remarkable economic benefits. Among all kinds of heat exchangers, shell and tube heat exchanger is applied mostly . Meanwhile, as the size of the petrochemical equipments is getting larger and larger, heat exchanger with external guide shell is applied more prevalently.Based on the ordinary model of shell and tube heat exchanger, external guide shell heat exchanger has a newly-improved structure on the shell. Generally speaking, external guide shell consists of the following five parts: big cylindrical shell, positive annulated shell, conical shell, negative annulated shell and small cylindrical shells. This kind of structure can make the liquid run through the duct more equably, enlarge the area of heat diffusion, improve the heat-transferring efficiency of the heat interchanger, decrease the power consumption and prevent the liquid's impact on the tubes at the entrance to slow down the damage.Except for the advantages mentioned hereinbefore, external guide shell possesses more functions such as temperature compensation and prestressed. Based on the ANSYS analyzing software, this thesis is to analyze the temperature field and the structure of external guide shell heat exchanger and to validate its ability to temperature compensation. With the fruits of predecessors, this thesis aims at studying and designing a new model of external guide shell heat exchanger which can be prestressed. The study mainly includes:1. to build up an entity model with external guide shell and without external guide shell by Pro/E software, then input the information to ANSYS in order to build up the analyzing model;2. to use the ANSYS analyzing software to analyze the temperature field of the heat interchanger as well as the therm—struc coupling of both heat interchanger with external guide shell and without external guide shell, to prove external guide shell's ability to temperature compensation;3. to compare the thermal stresses of conical Shell in different half top angle and annulated shell in different radius, so as to decide the factors which influence the distribution of the stress of external guide shell heat exchanger;4. to verify the reliability of the results of this experiment by comparing it to the studies of predecessors;5. to design a prestressed heat interchanger with external guide shell, analyze its thermal stresses, therefore verify the rationality and practicability of the prestressed heat exchanger with external guide shell.The final result shows that the thermoelectric stress will be reduced by 20% to 30% if the heat interchanger is equipped with a external guide shell, and its ability to equalize the temperature will be enhanced as the half top angle of the conical Shell gets bigger. Meanwhile, as the heat interchanger is equipped with external guide shell, it's shell becomes softer, as a result preload can be placed on the shell to create a prestress heat interchanger with a external guide shell, which can decrease the thermoelectric stress of the heat interchanger and make the machine stay in a low-stress condition. This kind of multi-functional external guide shell is of certain reference value to the design of heat interchanger.