| Plate heat exchanger is widely used in all walks of life are inseparable from the application of heat exchanger,in the case of unilateral flow,due to the import and export of plate heat exchanger is located in the same side up and down,close to the import and export of attachment when the direction of fluid flow path is shorter,the resistance is small,make the velocity faster,import and export attachment direction of fluid flow away from far,resistance is bigger,makes the flow velocity is slow,which makes the fluid flow distribution is not uniform,on entering the change hotspot this affects hot and cold fluid heat transfer.In this paper,through the establishment of a complete plate heat exchanger double shape plate,and then the Solid Works software to extract its cold side fluid domain for numerical simulation research,analysis of the velocity field,temperature field,pressure field and study the heat exchange zone inlet and outlet side of the velocity of the section.It is found that in the case of single flow in plate heat exchanger,the flow distribution is still uneven after the fluid flows through the diversion zone.The velocity of the section near the inlet and outlet connection direction is larger,while the velocity of the section far away from the inlet and outlet connection direction is smaller.By comparing the velocity distribution at the inlet and outlet sides of the heat exchange zone,it is found that the velocity distribution at the outlet side is slightly more uniform than that at the inlet side after the fluid passes through the turbulence of the two-shaped corrugated plate in the heat exchange zone,but there is still uneven flow distribution phenomenon,and the degree of unevenness increases with the increase of Reynolds number.By changing the three structural parameters of the diversion zone,the flow distribution problem in the fluid domain and the enhanced heat transfer characteristics were studied.When the Reynolds number is in the range of 2488-12440,changing the Angle of the upper side of the diversion zone has a certain influence on the flow distribution and heat transfer enhancement.When the Angle is 60 degrees,the flow distribution is more uniform,and the amplitude of the maximum unevenness and the comprehensive unevenness of the flow are0.572 and 0.131,which are 34.9% and 5.7% lower than the original model.Compared with the original model,the Nussel number increases by 5.2%,and the resistance factor increases by 11.4%.The change of the bottom space of the diversion area has a certain influence on the flow distribution.Under the condition of 60 degrees of diversion area angle,the flow distribution is more uniform when the distance is 15 mm,the amplitude of the maximum unevenness and the comprehensive unevenness of the flow are 0.522 and 0.122,which are40.5% and 12.23% lower than the original model;.Changing the Angle of the lower left channel of the diversion zone has a certain influence on the flow distribution and enhancement.Under the premise of 60 degrees of the diversion zone Angle,the flow distribution is more uniform when the Angle of the lower left is 180 degrees.The maximum unevenness rate and the amplitude of comprehensive flow unevenness are 0.397 and 0.100,which are reduced by 54.8% and 28.1% compared with the original model.Compared with the original model,the Nussel number increases by 7.9%,and the resistance factor increases by 11.6%.The flow distribution and enhanced heat transfer characteristics in the fluid domain were studied in the form of sealing strips.It was found that sealing strips had a certain influence on flow distribution and enhancement when the Reynolds number was in the range of2488-12440.Three sealing strips had the best effect,and the amplitude of maximum unevenness and comprehensive flow unevenness were 0.612 and 0.108,which were reduced by 30.3% and 22.3% compared with the original model.Compared with the original model,the Nussel number increases by 9.8%,and the resistance factor increases by the most by17.6%. |
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