Heat transfer and flow resistance performance of shutter baffle heat exchanger with triangle tube layout in shell side

AbstractHeat exchangers possess a significant role in energy transmission and energy generation in most industries. In this work, a three-dimensional simulation has been carried out of a shell and tube heat exchanger (STHX) consisting of segmental baffles. The investigation involves using the commercial code of ANSYS CFX, which incorporates the modeling, meshing, and usage of the Finite Element Method to yield numerical results. Much work is available in the literature regarding the effect of baffle cut and baffle spacing as two different entities, but some uncertainty pertains when we discuss the combination of these two parameters. This study aims to find an appropriate mix of baffle cut and baffle spacing for the efficient functioning of a shell and tube heat exchanger. Two parameters are tested: the baffle cuts at 30, 35, 40% of the shell-inside diameter, and the baffle spacing’s to fit 6,8,10 baffles within the heat exchanger. The numerical results showed the role of the studied parameters on the shell side heat transfer coefficient and the pressure drop in the shell and tube heat exchanger. The investigation shows an increase in the shell side heat transfer coefficient of 13.13% when going from 6 to 8 baffle configuration and a 23.10% acclivity for the change of six baffles to 10, for a specific baffle cut. Evidence also shows a rise in the pressure drop with an increase in the baffle spacing from the ranges of 44–46.79%, which can be controlled by managing the baffle cut provided.

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Investigation of Heat Transfer for Shell-Tube Fuel-Cooled Heat Exchanger

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.378.459 ◽

2013 ◽

Vol 378 ◽

pp. 459-465

Author(s):

Ya Guo Lu ◽

Peng Fei Zhu

Keyword(s):

Heat Transfer ◽

Heat Exchanger ◽

Relative Error ◽

Absolute Error ◽

Heat Transfer Characteristics ◽

Shell Side ◽

Transfer Characteristics ◽

Aero Engine ◽

The Absolute

A calculate method based on ε-NTU model for heat transfer characteristics of shell-tube fuel-cooled heat exchanger of aero-engine lubrication system was built. The heat convection coefficient was obtained by a dimensionless curve (Re~StPr2/3), which was detailed introduced as well. A case study was executed at last. The absolute error of the outlet lubrication of the tube side and the shell side between the value of calculation and experiment was less than ±10°C, and the relative error was less than 6.5%. The absolute error of the heat transferred between calculation and experiment was less than ±0.9kW, and the relative error was less than 7.4%. It indicates that the mothod is available for the investigation of heat transfer characteristics of shell-tube fuel-cooled heat exchanger.

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Performance Analysis and Design Optimization of Shell and Tube Heat Exchangers

10.21203/rs.3.rs-407371/v1 ◽

2021 ◽

Author(s):

praveen math

Keyword(s):

Heat Transfer ◽

Heat Exchanger ◽

Heat Exchangers ◽

Pressure Loss ◽

Fluid Flows ◽

Hot Water ◽

Flow Conditions ◽

Shell Side ◽

Shell And Tube ◽

Side Flow

Abstract Shell and Tube heat exchangers are having special importance in boilers, oil coolers, condensers, pre-heaters. They are also widely used in process applications as well as the refrigeration and air conditioning industry. The robustness and medium weighted shape of Shell and Tube heat exchangers make them well suited for high pressure operations. The aim of this study is to experiment, validate and to provide design suggestion to optimize the shell and tube heat exchanger (STHE). The heat exchanger is made of acrylic material with 2 baffles and 7 tubes made of stainless steel. Hot fluid flows inside the tube and cold fluid flows over the tube in the shell. 4 K-type thermocouples were used to read the hot and cold fluids inlet and outlet temperatures. Experiments were carried out for various combinations of hot and cold water flow rates with different hot water inlet temperatures. The flow conditions are limited to the lab size model of the experimental setup. A commercial CFD code was used to study the thermal and hydraulic flow field inside the shell and tubes. CFD methodology is developed to appropriately represent the flow physics and the procedure is validated with the experimental results. Turbulent flow in tube side is observed for all flow conditions, while the shell side has laminar flow except for extreme hot water temperatures. Hence transition k-kl-omega model was used to predict the flow better for transition cases. Realizable k- epsilon model with non-equilibrium wall function was used for turbulent cases. Temperature and velocity profiles are examined in detail and observed that the flow remains almost uniform to the tubes thus limiting heat transfer. Approximately 2/3 rd of the shell side flow does not surround the tubes due to biased flow contributing to reduced overall heat transfer and increased pressure loss. On the basis of these findings an attempt has been made to enhance the heat transfer by inducing turbulence in the shel l side flow. The two baffles were rotated in opposite direction to each other to achieve more circulation in the shell side flow and provide more contact with tube surface. Various positions of the baffles were simulated and studied using CFD analysis and th e results are summarized with respect to heat transfer and pressure loss.

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Performance Study of Heat Exchangers with Continuous Helical Baffles on Different Inclination Angles

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.655-657.461 ◽

2013 ◽

Vol 655-657 ◽

pp. 461-464 ◽

Cited By ~ 1

Author(s):

Su Fang Song

Keyword(s):

Heat Transfer ◽

Heat Transfer Coefficient ◽

Heat Exchanger ◽

Pressure Drop ◽

Transfer Coefficient ◽

Heat Exchangers ◽

Performance Study ◽

Three Dimensional Model ◽

Shell Side ◽

Inclination Angles

The three-dimensional model of heat exchangers with continuous helical baffles was built. The fluid flow dynamics and heat transfer of shell side in the helical baffled heat exchanger were simulated and calculated. The velocity, pressure and temperature distributions were achieved. The simulation shows that with the same baffle pitch, shell-side heat transfer coefficient increased by 25% and the pressure drop decreases by 18% in helical baffled heat exchanger compared with segmental helical baffles. With the analyzing of the flow and heat transfer in heat exchanger in 5 different inclination angles from 11°to 21°, it can be found that both shell side heat transfer coefficient and pressure drop will reduce respectively by 86% and 52% with the increases 11°to 21°of the inclination angles. Numerical simulation provided reliable theoretical reference for further engineering research of heat exchanger with helical baffles.

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