scholarly journals Thermo-Hydraulic Performance Evaluation of Shell & Tube Heat Exchanger with Different Tube Geometries

2019 ◽  
Vol 9 (1) ◽  
pp. 2125-2132
Keyword(s):  
Heat Exchanger ◽  
Cross Sections ◽  
Heat Exchangers ◽  
Power Plants ◽  
Waste Heat ◽  
Flow Behavior ◽  
Hydraulic Performance ◽  
Fluid Stream ◽  
Ansys Fluent ◽  
Tube Heat Exchanger

A heat exchanger is equipment that transfers heat energy from one fluid stream to another fluid stream across a solid surface by conduction and convection. Heat exchangers are used in air conditioning & refrigeration systems, power plants, automotive industries, chemical processing, waste heat recovery systems, and food industries. Shell & tube heat exchangers are the most widely used heat exchanger. Earlier many types of studies were carried out on baffle of heat exchanger, as the hydraulic performance of shell side of exchanger relies on baffle elements such as changing baffle types, baffle segments, baffle angles, baffle cuts, etc. are introduced. But only a few researches are concentrated on the tube side. In this paper, efforts have been made to design a shell & tube heat exchanger by using the kern method & referring TEMA standards. Also, the fluid flow behavior & heat transfer mechanism of shell & tube heat exchanger with four different cross-sections of the tubes i.e. Circular, Rectangular, Square & Triangular is numerically investigated using ANSYS-fluent. Numerical simulation was carried out for a single tube pass shell & tube heat exchanger with 25% baffle cut. Finally, from the simulation results, suggestions are made for the best geometry which gives the best thermo-hydraulic performance

Impact of an Anisotropic Fin Surface Design on the Thermal-Hydraulic Performance of a Plain-Fin-and-Tube Heat Exchanger

2011 ◽  
Author(s):  
Rong Yu ◽  
Andrew D. Sommers ◽  
Nicole C. Okamoto ◽  
Koushik Upadhyayula
Keyword(s):  
Heat Transfer ◽  
Heat Exchanger ◽  
Pressure Drop ◽  
Heat Exchangers ◽  
Hydraulic Performance ◽  
Normal Operation ◽  
Surface Design ◽  
Tube Heat Exchanger ◽  
Silane Coating ◽  
Side Pressure

In this study, we have explored the effectiveness of heat exchangers constructed using anisotropic, micro-patterned aluminum fins to more completely drain the condensate that forms on the heat transfer surface during normal operation with the aim of improving the thermal-hydraulic performance of the heat exchanger. This study presents and critically evaluates the efficacy of full-scale heat exchangers constructed from these micro-grooved surfaces by measuring dry/wet air-side pressure drop and dry/wet air-side heat transfer data. The new fin surface design was shown to decrease the core pressure drop of the heat exchanger during wet operation from 9.3% to 52.7%. Furthermore, these prototype fin surfaces were shown to have a negligible effect on the heat transfer coefficient under both dry and wet conditions while at the same time reducing the wet airside pressure drop thereby decreasing fan power consumption. That is to say, this novel fin surface design has shown the ability, through improved condensate management, to enhance the thermal-hydraulic performance of plain-fin-and-tube heat exchangers used in air-conditioning applications. This paper also presents data pertaining to the durability of the alkyl silane coating.

Performance Evaluation of Multi-Stage Shell and Tube Transport Membrane Condenser Heat Exchangers for Low Grade Waste Heat and Water Recovery

2017 ◽  
Author(s):  
Soheil Soleimanikutanaei ◽  
Cheng-Xian Lin ◽  
Dexin Wang
Keyword(s):  
Water Vapor ◽  
Heat Exchanger ◽  
Heat Exchangers ◽  
Power Plants ◽  
Ceramic Membrane ◽  
Waste Heat ◽  
Low Grade ◽  
Water Recovery ◽  
Multi Stage ◽  
Shell And Tube

In this work for the first time the performance of multi-stage shell and tube Transport Membrane Condenser (TMC) based heat exchangers are evaluated numerically. The present heat exchanger is design to work under high pressure and temperature condition for both heat and water recovery in Oxy-Combustion processes. TMC heat exchangers use the nano-porous and ceramic membrane technology to extract the water vapor and latent heat of condensation from the flue-gas. The most important application of TMC heat exchangers is in the power plants which the water vapor in the presence of other non-condensable gases (i.e. CO2, O2 and N2) exist. Effect of the different arrangement of the multi-stage shell and tube TMC heat exchangers, number of branches and number of heat exchangers in each branch on the heat transfer and water recovery have been studied numerically. A single phase multi-component model is used to assess the capability of single stage TMC heat exchangers in terms of waste heat and water recovery at various inlet conditions. Numerical simulation has been performed using ANSYS-FLUENT software and the condensation rate model has been implemented applying User Define Function. Finally, an optimum configuration for the TMC heat exchanger unit has been proposed and the results of numerical simulations are depicted in terms of temperature and water vapor mass fraction contours.

scholarly journals CFD ANALYSIS OF HEAT EXCHANGER MODELS DESIGN USING ANSYS FLUENT

2020 ◽  
Author(s):  
Ram Kishan ◽  
Devendra Singh ◽  
Ajay Kumar Sharma
Keyword(s):  
Temperature Field ◽  
Heat Exchanger ◽  
Heat Exchangers ◽  
Extreme Temperature ◽  
Cfd Analysis ◽  
Ansys Fluent ◽  
Tube Heat Exchanger ◽  
Programming Tool ◽  
Best Parameter ◽  
Is Design

The aim of the study is design tube and box heat exchanger with various pattern of tubes and examine the flow and temperature field at inlet and outlet point of tube and container using ANSYS programming tool. Three types of heat exchangers are planned in this examination with various structures of cylinders contains of 175 mm breadth and 1000 mm length shell measurement 175 mm. To expand the rate of heat exchange of heat exchanger advancement is done which tries to distinguish the best parameter combination of heat exchangers. The prefix parameter (tube width) is utilized as an info variable and the yield parameter is the most extreme temperature distinction of container and tube heat exchanger. Three types models are design on the basis tubes varieties of heat exchanger and CFX examination is completed in ANSYS 14.0.

scholarly journals Numerical Simulation of Shell and Tube Heat Exchanger using Ansys Fluent

2019 ◽  
Vol 8 (11S2) ◽  
pp. 543-545
Keyword(s):  
Heat Exchanger ◽  
Heat Exchangers ◽  
Cooling System ◽  
Hot Water ◽  
Hydraulic Power ◽  
Ansys Fluent ◽  
Tube Heat Exchanger ◽  
Desirable Outcome ◽  
Computational Fluid Dynamics Cfd ◽  
Shell And Tube

From the current situation, the Heat Exchangers uses extreme commonly are tube and Shell heat exchangers. The most usual uses of Shell and tube heat exchangers are electricity creation, cooling system of hydraulic fluid, oil in motors, transmissions, and hydraulic power packs. Shell and tube heat exchangers are made of the casing using a bunch of tubes with inside. The desirable outcome of the paper is to figure out the speed of heat transport using hot water as the hot liquid. The target of this paper is to mimic a tube and shell heat exchanger and also to assess blood flow and temperatures from the tubes and shell by employing applications tool Ansys. The simulation is composed of modeling and meshing cross section of tube and shell heat exchanger utilizing computational fluid dynamics (CFD).

Numerical Study of Flow Deflection and Horseshoe Vortices in a Louvered Fin Round Tube Heat Exchanger

2012 ◽  
Vol 134 (9) ◽  
Author(s):  
H. Huisseune ◽  
C. T’Joen ◽  
P. De Jaeger ◽  
B. Ameel ◽  
J. Demuynck ◽  
...  
Keyword(s):  
Heat Exchanger ◽  
Heat Exchangers ◽  
Flow Behavior ◽  
Three Dimensional ◽  
Horseshoe Vortex ◽  
Two Dimensional ◽  
Round Tube ◽  
Tube Heat Exchanger ◽  
Louvered Fin ◽  
Flow Deflection

In louvered fin heat exchangers, the flow deflection influences the heat transfer rate and pressure drop and thus the heat exchanger’s performance. To date, studies of the flow deflection are two-dimensional, which is an acceptable approximation for flat tube heat exchangers (typical for automotive applications). However, in louvered fin heat exchangers with round tubes, which are commonly used in air-conditioning devices and heat pumps, the flow is three-dimensional throughout the whole heat exchanger. In this study, three-dimensional numerical simulations were performed to investigate the flow deflection and horseshoe vortex development in a louvered fin round tube heat exchanger with three tube rows in a staggered layout. The numerical simulations were validated against the experimental data. It was found that the flow deflection is affected by the tubes in the same tube row (intratube row effect) and by the tubes in the upstream tube rows (intertube row effect). Flow efficiency values obtained with two-dimensional studies are representative only for the flow behavior in the first tube row of a staggered louvered fin heat exchanger with round tubes. The flow behavior in the louvered elements of the subsequent tube rows differs strongly due to its three-dimensional nature. Furthermore, it was found that the flow deflection affects the local pressure distributions upstream of the tubes of the downstream tube rows and thus the horseshoe vortex development at these locations. The results of this study are important because the flow behavior is related to the thermal hydraulic performance of the heat exchanger.

Shape optimization of segmental porous baffles for enhanced thermo-hydraulic performance of shell-and-tube heat exchanger

2020 ◽  
Vol 180 ◽  
pp. 115835 ◽  
Author(s):  
Hamid Reza Abbasi ◽  
Ebrahim Sharifi Sedeh ◽  
Hossein Pourrahmani ◽  
Mohammad Hadi Mohammadi
Keyword(s):  
Heat Exchanger ◽  
Shape Optimization ◽  
Hydraulic Performance ◽  
Tube Heat Exchanger ◽  
Shell And Tube

Analysis of the Thermal Stress at the Tubesheet in Floating-Head or U-Tube Heat Exchangers

2017 ◽  
Vol 139 (2) ◽  
Author(s):  
Jiuyi Liu ◽  
Caifu Qian ◽  
Huifang Li
Keyword(s):  
Thermal Stress ◽  
Heat Exchanger ◽  
Temperature Difference ◽  
Heat Exchangers ◽  
Influence Factors ◽  
Area Ratio ◽  
Shell Side ◽  
Tube Heat Exchanger ◽  
Numerical Tests ◽  
Hole Area

Thermal stress is an important factor influencing the strength of a heat exchanger tubesheet. Some studies have indicated that, even in floating-head or U-tube heat exchangers, the thermal stress at the tubesheet is significant in magnitude. For exploring the value, distribution, and the influence factors of the thermal stress at the tubesheet of these kind heat exchangers, a tubesheet and triangle arranged tubes with the tube diameter of 25 mm were numerically analyzed. Specifically, the thermal stress at the tubesheet center is concentrated and analyzed with changing different parameters of the tubesheet, such as the temperature difference between tube-side and shell-side fluids, tubesheet diameter, thickness, and the tube-hole area ratio. It is found that the thermal stress of the tubesheet of floating-head or U-tube heat exchanger was comparable in magnitude with that produced by pressures, and the distribution of the thermal stress depends on the tube-hole area and the temperature inside the tubes. The thermal stress at the center of the tubesheet surface is high when tube-hole area ratio is very low. And with increasing the tube-hole area ratio, the stress first decreases rapidly and then increases linearly. A formula was numerically fitted for calculating the thermal stress at the tubesheet surface center which may be useful for the strength design of the tubesheet of floating-head or U-tube heat exchangers when considering the thermal stress. Numerical tests show that the fitted formula can meet the accuracy requirements for engineering applications.

Development of Heat Exchanger Fouling Model and Preventive Maintenance Diagnostic Tool

2007 ◽  
Vol 2 (2) ◽  
Author(s):  
H. Zabiri ◽  
V. R. Radhakrishnan ◽  
M. Ramasamy ◽  
N. M. Ramli ◽  
V. Do Thanh ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Heat Exchanger ◽  
Predictive Model ◽  
Diagnostic Tool ◽  
Preventive Maintenance ◽  
Heat Exchangers ◽  
Waste Heat ◽  
A Priori ◽  
Transfer Efficiency ◽  
Heat Transfer Efficiency

The Crude Preheat Train (CPT) is a set of large heat exchangers which recover the waste heat from product streams back to preheat the crude oil. The overall heat transfer coefficient in these heat exchangers may be significantly reduced due to fouling. One of the major impacts of fouling in CPT operation is the reduced heat transfer efficiency. The objective of this paper is to develop a predictive model using statistical methods which can a priori predict the rate of the fouling and the decrease in heat transfer efficiency in a heat exchanger in a crude preheat train. This predictive model will then be integrated into a preventive maintenance diagnostic tool to plan the cleaning of the heat exchanger to remove the fouling and bring back the heat exchanger efficiency to their peak values. The fouling model was developed using historical plant operating data and is based on Neural Network. Results show that the predictive model is able to predict the shell and tube outlet temperatures with excellent accuracy, where the Root Mean Square Error (RMSE) obtained is less than 1%, correlation coefficient R2 of approximately 0.98 and Correct Directional Change (CDC) values of more than 90%. A preliminary case study shows promising indication that the predictive model may be integrated into a preventive maintenance scheduling for the heat exchanger cleaning.

Sign in / Sign up

Export Citation Format

Share Document