Triple Heat Exchanger, CFD Simulation Ansys Fluent Training

An in-depth computational fluid dynamics analysis of a triple concentric tube heat exchanger, exploring the complex thermal interactions between three fluid streams flowing through concentrically arranged pipes. This project demonstrates complete simulation workflow from geometry creation through results interpretation, providing valuable insights into advanced heat exchanger performance.

Project Overview

This simulation investigates a triple concentric tube heat exchanger (TCTHE), an enhanced design that improves upon traditional double-pipe configurations by adding an intermediate tube. The model features three distinct flow channels with different temperature fluids, creating multiple heat transfer interfaces within a compact arrangement.

Key Simulation Parameters

• Geometry: Three-dimensional concentric tubes modeled in ANSYS DesignModeler
• Mesh: 1.96 million elements generated using ANSYS Meshing
• Flow Conditions: Laminar flow regime for all domains
• Thermal Conditions: Temperature differentials between all three fluid streams

Methodology and Approach

Geometric Configuration

The heat exchanger consists of three concentrically arranged tubes creating separate flow paths:

• Inner tube: Water at 280K with 0.1 kg/s mass flow rate
• Middle annulus: Water at 330K with 0.05 kg/s mass flow rate
• Outer annulus: Water at 290K with 0.05 m/s inlet velocity

Simulation Setup

• Laminar flow model implementation
• Energy equation activation for thermal analysis
• Appropriate boundary conditions at inlets, outlets, and walls
• Interface definitions for thermal interactions between domains

Solution Strategy

• Sequential solving of flow and energy equations
• Convergence monitoring for momentum and thermal residuals
• Post-processing of temperature fields and heat transfer metrics

Results and Analysis

Temperature Distribution

The simulation reveals comprehensive temperature patterns showing:

• Gradual cooling of the middle hot stream along the exchanger length
• Simultaneous heating of both inner and outer fluid streams
• Complex thermal gradients at the interfaces between domains

Heat Transfer Performance

• Quantification of heat exchange between each pair of fluid streams
• Analysis of local and overall heat transfer coefficients
• Effectiveness evaluation compared to conventional designs

Engineering Insights

• Demonstration of the TCTHE’s ability to facilitate simultaneous heat exchange between multiple fluid streams
• Identification of thermal performance characteristics specific to triple concentric arrangements
• Practical considerations for design optimization and operational parameters

Learning Outcomes

This project provides practical experience in:

• Modeling complex multi-domain heat exchanger geometries
• Configuring multi-stream heat transfer simulations
• Analyzing thermal interactions between multiple fluid domains
• Evaluating performance metrics for advanced heat exchanger designs

The simulation techniques demonstrated are applicable to various thermal management challenges across process industries, HVAC systems, and energy recovery applications.