Rate, simulate, and design shell-and-tube heat exchangers

Xist^® is an incremental program that contains HTRI’s latest pointwise methods based on extensive shellside and tubeside condensation, boiling, and single-phase data. The heat transfer and pressure drop correlations are continually improved as a result of our ongoing research.

As a module in Xchanger Suite^®, Xist lets you quickly transfer applicable case data to other components like Xvib^® or Xace^®.

Features

• 3D incrementation calculates localized profiles for heat transfer and pressure drop.
• Integrated tube layout tool allows complete customization of layout and is based on a full ASME mechanical design.
• Input via hierarchical data panels or TEMA specification sheet.
• Vibration screening warns of probable vibration problems.
• Extensive visualization tools show exactly how the exchanger is performing.
• Integrated physical property system eliminates requirement for additional property generation software. Xchanger Suite includes VMGThermo™, an extensive and rigorous fluid physical property generator from Virtual Materials Group, Inc.
• Includes built-in interface to most process simulators and mechanical design software.
• Can be embedded as a unit operation in any process simulator supporting CAPE-OPEN.
• Both input and output can be displayed in multiple unit sets, including user-defined sets. Dynamic display of values in all unit sets.
• Loads input files from HTFS™, Honeywell UniSim^® Shell-Tube Exchanger Modeler, and Aspen Shell & Tube Exchanger™.
• Integration with Exchanger Optimizer™ provides embedded costing features, which include fabrication, installation, and operational estimates for design cases.

Geometry Specifications

• All TEMA front head, rear head, and shell styles
• Plain, low-finned, continuous-finned, and longitudinal-finned tubes
• Twisted tape inserts and internal microfin tubes
• Up to 24 tubepasses
• Single-segmental, No-Tube-In-Window (NTIW), double-segmental, rod-type baffles, helical baffles, EMbaffles^®, SquareOne™ baffles, and non-baffled configurations
• Single shell, shells in series, shells in parallel, and series/parallel combinations
• Detailed reboiler piping specification

Calculation Features

• Rigorous heat transfer and pressure drop calculations using a 3D incrementation scheme that divides the exchanger into a large number of zones
• Flexible process input allowing specification of known process information (temperature, weight fraction vapor, and/or flow rate) with the program calculating missing information based on energy balance
• Three modes: rating (known duty and geometry), simulation (unknown duty and known geometry), and design (known duty and unknown geometry)
• Automatic screening for flow-induced acoustic and mechanical tube vibration
• Specialized calculations and procedures for kettle reboilers, flooded evaporators, thermosiphons, reflux condensers, and falling film evaporators
• Optional specification of heat transfer coefficients and safety factors

Design Tools

• Automatic optimization of shell diameter, baffle spacing, number of tubepasses, and tube length
• Grid design option to vary geometry over user-specified ranges and step sizes
• Design constraints to prevent selection of undesirable designs
• Best buildable design determined using Smart Design approach, which employs heuristics to find optimal shell size, tubepass arrangement, baffle spacing, and tube length
• Embedded Ultra engine to generate rapid deign results
• Smart Design used in combination with a grid approach to access a wider range of parameters such as shell or baffle type

Outputs

• Extensive set of spreadsheet-style output reports can be printed or exported to Microsoft^® Excel^®
• Summary reports with overall results in one or two pages
• Detailed reports for local profiles of all important parameters (temperature, pressure, heat transfer coefficients, heat flux, etc.)
• Standard TEMA specification sheet
• 2D and 3D scaled drawings provide visual confirmation of exchanger geometry, allowing for quick identification of performance issues
• User-defined graphs for easy accessibility