Xphe
Xphe designs, rates, and simulates plate-and-frame heat exchangers. A fully incremental program, Xphe calculates each plate channel individually using local physical properties and process conditions. A unique, research-based port maldistribution procedure is used to determine the flow down each plate channel.
Process Specifications
Xphe handles the following process conditions:
- single-phase
- laminar and turbulent flow
- condensation
- pure fluids and multicomponent mixtures
- superheated, saturated, or partially condensed at the inlet
- subcooled, or partially or totally condensed at outlets
- boiling
- pure fluids and multicomponent mixtures
- subcooled, saturated, or partially vaporized at inlets
- superheated, or partially or totally vaporized at outlets
Geometry Specifications
Xphe handles characteristics common to most commercially available plate-and-frame heat exchangers:
- plates with chevron angles from 0° to 90°
- common plates
If the plate is not available in the data bank, all details of the plate geometry can be specified. - up to six passes
Any number of plates per pass are allowed. - cocurrent or countercurrent flow
- up to five different plates
The plates can be combined to yield 15 separate effective channel types in the exchanger.
Calculation Modes
Xphe operates in design, rating, and simulation modes.
Rating
In the rating mode, the program calculates expected heat transfer coefficients and pressure drops for a specified geometry. These are compared to required heat duty, and the difference is reported as under- or overdesign.
Simulation
Using an iterative procedure in the simulation mode, the program adjusts for omitted process conditions until the predicted heat duty matches assumed process conditions. For example, if the flow rates and inlet conditions are specified for both streams, the program determines exit process conditions.
Design
Xphe contains two distinct design options: classic design and grid design.
In the classic design mode, Xphe uses a unique combination of analytical and computational solutions. The analytical solution sets the basic exchanger design, including the initial number of passes and the number and combination of plates required to meet heat transfer and pressure drop limits. The computational solution fine-tunes the design for final selection. The final result of the design process is a single exchanger that satisfies all your specified criteria. In the grid design mode, you have complete control over which geometry is varied and over what range each geometric parameter is varied. The program runs all possible permutations and automatically selects the best available design.
Calculation Methods
HTRI validated the single-phase calculation methods used in Xphe with research data taken on plate-and-frame heat exchangers from three different manufacturers. Phase-change methods are based on HTRI research data taken on one plate style as well as all information available in the open literature. HTRI continues to compile additional research data at our research facility; as improved correlations are developed, the methods are incorporated into Xphe.
Users can specify f- and j-factor curves or data according to experiments, HTRI research, or plate manufacturer information.
Special Features
- Database file available from manufacturers that includes standard plates and can be tailored to meet specific requirements and updated as new plates are introduced, with exact heat exchanger plate geometry specifications
- Full support in the GUI for a user-defined plate database, to which a new plate can be added with a single click
- Scaled 2D drawing of plate pack
- Non-Newtonizn fluids handled through the input of Power Law constants