Aspen PIPE™
Calculating pressure losses and mass flowrates in unbranched process pipelines with single-phase and two-phase flows
PIPE™ is a versatile tool aiding the design and performance checking of unbranched pipeline systems carrying single-phase or two-phase (single or multicomponent) fluids. It allows the user to optimize pipeline size for available pumping power/pressure drop. PIPE can handle large pressure changes where fluid properties vary, including choking flow with single and multiple chokes.
Features
Technical summary
- Incorporate environmental heating and cooling by specifying an overall heat transfer coefficient and the outside temperature or heat flux
- Calculate pipe diameter for specified flowrate and allowable pressure drop
- Determine overall pressure drop for given mass flowrate and pipeline geometry
- Calculates pressure drop across each fitting and along the length of the pipe resulting in the sum pressure drop
- For two phase flow, at each calculation step the flow regime (e.g. bubbly, slug or annular) is estimated from widely accepted HTFS® methods
- Compute flowrate for specified pressure drop and pipe diameter, including
critical mass flowrate for high velocity flow
- Methods for estimating critical flow parameters are sophisticated and allow for non-equilibrium effects
- Multiple choke calculation applicable to safety valves and relief systems determining the number of choke locations which will occur and the resulting mass flow
- Pipe Fittings – Any fitting performance may be modeled by a velocity
head coefficient. A fixed pressure drop (or rise) can be specified. The following
standard fittings can be modeled by PIPE with built-in specific two-phase
correlations:
- Straight lengths
- Circular or mitre bends
- Contractions and inlets
- Enlargements and outlets
- Globe and gate valves
- Ball and butterfly valves
- Thin orifice plates and nozzles
- Thick orifice plate
- A pipeline build interface simplifies the entry of pipeline information. The order and number of fittings in the pipeline can be easily selected, assembled and changed as required
- Graphical Output – Display the variation of pressure with length
along the pipeline as well as a two-phase flow pattern map. Process conditions
at any point along the pipeline may also be viewed. The following are available:
- Velocity
- Temperature
- Pressure
- Quality (vapor mass fraction)
- Vapor and liquid density or velocity
- Summary output showing an isometric sketch of the pipeline
- Tabular Output – The following are available:
- Process data
- Pressure drops
- Velocities
- Liquid/vapor properties
Benefits
- Improved design - PIPE allows for rapid sizing of single-phase and two-phase process pipework taking full account of thermodynamic effects. It brings standardization of these design procedures replacing ad-hoc methods.
- Increased engineering efficiency - The two-phase flow mapping of PIPE offers engineers in process operating companies and engineering contractors a means to quantify flow pattern and local conditions throughout a process pipeline taking account of overall configuration. This allows the engineer to verify the stability of flows regardless of pipe system topography.