SINETZ Program features

The graphical user interface SINETZ is the pre- and postprocessor of SINETZ. All inputs can be made using SINETZ.

A wide range of control functions enables the user to check the input data easily. All results can be displayed and checked, reports are generated.

For a detailed presentation please refer to the SINETZ feature list and the SINETZ tutorial.


System input

The system has to be divided into pipe sections. A pipe section consists of a pipe segment with a constant diameter without branches. The calculation parameters are entered by means of a graphical interface. The system geometry is drawn by the mouse, additional values like segments lengths, node height, components and boundary conditions are added by dialog windows and mouse input.

The program user is supported by integrated expan­dable databases.

Detailed system inputs

General features

  • SINETZ calculates models with up to 15.000 pipes and up to 15.000 nodes.
  • Plausibility of input data is checked and detailed error messages are provided
  • An online help is available


  • Selectable unit for flow input/output of various mass flows may be m³/h, kg/s or t/h.
  • Selectable unit for pressure can be bar, mbar and Pa (pre-defined).
  • Any units can be defined by the user


  • Graphical input of the entire pipe network by mouse. Additional parameters like segments lengths, node heights, components and boundary conditions inserted in dialog windows or selected by mouse.
  • DXF import, CSV import
  • Any cross sections of pipes may be analyzed. At circular or rectangular cross the outer diameter and wall thickness are entered (or height and width, inside). Other cross sections require the input of the hydraulic diameter and the equivalent circular diameter.
  • Alternative editing of data in lists.
  • Automatic creation of node and segment names (may be changed by the user).
  • Pipe names can be assigned to segments.
  • Pipe names may be used for assigning data and checking input parameters.
  • Regions can be defined and named, e.g. „existing system“, „news system“. Segments may be assigned to several regions.

Zeta values

  • The zeta value at reducers/expansions, orifices, branches, tees, y-pipes and bends can be determined by the program and must not be entered by the user. The zeta value is calculated basing on the geometry and the flow state.
  • Resistance values at instruments/ components may be inserted as zeta- or kv -values.
    The Zeta-values/ kV -values are represented by symbols.
  • Different symbols for the representation of instrument are available.
  • Zeta values of instruments may be taken from a user expandable database.
  • If the norm zeta values in the database depend on nominal diameter, the norm zeta value of an instrument is adjusted automatically after changes in dimension.
  • Non-return valves with given flow direction may be inserted. Depending on the flow direction the program opens or closes the gate.
  • Zeta values can be defined independent of velocity, volume flow or mass flow.
  • Regulation valves can be defined by the given mass flow

Pumps/ fans

  • Pumps /fans are defined by their curves and shown by symbols.
    The pump curves can be taken from the user expandable database.
  • Pumps /fans can be activated d depending on load cases.
  • Pump speed and impeller diameter can be inserted depending on load cases. The pump curve is adapted to the load case by iteration.
  • The NPSH value at pumps is checked automatically if the required parameters have been defined at the pump input.


  • Vessels with individually defined connection points can be placed into the model. Each connection point can be completed by an additional zeta value.
  • The internal connection between connection points can be made individually. This can be used for example to simulate two independent circuits inside a heat exchanger.


  • Input of the insulation of free-laid pipes and buried pipes with circular cross section.
  • A temperature depending coefficient of thermal conduction can be entered for the insulation
  • The coefficients of thermal conductivity can be defined for pipes, insulations, insulation jackets and for the soil at buried pipes.

Various inputs

  • SINETZ enables to insert sprinklers into a piping system.

Graphical representation
  • Various text and graphic files (*.jpg, *.bmp,  metafile, dxf  or hpgl) can be inserted for documentation purposes
  • Insertion of a background image
  • By means of a symbol editor program additional symbols can be created and stored in a database. Zeta values can be added to these symbols, too.
  • Using the symbol editor  more vessels with individually designed connection points can be created and stored in a database

Load cases

Simulation of different operation states in the system.
Each operation state requires the definition of one load case. One medium per load case is defined.

Operation states, boundary conditions
  • Pressure, temperature, medium, inputs and outputs can be entered load case dependent to simulate various operation states. under the condition that the system is not over- or under determined
  • Pumps and fans can be switched on/off depending on load cases
  • Load case dependent input and output of energy flows at nodes.
  • Resistance coefficients or pressure drop at components/instruments may be entered load case dependent. This is used to cut off parts of the system for the simulation of various operating states.
  • Load case dependent input of environment conditions like wind velocity, ambient temperature or soil temperature.

SINETZ media and databases

Different from SINETZ, in SINETZfluid only water and fluids are available media.

Media and databases


The following list of media is available:

  • Water    steam table acc. to IAPWS 1997  is implemented
  • Steam
  • Constant fluids
  • Temperature depending  fluids
  • Pressure  depending  fluids
  • Any gas
  • Gas mixture
  • Flue gas
  • Air
  • Helium
  • Methane
  • Nitrogene


The following data can be taken from SINETZ databases:

  • Pipe dimensions
  • Reducer dimensions
  • Pipe texture
  • Insulation data
  • Zeta- /kV -values of instruments
  • Pump curves, fan curves
  • Gas values (gases and gas mixtures)
  • Media

Databases may be edited by means of dialog windows or by an ASCII-Editor.
A mass import function by csv files is available for pump data.


The calculation output is shown graphically and in tables. The result parameters to be shown in the graphic can be selected manually. Detailed results are shown by a double-click on the node or segment.

Analysis details
  • Intermeshed networks of any complexity are analyzed.
  • Any cross sections are calculated.
  • The numbering of networks and advance estimation of quantity injection is carried out by the program.
  • The discretization of segments for the analysis of compressible media is done by the program.
  • Pumps and fans are calculated using their characteristic curves.
  • Addition of several zeta-values per segment.
  • Zeta-values at right angled and sloping branches and runs are calculated by the program. Fillets are considered.
  • component Y-PIPE: the zeta values are determined by the program
  • Resistance coefficients of bends, reducers and expansions are determined.
  • Calculation of zeta values of orifices depending on pipe diameter and diameter of the throttle diameter
  • Zeta values of regulating valves are determined iteratively for a given mass flow.
  • Zeta values of non-return valves are iteratively determined by the given flow direction
  • Calculation of the compressibility factor depending on pressure and temperature in gas mixtures (not for SINETZfluid).
  • Heat loss across pipe insulation is considered for buried and free laid pipes acc. to DIN EN ISO 12241 (not for SINETZfluid).
  • Heating-up of the medium through insulation (if outside temperature > medium temperature) is considered (not for SINETZfluid).
  • The mass flow of fluids is determined iteratively at heat exchangers due to energy flow and output temperature (optional available program SINETZFW, district heat piping)
  • Calculation of condensate quantity at heating up (by approximation) and in stationary operation case (not for SINETZfluid)
  • Orifice dimensioning acc. to EN ISO 5167-2:2003

Results and reports

For documentation purposes the output files can be exported in rtf and pdf format including user defined headers and footers.
Alternatively the results can be shown tabular. Exceeded values are highlighted there.
Pressure and temperature curves are shown graphically.

SINETZ report generation
In input mode as well as in results mode a SINETZ report can be generated including all inputs and outputs. Basing on  a standard format file the input and output tables are created directly by the input tables and results of the current project.

The SINETZ templates can be adapted to the user´s needs. After revising the calculation the report is updated automatically.

Representation and documentation of results
  • Output of the results in English or German.
  • All results are shown graphically and in tables. An output file in ASCII format is created.
  • The input of an alternative company logo or text field makes it easier to work on commission orders.


  • The graphical representation of the results at nodes and segments may be controlled by the user.
  • Parameters of nodes and segments to be shown in the graphic can be selected by the user.
  • Critical velocities are represented in colors.
  • Critical parameters like flow velocity, mass flow, pressure drop or heat loss can be represented in results tables.
  • Graphical representation of pressure curve
  • Graphical representation of node heights
  • Graphical representation of temperature curve.
  • Output of the graphics on printer or large-format printer (plotter), into the clipboard or into the file formats Metafile, HPGL or DXF.

Documents, tables

  • SINETZ includes an automatic report generation.
    The SINETZ report generation module creates a calculation report including input data and results on the basis of factory templates or user defined samples including input data and results
  • Export of output files in pdf or rtf format with user defined headers and footers
  • The results at nodes and segments may be listed. The list may be filtered, sorted and stored in rtf, html or txt (ASCII) format.
  • New report function creating a standard documentation basing on templates (factory templates) to be used to calculation reports
  • Export of comprehensive calculation results to office programs (e.g. MS Word) basing on standard templates in addition to  the standard output functions
  • A documentation summarizing the results over all load cases for specified nodes and components

Output of the results

Results at pipe segments

  • the sum of zeta values in the segment
  • flow rate and direction
  • velocity
  • friction coefficient Lambda
  • Reynolds' number
  • Changes in pressure
  • Changes in temperature
  • Wall temperature of the insulation  (not for SINETZfluid)

Results at nodes

  • Pressure
  • Temperature
  • total inflow and outflow·
  • density and viscosity of the medium
  • Enthalpy
  • NPSH available

Results optionally can be displayed at every segment of the node (cross sections).

Calculation of pressure and heat loss in district heating networks

SINETZ offers various options for the calculation of district heat piping:

  • At heat exchangers the required mass flow is calculated in case of incompressible media
  • The return system is created automatically basing on the parameters of the flow.
  • The flow and the returning system may be shown separately.
  • The input- and output pressure and temperatures at heat exchangers are checked.

The district heat piping features are part of the SINETZ single user /network license.

Inputs and results

The inputs at heat exchangers are:
- energy flow, output temperature and return node.
To check the pressure at the heat exchanger, the pressure loss of the heat exchanger may be entered.
The program analyzes the required mass flow by means of the heat exchanger parameters and the results at the input node.
The pressure and temperature results are checked. An error message occurs, in case of not allowable pressure or temperatures.
The output file include the results at heat exchangers.