PYTHON

PYTHON logo.

WINDOWS-based program that analyses water piping systems for air conditioning applications. PYTHON � Air Conditioning Heating and Cooling Piping Systems Design provides for the analysis of hot and chilled water closed loop systems and also open loop systems such as condenser water piping systems. PYTHON can however also handle any other fluid by entry of the fluid density, viscosity and specific heat. The program handles systems with primary and secondary circuits and is based on the methods and data in the AIRAH/IHRACE Application Manual Air Conditioning Water Piping (DA16). PYTHON includes all the fittings and associated pressure loss data in this manual readily accessible through drop down lists.

Calculations are carried out in a series of spreadsheets. In the first of these the pressure losses throughout the system and the pressure at each node is calculated using the Colebrook White formula. In a second spreadsheet the heat loss or gain from all the pipes in the system are calculated. Coil water flows may be adjusted to account for the heat loss/gain along the pipes to each coil. In chilled water systems a check is made for the possibility of condensation formation. In a third spreadsheet, each coil circuit is analysed and a control valve selection made based on the required valve authority. Two and Three way control valve can be modelled. The out-of-balance pressure loss required to be taken up by balancing valves is also calculated along with the required flow and head for each pump.

The program also determines the total lengths of pipes by material type and size and the number of fittings by type and size in a Cost Estimating Spreaedsheet. Screen Shots

Keywords

pipe sizing, pump sizing, control valve selection

Validation/Testing

N/A

Expertise Required

Knowledge of piping systems is of advantage. A half day training course is recommended.

Users

10 companies in Australia and New Zealand.

Audience

HVAC design engineers, local government and university teaching departments.

Input

PYTHON provides graphical input of the piping layout in schematic form, with separate layers for supply, return, and plant room piping. Primary, secondary and tertiary systems with separate pumps can be modelled. The pipework system components, including boilers, chillers, pumps, head and pressure tanks, coils, condensers, etc., are all entered by selection from a floating toolbox. A comprehensive range of piping materials are provided for and individual pipe sizes can be fixed if required.

Pop-up dialogue boxes allow entry of the various parameters associated with each piping system component (pipe material, coil loads, number of fittings, elevations, etc.) and master defaults, such as coil connections and fittings, are provided to minimise data input. Nodes are automatically inserted and numbered as the piping system is developed. Range and data checking is provided on all input items and a comprehensive check is made on the entered piping layout. Comprehensive help is provided in all dialogue boxes and on each drop down menu describing the various input items.

Output

The results of the detailed calculations are displayed on the individual spreadsheets. A Summary Results Screen displays a summary of the results and provides for printing any of the results. Specific columns from each spreadsheet can be selected for printing. The pressure and temperature at each node is also displayed in another Screen

Computer Platform

Windows 98/NT/2000/ME/XP

Programming Language

Visual Basic

Strengths

The program has many features that make the inputting of data quite simple including automatic copying of the supply network to the return network, user entered default fittings on coils and many other features. A global change facility allows various alternative designs to be quickly and thoroughly investigated.

Weaknesses

Cannot handle cross connected loops and other more complicated configurations. Cannot import CAD files.

Contact

Company:

ACADS-BSG Pty Ltd

Address:

18 High Street
Glen Iris, Victoria 3146
Australia

Telephone:

+61 (3) 9885 6586

Facsimile:

+61 (3) 9885 5974

E-mail:

acadsbsg@ozemail.com.au

Website:

http://www.ozemail.com.au/~acadsbsg

Availability

Contact ACADS-BSG or visit web site for more information. Price: AU$1957 for single machine copy and significant discounts for multi-machine copies. Demonstration copy available for $50.