ΣPIPE BLOG
SigmaPipe V3.9 Release
- Details
- Written by Rod Dry
There are two changes associated with this release (apart from the usual collection of small bug-fixes):
1. SigmaPipe now works properly on multi-screen systems. Before, it (and associated widows) would always open on the "primary" (eg laptop screen). However, many people use docking stations and multiple (larger) screens. SigmaPipe will now sense which screen it is on, then re-open next time in the same place. If the laptop is removed from the docking station, then (of course) it will revert to the laptop (only available) screen.
2. A user recently asked if it would be possible to export SigmaPipe numbers (eg pressures, temperatures) to Excel. This has now been implemented - there is a new button on the Result Graph which activates it:
The idea is that the user can select variables of interest in the Result Graph window (on the left), then export these (only) to Excel as a table of data values at each distance step along the line.
SigmaPipe Version 3.8
- Details
- Written by Rod Dry
Version 3.8 is a minor update which takes care of two things:
1. A user recently tried to simulate a system with 3 fume cabinets connected to a common extraction fan plus stack (picture below). SigmaPipe V3.7 (old) did not work properly because it was not configured to recognise a gas-phase network with ambient pressure at multiple inlets and also at the outlet. V3.8 (new) checks for this and fixes the problem.
2. When a pipe splitter is added the user needs to (subsequently) build both downstream lines. There is an issue if one of these lines is built and (in particular) a bend is added before anything at all is added to the other line. When returning to build the (previously ignored) second line, Sigmapipe can then become confused and add pipe sections in the wrong direction. The remedy is simple: just add something (a pipe or a cone) to each of the splitter outlets before proceeding further. A new warning message has been added to remind the user when this happens.
SigmaPipe Version 3.7
- Details
- Written by Rod Dry
Makers of domestic and light industrial air conditioners seem to be leaning more and more towards using refrigerant R-32 (difluoromethane). Being chlorine-free, it is considered on of the least harmful types as far as the ozone layer is concerned. To accomodate this, SigmaPipe has been modified to include R-32 as a new (standard) refrigerant type.
A close examination of enthalpy lookup tables showed that small adjustments were needed for refrigerants, some light hydrocarbons, carbon dioxide and ammonia. These changes only affect enthalpies above the critical point, and only marginally. Nevertheless, please be aware of the change.
A user was kind enough to point out a couple of unhandled exceptions that are irritating because they can cause SigmaPipe to crash. These have now been addressed.
SigmaPipe Version 3.6 Minor Update
- Details
- Written by Rod Dry
There were some issues with data for (recently added) ethanol that needed fixing. These have been addressed in the most recent version (note there is no version number change).
SigmaPipe Version 3.6 Is Now Available
- Details
- Written by Rod Dry
This update is essentially a response to user queries involving fluid types not (yet) present in SigmaPipe. One involved the use of oxygen-helium mixtures in a medical context, and the other was related to safety and potential leak conditions around ethanol storage tanks. New fluids in this version are helium, ethanol and methanol (bringing total fluid types to 35).
A number of small bugs were exposed in version 3.5. These have been identified and removed.
SigmaPipe 3.3 Minor Update
- Details
- Written by Rod Dry
A minor update for SigmaPipe 3.3 has just been loaded (with no version number change).
This update is a response to a user request to make it easier to edit orifice plates (and venturi meters). Before, with a right-click edit only orifice diameter (or venturi throat diameter) could be changed. The new version allows more flexibility in this regard.
For an orifice the user can now edit orifice ID, orifice plate thickness and pipe stub length.
For a venturi the user can now edit throat ID, converging section length, throat length and diverging section length.
SigmaPipe Version 3.5 Has Been Released
- Details
- Written by Rod Dry
This release has two changes:
1. A user in Europe has been investigating addition of nano-particles to water in order to increase heat transfer rates. This is an intersting area of research - it seems heat transfer can be increased significantly this way. How to describe such a system in SigmaPipe is, of course, a completely new challenge. SigmaPipe V3.5 allows users to select a "base" fluid (water in this case), then modify individual properties (eg density and thermal conductivity). The resulting (user-modified) fluid can be selected and used in the normal way. Training Module 14 (new) explains this in greater detail.
2. A user from New Zealand recently requested assistance with setting up a gravity-flow distribution system (for cattle watering). A new gravity flow quick-start option set has been added to make this easier in future:
SigmaPipe V3.3 is Now Available
- Details
- Written by Rod Dry
SigmaPipe Version 3.3 has just been released. It features two significant changes:
1. The fluid component list has been expanded to include hydrocarbons up to C10. This also involves a modified (and expanded) fluid source interface to manage the revised component list.
2. An ability to simulate countercurrent and co-current heat exchangers has been added. A new training module (No 13: Heat Exchanger Types) shows how to use it.
SigmaPipe V3.4 Minor Update
- Details
- Written by Rod Dry
A minor update has just been uploaded in response to a user request. This user was having some difficulty working out how to connect a pipe to a mixer - the standard method using Line Builder (in light green background mode) was not well explained and needed some improvement. To help with this, the new version has an additional (direct) right-click option for "Connect Open Line" (see below).
Two new slides (47 & 48) have been added to the Reference Manual (PowerPoint Module 2) to explain this more fully.
SigmaPipe V3.2 is Now Available
- Details
- Written by Rod Dry
SigmaPipe 3.2 features a new fire water distribution capability. A new quick start option has been added for this (Training Module #12 explains how to use it).
Several minor bug fixes and improvements have also been implemented.
SigmaPipe V3.4 Has Been Released
- Details
- Written by Rod Dry
The latest release includes a further four hydrocarbon fluids which round out fluid type options for light hydrocarbons (up to C12).
Orifice plate flexibility has been further enhanced to allow upstream and downstream bevels - this allows (for example) critical flow orifices with thick plates and a significant inlet bevel (as shown below).
SigmaPipe V3.1 Has Been Released
- Details
- Written by Rod Dry
Version 3.1 has just been released. This upgrade has the following changes:
1. For multicomponent systems two equation-of-state options (Peng-Robinson and Soave-Redlich-Kwong) have been added. Training Module 10 has been modified to incorporate this.
2. Chlorine (Cl2) has been added in response to a specific user request.
3. Refrigeration cycle options have been added (together with four refrigerant fluid types: R11, R12, R22 and R134a). A new training module (Module 11) has been added to deal with the specifics of simple refrigeration loops.
4. As usual, various bug fixes have been applied. In particular, there is a change in the calculation procedure for heat exchanger tube bundles with phase change inside the tubes - there was a bug in V3.0 which gave incorrect results (this has been corrected in V3.1).
New Air Conditioner (Refrigeration Loop) Option