Airway gradient over 100%

[Dinchev]

Hi,
When I change some sloping branches, the percentage gradient looks weird. For example, in Attachment the gradient is 26118%, which in itself is impossible. Is this an error? What is the method for calculating the branch gradient?

Using VentSim Design Premium (Version 5.2.8.6 - 64bit)

[Martin Griffith]

Hi,

The gradient indicates, as a percentage, the vertical component of the airway length compared to the horizontal component.

A gradient of 26118.1% indicates a vertical component of the airway length 261.181 times greater than the horizontal component; that is, a very nearly vertical airway.

A gradient of 10% would indicate an airway increasing 1m in height for every 10m in horizontal length.

If the airway is completely vertical (no horizontal component) then the gradient field will say "Up" or "Down". 

[xiao]

Hi Martin,

are the "up" and "down" showing in the gradient box according to the airflow directions?

my mine model has a opposite airflow direction. By changing the "up" to "down" to a shaft, the shaft just disappeared.

br,

Xiao

 

 

[Martin Griffith]

Hi Xiao, 

Thanks for your message. 

The behaviour when you change from Up to Down is strange, we will investigate that and fix it in a new version. 

However, it is important to remember that airways do not have a direction, unless they have a fixed flow or fan in them. For open airways, the direction of the flow is determined by the Air Simulation. If you do want to reverse the direction of a vertical airway, it is probably better to use the Reverse Tool, rather than use the Gradient property. 

Nevertheless, I will fix the strange behaviour and post here again when the new version is available. 

[Martin Griffith]

Hi Xiao, 

We've just released a new version of Ventsim DESIGN, version 5.4.4.1, which has this strange behaviour on the gradient field fixed. You can find the new version here: https://ventsim.com/download/minor-releases/

Thanks for getting in contact, please let us know if you have any issues. 

[xiao]

On 2/25/2021 at 6:01 AM, Martin Griffith said:

Hi Xiao, 

We've just released a new version of Ventsim DESIGN, version 5.4.4.1, which has this strange behaviour on the gradient field fixed. You can find the new version here: https://ventsim.com/download/minor-releases/

Thanks for getting in contact, please let us know if you have any issues. 

Hi Martin,

thanks for your advice. I will contact our IT to install the new version. 

will let you know if it works.

br,

Xiao