Colony Population Model

[barratt_sab]

I was looking for a simulation of bee colony population, and it would appear that were was a web-based model (webbeepop) which not longer exists. However, I also found this:

http://www.ars.usda.gov/services/software/download.htm?softwareid=75

which models both bee population and also varroa population.

I can't say that it's easy to run or understand, but I can say that it's not as interesting as looking at a real colony!

 

[drstitson]

i actually started playing with one from scratch a week or so back whilst bored on the plane.

will check out the link.

There is somewhere a nice biological systems modelling language that would probably do the trick - must find that again.

 

[drstitson]

this is quite an interesting model:

http://www.up.ac.za/dspace/bitstream/2263/12797/1/Becher_Brood(2010).pdf

 

[barratt_sab]

i actually started playing with one from scratch a week or so back whilst bored on the plane.

Snap! My initial attempts blew up or collapsed, so I thought I'd try to get hold of something to play with to get a better idea of the dynamics of the system, and this is the only one I've found so far.

There is somewhere a nice biological systems modelling language that would probably do the trick - must find that again.

I'd be really interested to hear about it, if you find it.

this is quite an interesting model:
http://www.up.ac.za/dspace/bitstream...rood(2010).pdf

Thanks for this link - it looks like a very interesting piece. I recently got hold of an old copy of "The Ventilation of Bee-hives" (Wedmore) and was struck by how his relatively simple model of heat production and ventilation in a cluster produced interesting results.

 

[drstitson]

wedmore

"I recently got hold of an old copy of "The Ventilation of Bee-hives" (Wedmore) and was struck by how his relatively simple model of heat production and ventilation in a cluster produced interesting results."

have you seen Dave Cushman's take on the Wedmore work?
(http://www.dave-cushman.net/bee/ventilation.html)

This is what spurred me on to develop my "crown chamber" boxes that are now (finally) fitted to all three hives (with temp/hygro probes attached)

BTW according to my rough calculations a typical range of winter cluster sizes, under a wide range of ambient temperatures (-10 to +10 C) will generate something like 50-125 ml/minute airflow upwards from the cluster!!!!

 

[barratt_sab]

have you seen Dave Cushman's take on the Wedmore work?
(http://www.dave-cushman.net/bee/ventilation.html)

I've obvisouly not made a study of it, but I can understand Dave Cushman's logic.

This is what spurred me on to develop my "crown chamber" boxes that are now (finally) fitted to all three hives (with temp/hygro probes attached)

I cannot find any prior mention of your crown chamber design on the forum (forgive me if I missed it) - I'd be interested to hear more about it. I also remember that you have posted before about having probes in the hives - are they this sort of thing?

http://www.maplin.co.uk/Module.aspx?ModuleNo=220815

 

[drstitson]

barratt_sab

No - i'm using Exo Terra digital temp/hygro devices designed for terrariums.

You can see the sensor and the device in the snaps of the chamber i took whilst installing on a warm UK afternoon last week.

FYI the sealed top box contains 7cm of poly insulation and can be used alone (upturned) if needs be (hence the 9mm framing to give beespace on top edge).
For national hives the chamber can be used in either "hot" or "cold" orientation (not sure yet which is best ..... have both versions made for my dadants as obviously these have obvious rotational symmetry issues and took advantage of one hive having internal insulation for a small colony).

 

[barratt_sab]

Thanks for these photos. I am being dim, I'm afraid - what is the thinking behind the cavity?

It would seem to provide a circulatory route for air rising up from the centre of the brood, but I may (very well!) have misunderstood the intention.

 

[pbh4]

I've obvisouly not made a study of it, but I can understand Dave Cushman's logic.

Dave started out as a nuclear physicist. I would say his description of convection and humidity in the hive is spot on.

Paul (physicist!)

 

[drstitson]

convection

the aim is to a) provide insulated roof/crownboard to prevent condensation above the cluster whilst also b) further assisting the natural convection of moisture away from the cluster.

in addition provides a convenient place to add fondant etc.

 

[barratt_sab]

Dave started out as a nuclear physicist. I would say his description of convection and humidity in the hive is spot on.

Paul (physicist!)

It seems that physicists are attracted to beeking. I used to be a physicist a very very long time ago.

I spent some time working on and with Monte Carlo models for reactor safety analysis (Monk, Keno) and have wondered in the past what would result if you took a similar approach to modelling bee behaviour, apart from the crushing headache, obviously!

 

[barratt_sab]

the aim is to a) provide insulated roof/crownboard to prevent condensation above the cluster whilst also b) further assisting the natural convection of moisture away from the cluster.

in addition provides a convenient place to add fondant etc.

Gotcha - thanks. The bare wood might also act as a useful moisture trap, similar to Dave Cushman's thoughts on the wood fibres in a natural colony.

 

[madasafish]

It seems that physicists are attracted to beeking. I used to be a physicist a very very long time ago.

QUOTE]

Snap...

 

[For want of a better word]

All very interesting!
How would your beethermodynamics models stand up to a natural shaped comb in say a "natural" Top Bar Hive ?

 

[drstitson]

moisture

"The bare wood might also act as a useful moisture trap, similar to Dave Cushman's thoughts on the wood fibres in a natural colony."

Hopefully not (or at least only a reserve role)!!!! The aim is for the damp air to be effectively channelled down the outer bee space of the hive (ie between "colder" outer wall (relative to roofspace) and the "redundant" outer comb surface (or down beespace at ends of frames depending upon orientation).

I have considered (thanks to a previous poster) adding a pair of angled ply sheets to further channel damp down and out - these will be installed if any sign of persistent damp/condensation within the chamber if conditions allow a quick peek eg when opening for oxalic treatment.

 

[roche]

drstitson, have you got numbers on how your roof design compares with a standard one, in terms of temperature and humidity?

 

[drstitson]

roche

not yet - only just completed and installed!!!!!

However - i don't expect there to be a difference above the cluster as X bees produce X amount of heat and moisture BUT rather a modified distribution of said humidity after rising.

 

[rowbow]

Dave started out as a nuclear physicist. I would say his description of convection and humidity in the hive is spot on.

Paul (physicist!)

I agree.

John (cyclist).

 

[rowbow]

Have you ever thought, the colony could need/use the condensation in the winter months,I have seen bee's collecting water from around the edges of the glass crown boards, so you could be doing more harm than good in removing all of the moister.?
Regards

John

 

[drstitson]

Condensation still likely elsewhere in hive (eg sides), just not immediately above/around cluster.