Air-conditioning

Basics:

In which range does the so-called comfort zone lie?
The cozy range, defines the comfort zone in a h, x-chart. The temperature should be between 20-24°C and the relative humidity should be between 35-65%. Dependent on the starting point, it may be necessary, to heat, cool, dehumidify or to humidify.

Lars Keller –Compression chiller guide
Image: Cozy range in the h, x chart (Lars Keller –Compression chiller guide)

Which possibilities for air distribution exist?
In general we distinguish between air transport and air distribution.

For air transport, airtight tubes are used. In dependence of the necessary air volume and the tube length, acr chiller rent uses airtight tubes to transport air with the following diameters::

Tube diameter D Ø [mm]
425
500
600
800
1000
Table: Airtight tubes
According to the following air resistance chart, the required air tube diameter can be determined dependent upon the air volume current (m3/min). Herewith is to be noted that the pressure loss is to the 2nd power to the volume current, i.e. a double volume current causes a fourfold pressure loss.
Image: Air resistance chart
The air volume current of the mobile ventilation system can be divided according to requirement and request at the ventilation device.
Air volume current of mobile ventilation system
Image: Air volume current of mobile ventilation system
For air distribution, porous textile air tubes are used. These are connected directly to the airtight tubes and distribute the relatively high air volume current uniformly over the room. Besides the draft-free air distribution, further advantages lie in the simple and fast placing as well as the optically impressive design.

Typical air distribution variants by means of textile air tubes:

Air distribution variants of textile air tubes
Image: Air distribution variants of textile air tubes

Cooling capacity calculation:

How is the cooling requirement of a room, hall or tent determined?

In dependence of the room height, the geographic alignment, the insulation, the window areas as well as the number of people and other loads such as computers, the necessary cooling capacity needs to be observed individually. As a criterion, following experience values can be assumed

  • Offices 40 – 60 W/m3
  • Hall 60 – 80 W/m3
  • Tents 80 – 100 W/m3
For the cooling capacity calculation in halls or tents a maximum room height of 4m are taken into account. Per person, a load of about 120 to 150 watts can be assumed
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