GB2165433A - Modular kennels - Google Patents

Abstract

A kennel unit is formed of glass reinforced plastics members and is provided with ventilation slots (1-4). A vertically sliding door is provided at the rear of the unit and a mesh door is provided at the front. Kennel units may be located on one or both sides of a service corridor. <IMAGE>

Description

SPECIFICATION Modular animal housing ventilation CONTENTS 1. Introduction 2. Ventilation Requirements 3. Natural Ventilation Mechanisms 4. Conclusions 1. Introduction An earlier report by Buro Happold in April 1979 touched upon the ventilation of these kennel units and discussed the use of materials for the Control of Condensation in the kennel units. It is not intended that ventilation be controlled but slots have been designed into the GRP panels which will allow some natural ventilation for the removal of odours and the provision of fresh air.

This brief report is an assessment of the effect that these slots will have on the air change rate within the slots.

2. Ventilation Requirements There is little information available relating to the physical requirements of kennelled dogs. Human comfort levels are not valid as design criteria as dogs are capable of adapting to a much wider range of conditions and are not as sensitive to the presence of odours as humans. Ventilation is chiefly required to prevent condensation by ensuring that internal and external vapour pressures are never greatly different and to keep odours to reasonable levels.

3. Natural Ventilation Mechanisms The locations of the slots and their sizes are shown in Figure 1. The slots 1,2,3 and 4 are left when the roof unit is fitted to the wall units. The low level slot (No. 5) is formed beneath the door as a urine drain but it will also allow air in at a low level.

There are two methods by which air movement is naturally induced in a space: (a) wind, and (b) the buoyancy forces caused by a temperature difference between the inside and outside.

It has been shown ' that there are circumstances for each to predominate and in general the resultant airflow will relate to either one or the other as shown in Figure 2.

(' See BRE Digest 210 - "Principles of Natural Ventilation")

Fig. 2 Cross Ventilation of Simple Buildings (Source: BRE Digest 210) Because the kennels are fairly low in profile and may have a corridor cover fixed overthe higher side it is unlikely that significant differential wind pressures will develop and temperature therefore is likely to be the main cause of air movement except where indoor and outdoor temperatures are similar; this has been assumed for the analysis.

Dimensional analysis of the flow of air around cracks and the buoyancy effects of air leads to the relationship as shown in Figure 2 namely: 2A9 g H QB = CO AB ( ) 9 where A5 is given by the inverse square relationship 1 1 1 ~ = - + A8 (A1 + A2 + A5)2 (A3 + A4)2 As the discharge coefficient which is generally given a value equal to that for a sharp edged opening, whcih at high Reynolds numbers 0.61. The length/width ratio of the openings involved means that this value is likely to be conservative.

Because of the difficulty of predicting temperatures for the wide range of climatic conditions that may be experienced, a set of general solutions has been derived for the openings based upon the mean temperature (0 = (91 + 02)/2) and the temperature difference (A0 = 91 - 02) which allow the effects of different conditions to be assessed.

Figure 3 shows the graphical relationship between 9 and A9 which shows that for the majority of forseeable conditions that air change rate is high.

This is to be expected because, by comparison with a normal size room where a natural air change rate of r1 per hour might be expected from a partiaiiy open window, the volume of the kennel is small and the ventilation slots large.

4. Conclusions The resultant ventilation rates are ciearly adequate for the climatic conditions shown particularly because reasonable diurnal temperature variations are experienced in temperate zones which will allow the kennels to heat and cool and encourage a difference between inside and outside. Reference to Figure 3 shows, however, that where temperatures are higher the air change rate will reduce for a given temperature difference and, ifthere is little variation in daily temperature, it could come down to almost zero. In these cases it would be wise to increase ventilation possibly by making the dogs' door out of a mesh rather than solid GRP. Experience with the kennels will indicate where special provisions are needed.

The addition of these ventilation slots will inevitably result in a slight reduction in the resultant temperature within the kennels. We believe, however, and experience in the last winter has shown, that their inclusion does not cause a problem with low temperatures and the improvement in ventilation that accrues is well worth the slightly lower temperature experienced in the winter.

Claims (7)

CLAIMS The main features are: 1. Natural ventilation secured by scientific design. 2. Low condensation factor 3. The application of GRP material in construction panels makes the following possible: (a) a weatherproof building (b) internal moulding of corners and other design features to facilitate cleaning and to ensure a high standard of hygiene and low propensity to offensive odours. (c) minimises damage by animal tooth and claw. 4. Roof design enables rainwaterto be carried away without guttering or external piping. 5. Freestanding building which is demountable and transportable. New claims or amendments to claims filed on 24 September 1985. Superseded claims 1-5. New or amended claims: CLAIMS

1. Kennels made of glass reinforced plastics.

2. Walls, roof and floor of the kennels made as above bolted together through weather-proof joints.

3. Ventilation through slots in side of kennel.

4. Kennels have moulded corners and roofs, with opening rooflights and windows in service passage.

5. Intermediate wall panel carrying drainage tube from concave section of roof to rear bottom of that wall.

6. Weatherproof external door with opening window and lower portion which opens separately for animal access.

7. Multiple units have compartment doors of steel mesh in GRP frame.