1. Trang chủ
  2. » Giáo Dục - Đào Tạo

THIẾT kế THÔNG GIÓ NHÀ vệ SINH

3 208 1

Đang tải... (xem toàn văn)

THÔNG TIN TÀI LIỆU

Thông tin cơ bản

Định dạng
Số trang 3
Dung lượng 57 KB

Nội dung

Design a ventilation system for the toilets in an Auditoria as shown in the accompanying drawings.. The Male Toilet and Female Toilet should each have separate extract ventilation system

Trang 1

Design a ventilation system for the toilets in an Auditoria as shown in the accompanying drawings

The Male Toilet and Female Toilet should each have separate extract ventilation systems to avoid ‘cross-talk’ and spread of smoke within the ductwork system

The mechanical ventilation rate from Table 3.1 CIBSE Guide B2 (2001) is at least 3 air

changes per hour

For the purposes of this exercise use a value of 8 AC/h

Trang 2

MALE TOILET

The volume of the Male Toilet is: 4.5 x 3.0 x 2.7 m = 36.45 m3

The ventilation rate in m3/h is:

Ventilation Rate (m3/h) = Room volume (m3) x air change rate (ac/h)

Ventilation Rate (m3/h ) = 36.45 m3 x 8 AC/h

= 291.6 m3/h Divide by 3600

The ventilation rate is = 0.081 m3/s

A simple method of duct sizing would be:

Duct area = volume flow rate / air velocity

An appropriate maximum air velocity for a toilet is 4 m/s

(See Ventilation - Ventilation Design section)

Therefore duct area = 0.081 / 4 = 0.02025 m2

If a square duct is used then the duct size is: ( 0.02025 )0.5

= 0.142 m x 0.142 m

The nearest standard size is 0.150 m x 0.150 m

or, 150mm x 150mm

The drawing below shows the ductwork layout for the Toilets

The flexible ductwork may be sized using the same technique as above

Trang 3

Volume flow rate through each flexible = 0.081 m /s / 2 = 0.041 m/s.

A simple method of duct sizing would be: Duct area = volume flow rate / air velocity

An appropriate air velocity for a flexible in this situation is 4 m/s

Therefore duct area = 0.041 / 4 = 0.01025 m2

Cross sectional area = p d2 / 4 d = ( 4 CSA / p )0.5

Therefore flexible diameter = ( 4 x 0.01025 / p )0.5 = 0.114

m = 114 mm diameter

The nearest standard size of PVC flexible is 125mm

The flexible size should be smaller than the duct to which it is attached to enable a boot or branch to be spot welded into position, as shown below

The Female Toilet may be sized using the same method but since the physical dimensions are so close to the Male Toilet then the same duct sizes can be used, this also standardizes the complete ventilation system so that the two fans are also identical

Fans

To choose suitable fans for this example the duct pressure drop and fittings pressure drop would be calculated

If the total pressure drop is assumed to be 200 Pa and the flow rate is 0.081 m3/s (81 litres/s) then a suitable catalogue can be used to pick the fan

See http://www.flaktwoods.com Go to Other Fans section

A tube fan or boxed fan can be used for this project

Ngày đăng: 14/12/2017, 12:26

TỪ KHÓA LIÊN QUAN

TÀI LIỆU CÙNG NGƯỜI DÙNG

TÀI LIỆU LIÊN QUAN

w