The angle factor for radiation to a tube bank is an important quantity in the industrial furnace design. In the past years

the graphical representation was frequently used. In this paper

the formulas calculating the angle factors for radiation to a bank of oval tubes are derived. These formulas are usable for the industrial furnace design. The primary results are as follows. Single bank of oval tubes:The local angle factor at any given point A(Fig. 2) is: Single-Side radiation

Double-Side radiation

where ≤PAE and≤EAG can be calculated from Eq. ( 9 )

(10)

(8) and (5) respectively. Double bank of oval tubes:The local angle factor at any given point (Fig. 3

Fig. 5)is:Single-side radiation (the bank which is far away from the radiation side). Double-Side radiation

FA

D(Kt

K2

K3

B) =FAKi

K2

B) + FA(K

K2

K3

- 6) where /^GAE

/_PmAE and^/PN2AE can be calculated from Eq. (33)

(32)

(28)

(27)

(26)

(25)

(24) and(21) respectively. Some calculated results of the angle factor for radiation to a single bank of oval tubes are given in table 1 as an illustration example.