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3.2.1.2.1.1.2.2, Pressure drop of irrigated packings
In literature there are some graphic methods for determination of the
pressure drop of irrigated packings such as this of Teutsch [27]. Because of the
wide employment of computers for calculations of industrial apparatuses these
methods are no more used and will not be considered.
Good results for many different types of packings are obtained with
equations in the form of that of Zhavoronkov, Aerov and Umnic [33], Eq.(259)-
Chapter 1. To calculate the value of A in this equation under the loading point,
the authors offered the expression:
3 \U48_lll
They showed that by Eq. (259)- Chapter 1 and Eq. (22), it is not
possible to describe all experimental data and to use them for all the cases
existing at their time. So they changed the theoretical equation (259) of Chapter
1, by introducing in it two experimental constants «i and b. The new equation
is:
AP = ^—r. (23)
(a -bA?
t
The values of fl/ and b are as follows:
Ceramic Raschig rings
lo
Less than 30 mm 1 - 1.65xlO" a/e 1
More than 30 mm at A < 0.3 1 1
More than 30 mm at A > 0.3 1.129 1.43
Steel Raschig rings 1 1.39
For theoretical calculation of the value of A by using the experimental
equation of Hikita and Kateoka [69] for the wetted surface area of the packing,
Kolev [70] offered the equation:
