аэродинамика воздухоочистных устройств с зернистым слоем

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and Sontag as well as methods for porosity identification discussed considering
the cylinder- and ball-shaped granular layers of charging. The chapter presents the
X-ray-gram of ball-shaped granules the diameter of which reaches 9.5 mm and
the dependences of their porosity on a charge form and on the diameters of the
granules and device. Subject to the ratio between the sizes of the dimensions of
the device and granules (D/d), the porosity of granular charging may fall from 30
to 80 %. Granules in the forms of balls, cylinders and irregular Raschig rings were
selected for investigation. Research produced the expressions of the coefficients of
the porosity of granules having these forms. As determined during investigations,
with a ratio between the dimensions of the device and granules (D/d) increasing
the porosity of a granular charge is decreasing. When D/d changes from 5 to 20
the porosity of cylinder-shaped granules decreases from 41 to 38 %. The sharpest
decrease in porosity is obtained when the ratio of the dimension sizes of the device
and granules increases from 1 to 5. The curves of the dependence of porosity on the
ratio of the dimensions of the device and granules (D/d) presented in this chapter
allow determining the medium porosity of a layer composed of granular charging.
Chapter 4 The Peculiarities of Gas Distribution in Devices with a Granular
Charge Layer describes various factors having an influence on gas distribution
within a granular charge layer. Careful attention is devoted to describing device and
granule dimension ratio (D/d) responsible for gas distribution within the layer. The
dependences of airflow rate on device structure and granule sizes are presented. The
chapter examines the ball-shaped granules of different sizes (0.25–8.7 mm) present
in the devices of different dimensions (device diameters reaching 40-94 mm). The
dependences of airflow distribution on the charge layer and airflow rate supplied
to the device are described. As determined during investigations where the initial
airflow rate supplied to the device is from 1–2 m/s, the disparity of gas distribution
in the charge layer does not change, whereas where airflow rate is below 1 m/s
the disparity of gas distribution starts growing (Morales et al. 1951; Price 1968;
Cairns, Prausnitz 1959; Ziolkowska et al. 1983; Dorweiler, Fahien 1959; Bundy
1966; Schwarz, Smith 1953; Leroy, Froment 1977). The impact of the non-isothermal
layer on gas flow distribution is described. The conducted investigations have
revealed that a non-isothermal character of charging has an impact on the distribution
of airflows. It has also been determined that upon increasing the temperature
of gas passed through the granular charge composed of 3 mm granules in diameter
from 293 to 473 K, the initial to maximum rate ratio (W max /W 0 ) decreased by 15%.
This chapter presents and describes the stands intended for research on aerodynamic
processes occurring in charges and analyses their structures. One-cassette and threecassette
devices were analysed in detail (Moscicka et al. 1976; Ziolkowska et al.
1983; Dorweiler, Fahien 1959 et al.). The chapter presents airflow distribution occurring
after gas has flown through the granular layer of charging and a theoretical
calculation of the distribution of gas flow passed through the charge. It describes the