Технические науки/6.Электротехника и
радиоэлектроника.
Ritter D.V.,
Kismereshkin V.P.
The North Kazakhstan state university after M. Kozybaev, Petropavlovsk
The Omsk state technical university, Omsk
High-frequency
heating extended dielectric objects
Drying of wood
heating of bitumen weight, a warming up of a ground and many other things
demand the effective is longitudinal warming up. Many ways among them and hot
air are used, but finally it is electric or thermal energy which heats up the
heat-carrier banished through this or that volume. The most perspective is the
high-frequency heating which essence is reduced to volume warming up in the
field of an object irradiation. Similar furnaces are realised in variety of
designs, with reference to this or that industrial target. Common fault of such
systems is the irradiation of object of drying by the directed high-frequency
stream.
The specified
irradiators (drawing 1) form a ruler with corresponding recycling of not used
high-frequency radiation.
Drawing 1 Ruler of irradiators
It is known, that
the superficial wave guide represents a wire with a covering in a kind
concerning a thin layer insulator or an absorbing layer. And in that and other
case it is electromagnetic system along which raise kvazi THAT a wave (Е00) which prominent feature presence symmetric
concerning an axis of a wire of cross-section components is.
Character of change
of components of a field in a cross-section direction is that, that amplitudes
of fields behind side-altars of the imagined cylinder with radius Х0 (boundary radius) quickly fall down, and in a
longitudinal direction distribution of energy depending on components of a
constant of distribution takes placeg.
The size of
boundary radius where 90 % of energy are concentrated, depends on a covering of
a wire and a parity diameter of a wire – diameter of a covering.
Thus, in section in
side-altars of the area defined in boundary radius, all energy is concentrated
practically, we renounce from the generator. This energy will co-operate with
any not the uniformity placed in given area.
In particular, if
it is a conductor the induced currents will be radiated, and if диэлектрик along with radiation losses and consequently
heating will take place also.
This circumstance allows to carry out
high-frequency heating of the dielectric materials placed in area, limited in
boundary radius.
Thus it is
necessary to solve variety of problems which in go to a circle of
dissertational work.
One of problems is
possible more uniform heating extended
dielectric objects. It can be reached similarly to how it is carried out in the
antenna lattices which elements are raised by a field of an open wave guide. In
our case it is installation of an axis of a wave guide under some corner to axis
of extended object in such a manner that the object beginning is in area with
smaller intensity in comparison with its end.
The following
problem of minimization of reflexion.. It dares in the usual compensatory ways
in the beginning of a line of a superficial wave.
Further it is
necessary to solve a problem of recycling of not used energy (energy in ballast
loadings, the energy reflected from the beginning of a line, the radiated
energy). Unlike existing systems of high-frequency heating in our case of
recycling the considerable part of capacity is subject not, therefore it does
not cause special difficulties.
Schematically
installation for high-frequency heating is presented in drawing 2
Drawing 2
Installation for heating
1-generator
2 - Coordination
device
3,4 - Excitation
device
5,7 - Load
6 - Object
8 - Device of
recycling
Installation works
as follows: energy from the generator through the coordination device arrives
on the excitation device connected to loading which is cooled by water. The
capacity disseminated by object is perceived by the recycling device connected
to the loading also cooled by water.
Literature:
1.
Трошин Г.И., Макарова
Л.И., Худякова В.А., Чистин Э.Ф. Однопроводная линия передачи // Труды НИИКП,
1962.
2.
Семенов Н.А.,
Полыковский А.М. Линии поверхностной волны для передачи телевидения. – М.:
ВЗЭИС, 1963.
3.
Семенов Н.А. Параметры
волны Е00 в линии поверхностной волны // Радиотехника и электроника.
– 1964. – Т.9. – № 9. – С.1634 – 1641.
4.
Ефимов И.Е.
Радиочастотные линии передачи. – М.: Сов. Радио, 1964.
5.
Кисмерешкин В.П., Лобова
Г.Н. Использование открытых линий передачи в технике средств связи //
Информационные технологии и радиосети – 96. Первая международ. научно-практ.
конференция. – Материалы конференции. -
Омск, 1996. – С.29.