SU1663337A1 - Electric air heater - Google Patents

Abstract

The invention relates to heat engineering, in particular, to designs of electric air heaters for heating air, maintaining temperature conditions in industrial and domestic premises, and conducting various technological processes. The purpose of the invention is to increase the heat output by providing a uniform flow around the gas stream and increasing compactness. When the unit is working, the impeller 6 of the fan, rotating from the actuator 11, sucks cold air through the inlet 2. The radial channels in the gas-permeable shell (GO) 5 introduced into the fan impeller 6 pass through. The air is heated by the heat generated by a corrugated conductive insert forming together with the layers of electrically insulating material the said radial channels. The heating of the conductive insert GO 5 is performed by applying voltage from the power supply 8. To ensure a uniform flow around the conductive insert over the entire length of GO 5 and reduce the likelihood of its local overheating, the radial channels are made with an orifice section increasing from the inlet 2 along the GO 5 axis or making an insert of the parts with different sizes of corrugations. 1 D.P.-ly, 3 Il.

Description

The invention relates to heat engineering, in particular to the design of electric air heaters for heating air, maintaining the temperature in industrial and domestic premises and carrying out various technological processes,

The purpose of the invention is to increase the heat productivity by ensuring a uniform flow around the gas stream and increasing compactness,

FIG. 1 shows the electric air heater installation, general view; in fig. 2 - a general view of the shell, the conductive insert of which is made of several parts; .on FIG. 3 shows section A-A in FIG. 2

The electric air heater unit comprises a cylindrical case 1 with inlet and outlet openings 2 and 3, the last of which is located in its side wall 4, a centrifugal fan installed inside it and a gas-permeable shell 5 placed coaxially with the impeller b of the fan and including an electrically conductive insert 7, connected to power supply 8. At the same time, the gas-permeable shell 5 is inserted into the impeller 6 of the fan with the location of one of its ends in the zone of the inlet 2 of the housing 1 and is formed from alternating layers 9 of an additionally installed electrically insulating material and the above-mentioned electrically conductive insert 7 made transversely corrugated to form between corrugations the inserts 7 and the layers 9 of the electrically insulating material of the channels 10 radially directed to the side wall 4 of the housing 1. The passage section of the channels 10 is made increasing from the entrance rsti 2 along the axis of the shell 5,

The conductive insert may be made of at least two parts (three parts are shown in Fig. 2) having different height and pitch of the corrugations, increasing along the axis of the shell 5 from the inlet 2.

The impeller 6 of the fan is placed on the drive shaft 11.

Electroheater installation works as follows

From the power supply 8, a voltage is applied to the electrically conductive insert 7 of the gas-permeable shell 5, where

heat energy The impeller 6 of the fan, rotating from the drive 11, sucks cold air through the inlet 2, the passage of the radial channels 10 formed by a corrugated electrically conductive

by the insert 7 and the layers 9 of the electrically insulating material, the air is heated and discharged through the outlet 3 to the consumer,

The implementation of the channels 10 with the passage section increasing from the inlet 2 along the axis of the gas-permeable shell 5, which can be implemented, using corrugated metal as the conductive insert 7

tape with increasing along the axis of the shell 5, the height and / or pitch of the corrugations, ensures a uniform flow around the conductive insert 7 along the entire length of the shell 5. This avoids a local decrease

the air flow rate of the material of the electrically conductive insert 7, which reduces the probability of its local overheating. In addition, the insertion of the shell 5 into the impeller 6 of the fan and the constructive implementation of the electric heating element in the form of alternating turns of the electrically conductive insert 7 and layers 9 of the electrically insulating material allows, due to the developed heat-exchange surface

to increase the heat output and compactness of the electric air heater unit. In the manufacture of gas-permeable shell 5 it is advisable specified change in the size of the corrugations (their pitch and height)

conductive insert 7 to produce

Claims (2)

discretely, using for this purpose at least two corrugated conductive tapes differing in the size of corrugations. Claim 1. Electroheater installation, comprising a cylindrical housing with inlet and outlet openings, the last of which is placed in its side wall, a centrifugal fan installed inside it and a gas-permeable shell placed coaxially to the impeller of the fan and including an electrically conductive insert connected to the source power supply, characterized in that, in order to increase the heat output by providing a uniform flow around the gas stream and to increase the compactness, ronitsaema shroud wound up — into the impeller of the weshne ure with the location of one of its ends in the zone of the inlet of the housing and is formed from alternating layers of an additionally installed electrically insulating material and an electrically conductive insert embedded transversely corrugated to form channels between the corrugations and layers of the electrically insulating material, radially directed toward the side wall of the housing, the flow area of the channels being made increasing from the entrance opening along the axis of the shell. 2. Installation according to claim 1, of which is an electrically conductive insert made of at least two parts having different height and pitch of the corrugation. Aa Fig.Z