Electric heating is any process that converts electrical energy to heat. Common applications include space heating, cooking, water heating, and industrial processes. The document discusses various electric heating methods like resistance heating, arc heating, induction heating, and dielectric heating. It also covers applications of electric heating in domestic uses like cooking and water heating as well as industrial uses like melting metals and heat treatment processes. The advantages of electric heating are its cleanliness, ease of control, uniform heating, and ability to heat non-conductive materials.

1. MALLA REDDY ENGINEERING COLLEGE
TECHNICAL SEMINAR-2014
ELECTRIC HEATING
Guided by:
G.Stheesh
Assoc.pro
Submitted by:
M.Prabhakar Naik
(10J41A0292)

2. • Abstract
• Modes of heating
• Methods of heating
• Resistance heating
• Arc heating
• Electron bombardment heating
• Induction heating
• Dielectric heating
• Space heating
• Water heating
• Other type of heating’s
• Applications
• Advantages
• Conclusion
• Contents:

3. •Abstract:
Electric heating is any process in which electrical energy is
converted to heat. Common applications include space
heating, cooking, water heating and industrial processes. An electric
heater is an electrical appliance that converts electrical energy into
heat. The heating element inside every electric heater is simply an
electrical resistor, and works on the principle of Joule heating:
an electric current through a resistor converts electrical energy into
heat energy. Most modern electric heating devices
use nichrome wire as the active element. The heating element,
depicted on the right, uses nichrome wire supported by heat
resistant, refractory, electrically insulating ceramic.
Alternatively, a heat pump uses an electric motor to drive
a refrigeration cycle, drawing energy from a source such as the
ground or outside air and directing it into the space to be warmed.
Some systems can be reversed so that the interior space is cooled
and the warm air is discharged outside or into the ground. In this
study various electric heating methods were studied examples and
advantages and disadvantages.

4. • Modes of heating:
a) Conduction
b) Convection
c) Radiation

5. • Methods of heating:

6. • Resistance heating:
a) Direct resistance heating
b) Indirect resistance heating
a)Direct resistance heating: Direct resistance heating offers
manufacturers precise control and directed heat for applications
such as preheating billets for forging, producing unique
hardening patterns on metals, selectively heating forging dies and
maintaining solutions at constant temperature. Direct resistance
heating works only for electrically conductive workpieces.
b) Indirect resistance heating:
Indirect resistance heating furnaces are easy to control, and
operate over a wide temperature range. In addition to heating
metals, they are used for melting glass, sintering ceramics, and
curing coatings. The number of applications continues to grow as
technological developments broaden the operating temperature
range of indirect-resistance furnaces, and the demand for
automatic process control increases.

7. • Arc heating:
a) Direct arc heating
b) Indirect arc heating
a) Direct arc heating: The heating of matter by an electric arc.
The Matter would be solid, liquid or gaseous state. For direct
heating, the heat is transferred from the arc by using single
electrode.
b) Indirect arc heating: The heating of matter by an electric arc.
The matter may be solid, liquid, or gaseous. For indirect heating,
the heat is transferred from the arc by conduction, convection, or
radiation.

8. • Electron bombardment heating:
Electron bombardment may be applied in an experimental loop for
the study of heat transfer phenomena of the liquid metals. The scientists
proved that the electron bombardment heating is a satisfactory technique for
this application, in both forced-convection and natural-convection systems.
• Induction heating: Induction heating is the process
of heating an electrically conducting object (usually a metal)
by electromagnetic induction, where eddy currents (also called Foucault
currents) are generated within the metal and resistance leads to Joule
heating of the metal.

9. • Dielectric heating:
Dielectric heating, also known as electronic
heating, RF heating, high-frequency heating is the process in which a high-
frequency alternating electric field, or radio wave or
microwave electromagnetic radiation heats a dielectric material. At higher
frequencies, this heating is caused by molecular dipole rotation within the
dielectric. At lower frequencies in conductive fluids, other mechanisms
such as ion-drag are more important in generating thermal energy.

10. • Space heating:
Space heating is used to warm the interiors of buildings. Several
methods of electric space heating are used. Here are some of the
space heating types;
a. Radiative heaters
b. Convective heaters
c. Fan heaters
d. Storage heating
e. Domestic electrical underfloor heating
f. Lighting system
g. Heat pumps

11. • Water heating:
Water heating is also a type of heating in which the water is
heated, which is used in industries, domestic usage etc. Here are few
types of water heating;
a) Immerision water
b) Domestic immerision heaters
c) Industrial immerision heaters
• It also has other types of heatings listed below;
a) Electrode heater d) Electric train heating
b) Industrial electric heating e) Induction ladle heater
c) Central heating f) Plasma heating

12. • Present status of heating:
Since electric heating came into use long ago, it has been
developed into products of various forms in many social
places. In particular, recent remarkable progress in
semiconductor switches toward large capacity and high speed
has accelerated its technology improvement and application
expansion. It can be much expected that the development of
analysis technology and control technology using
programmable controllers, will lead to a new electric heating
process. Here are some of the technology of industrial
induction heating, arc heating, induction heating for the food
industry, plasma heating and levitation melting, and surveys
technical and demand trends of electric heating.

13. • Requirements of heating:
• It should have;
a. High specific resistance
b. High melting point
c. Should not oxidize at electrode temperature
d. Should not low temperature coefficient
e. Positive temperature coefficient
f. High ductility and flexibility
g. High mechanical strength

14. • Types of heating material:

15. • Applications:
1. Domestic purpose:
• Hot plates for cooking
• Room heaters
• Immersion heaters for water
heating
• Electric irons
• Electric toasters
• Electric ovens for baking etc.
2. Industrial purposes:
• Melting of metals
• Moulding of glass
• Heat treatment processes
• Baking of insulators
• Enamelling of copper wires etc.

16. • Advantages of heating:
1. Cleanliness
2. Absence of flue gases
3. Ease of control
4. Better working conditions
5. Ease of adaption
6. Very high efficiency of utilization
7. Uniform heating
8. Heating of non-conducting materials
9. Cheap furnaces
10. No limit to upper maximum temperature

17. • Conclusion:
The technical seminar topic discussed here is “Electric Heating”,
the heating is done conduction, convection and radiation ways. Under
these type of heating’s we saw resistance heating, arc heating and
electron bombardment heating with direct and indirect heating. And also
with induction heating and dielectric heating. Along with this heating we
saw central heating, electric heating, space heating and immerision type
heating. This heating is done for the quick process of the daily needful
things. These heating systems are used domestically and externally.
These are very useful in industries in order to increase the temperature of
the boilers, furnaces, and in traction purpose, electric iron box, water
heater both manual and automatic, room heating, in welding purpose,
floor heaters, etc.