1 Name of the faculty : V. Narsimha Reddy Designation : Lecturer in EEE Branch : E.C.E. Institute : GMR. Polytechnic Gajwel Year / Semester : VI Semester Subject : Electrical Utilization & Automation Sub. Code : EE605A Topic : Electric Heating Duration : 50 Mins Sub. Topic : Advantages and Requirements of Electric Heating Teaching Aids : PPT, Animation Revised By : K. Chandra Sekhar, L/EEE, GPT, HYD 9EE605A.11 Department of Technical Education Andhra Pradesh
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1 Name of the faculty: V. Narsimha Reddy Designation: Lecturer in EEE Branch : E.C.E. Institute : GMR. Polytechnic Gajwel Year / Semester : VI Semester.
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Name of the faculty : V. Narsimha Reddy
Designation : Lecturer in EEE
Branch : E.C.E.
Institute : GMR. Polytechnic Gajwel
Year / Semester : VI Semester
Subject : Electrical Utilization & Automation
Sub. Code : EE605A
Topic : Electric Heating
Duration : 50 Mins
Sub. Topic : Advantages and Requirements of
Electric Heating
Teaching Aids : PPT, AnimationRevised By : K. Chandra Sekhar, L/EEE, GPT, HYD
9EE605A.11
Department of Technical Education Andhra Pradesh
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Known to Unknown
• What is the necessity of heat in our lives?
• What is meant by electric heating?
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Objectives
On completion of this topic you would be able to know
• Electric Heating
• Advantages of Electrical Heating
• Requirements of Good Heating Element
• Materials for Heating Element
Introduction of Heating
• Heat plays an important role in everyday life
• Heat or fire and wheel are the basis for human
civilization
• Without fire and wheel, man wheel go back to stone age
• Man used fire to cook food
• In present days heat is used to extract the metals from
the ores
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Electric Heating
• Heat and electricity are interchangeable
• Heat can be produced by passing the current through a
conductor
• This method is superior compared to other methods
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Advantages of Electrical Heating
• Cleanliness
• High Efficiency
• No Pollution
• Localized Heating.
• Ease of Control
• Uniform Heating
Advantages of Electrical Heating
• Better working conditions
• Less floor area is required
• No carrying expenses
• Low attention and maintenance cost
• Economical
• Safety
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Contd…
Modes of Heat Transfer
The heat is transferred from a hot body are
• Conduction
• Convection
• Radiation
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Modes of Heat Transfer
Conduction• The heat transferred depends on the difference
between the temperature of the two points• The heat transfer by conduction takes place in solids,
liquids and gases• In solids, heat is transferred from one molecule to
adjacent molecule and so on• There is no actual motion of molecules
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Modes of Heat Transfer
Convection
• Heat is transferred from One point to the other point due to
motion of molecules .
• Heat dissipation: H = 3.875 (T1-T2)1.25 w/m2
• T1 = Temperature of the heating surface (0K)
• T2 = Temperature of the Air (0K)
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Radiation
• The heat transfer is confined to surfaces
• The radiant energy is emitted and absorbed by different