• Share
  • Email
  • Embed
  • Like
  • Save
  • Private Content
070716 Warmterras Nl

070716 Warmterras Nl



Introduction to Infrared heating principles

Introduction to Infrared heating principles



Total Views
Views on SlideShare
Embed Views



8 Embeds 2,924

http://www.eenwarmterras.nl 2829
http://www.horecaimage.com 85
http://eenwarmterras.nl 3
http://www.eenwarmterras.be 2
http://www.slideshare.net 2 1 1
http://www.linkedin.com 1



Upload Details

Uploaded via as Microsoft PowerPoint

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
Post Comment
Edit your comment

    070716 Warmterras Nl 070716 Warmterras Nl Presentation Transcript

    • Introduction to Infrared heating principles
      • Frederic Marrot – Induction training 2005
      Philips Special Lighting IR
    • What is Infrared ?
    • How to heat an object ? Physical possibilities: 1. Conduction 2. Convection 3. Radiation
    • Conduction Heat transfer is made through direct contact from the source to the object (receiver). E.g.: boiled eggs in hot water, coffee pot on a warming plate Source (s) Ts: high Receiver (r) Tr: rises
    • Convection Heat transfer is carried out via flow of liquid or gas, primary heated by a source. E.g. central domestic heating, household oven Tt: low Tt: low Tt: high Source (s) Ts: high Receiver (r) Tr: rises Transfert medium (t)
    • Radiation Heat transfer occurs via radiation emitted from source at high temperature. Surrounding objects in this area are absorbing the radiation. E.g. the sun, infrared lamps Source (s) Ts: high Receiver (r) Tr: rises
      • Reaching an object, radiant energy can either be:
        • reflected,
        • absorbed or
        • transmitted (through the material)
      • Reflection, absorption or transmission of radiant energy by the object depends on:
        • Infrared heating source specifications such as wavelength / frequency
        • object properties : colour, thickness, material, surface...
      Interactions of radiation with an object
      • Design for infrared heating system must take into consideration:
        • the heating source specifications
        • the object properties
        • the application features
      • Design of an infrared heating system can only be made if all above characteristics are known.
      Designing an Infrared heating system
      • UV Visible radiation IR
      IR within the electromagnetic spectrum Treatment Eye supporting Warmth/ UV-sensitive functions heat materials transport
    • The infrared wave band UV radiation Visible radiation IR-A IR-B IR-C 800 nm 0.8  380 nm 0.38  1 400 nm 1.4  3 000 nm 3  10 000 nm 10  3620K 2070K 965 K 290 K Short- Medium- Long-waves
      • The heating effect is due to the infrared part of the optical spectrum.
      • Infrared energy comprises of three parts:
      • - IR-A short - waves,
      • - IR-B medium - waves,
      • - IR-C long - waves,
    • Classification:
      • short wave
      • medium wave and
      • long wave
      • emitters are available.
    • Examples of short wave infrared emitters Incandescent tungsten lamp Halogen lamp
    • Examples of long wave emitters Metal resistance Ceramic resistance
    • Spectral power distribution of different IR emitters
    • Comparison of short, medium, long wave emitters 0.05% 10% 30% 60% 1.5% 20% 50% 28.5% 6% 46% 44% 4% Visible IR-A IR-B IR-C 4.0 µm 2.2 µm 1.2 µm Emission peak 5 mn 30 sec 1 sec Swith ON/OFF time (90% efficiency) 40 % 60 % 92 % Radiant efficiency Fe-Cr-Alalloy coil in closed steel tube Fe-Cr-Alalloy coil in quartz tube Tungsten coil in sealed quartz tube Material Resistance Quartz emitter Halogen lamp Emitter Long wave Medium wave Short wave Infrared waves
    • Comparison of short, medium, long wave emitters The more the source is hot, the more it emits in the short wavelength. When the colour temperature decreases, the maximum of emission moves towards longer wavelengths Low Medium High Color sensitivity Low Medium High Brightness Hardly not relevant Possible Good focusing recommended Focusing with reflectors Yes, very high Yes No Air draughts sensitivity Convection Radiation and convection Radiation Heating principle 800 K 1 300 K 2 450 K Color Temperature Long-wave Medium-wave Short-wave Infrared-waves
    • Conclusion – Emitters’ comparison
      • Infra R ed emitters (heat sources) radiate their energy over a range of wavelengths.
      • Their spectral power distribution depends on the temperature and emission properties of the radiator.
      • Medium and long wave emitters (e.g. steel tube and ceramic radiators) have a higher thermal inertia and lower temperature than short wave radiators, like InfraRed lamps.
    • Benefits of short wave infrared lamps Benefits Features Instant heat > 90% emission within 1 second Clean No emission by products, no pollution Safe Quartz envelope, heat shock resistant Economical > 85% of consumed energy transmitted into infrared heat Fully dimmable Fully controllable accurately (0 to 100%) Possibility to put On/Off switches do not affect life time of the lamps people sensor Low maintenance Long life: 5 000 hours Heat can be focused Same optical properties as light, can be directed by reflectors Compact heater Compact heat source, narrow diameter of lamps
    • InfraRed halogen lamp
      • InfraRed Business Line
      • December 2003
    • InfraRed halogen lamp Quartz tube Cap base Cable Inert gas + halogen Tungsten filament Exhaust tube Filling tip
      • Why halogen filling gas ?
        • Long life time
        • minimized filament evaporation
      • Why quartz tube ?
        • Withstanding high temperatures
        • Heat shock resistancy
        • transparent to Infrared radiation
      • Why tungsten filament ?
        • Fast time response
        • Very high melting point of 3400°C
      Halogen lamp construction
    • The halogen cycle: Quartz tube Tungsten filament Halogen molecules Cold part >250°C Hot part > 1000°C
    • Tungsten-halide molecule formation Tungsten molecule evaporation Tungsten molecule dissociation The Halogen cycle The halogen cycle 1 4 3 2
    • Burning position
      • In general, quartz halogen lamps should be used horizontally.
      • For a vertical burning position and in case of strong vibrations, special lamps - indented lamps - are produced where filament supports are fixed in the quartz bulb and some changes are made to the filling gas.
    • Tungsten filament
      • Fast time response
      • Very high melting point of 3400°C
      • Compact source
      Single coil Coiled coil
    • Halogen lamp construction : Pinch
      • Pinch temperature must not exceed 350°C, otherwise
      • Molybdenum foil starts to be oxidised
      • Cracks in the pinch : leaky lamp
      • Oxygen enters in the bulb : short life time
    • Working temperatures
      • Pinch temperature:
        • below 350°C to avoid early oxidation of the molybdenum foil (leakage)
        • pinch temperature has to be measured with thermocouples fixed by the lamp manufacturers according IEC norms
      • Tube temperature:
        • minimum 250°C for the halogen cycle
        • maximum 900°C for industrial halogen lamps,
        • maximum 800°C for HeLeN and Stela
        • to avoid structure change (crystallization)
    • Response time
    • Comfort Heating Professional & Patio
    • Comfort heating
      • Terraces, patio
      • Hotel rooms
      • Barbecues
      • Churches
      • Factory workshop
      Philips InfraRed lamps are used for in & out-door heating:
    • Comfort heating
      • Benefits of halogen lamps:
      • heat only where needed, when needed
      • visual and instant response
      • energy saving
      • clean and safe, no gas pollution
    • Comfort heating – the range
      • For Zone-heating applications, Philips propose:
      • the Unique non glare HeLeN lamp for professional or outdoor heating
      Range HeLeN Shape Straight Power 500W - 3000W Finish HeLeN glare reduction Life time 5.000 hours
    • HeLeN: Infrared Halogen Lamp Unique Philips solution with high heat efficiency and low glare emission
    • HeLeN : More compact, better colour rendering. Ruby sleeve lamp HeLeN lamp
    • How Philips HeLeN Infrared lamps work:
      • Infrared Halogen lamp :
        • Special filament design delivering direct heat (short wave)
        • Quartz tube resistant to heat shock
      • Special HeLeN coating
        • Reduce glare
        • Nice colour rendering
        • Filter visible light, not the heat emission
      • Horizontal or vertical burning availability
      • Various caps
      • Exclusive solution from PHILIPS
    • HeLeN : Best Spectral distribution with low glare level