Transcript Prezentace aplikace PowerPoint

Heating and Cooling
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Coordinator:
Karel Kabele, [email protected], CTU in Prague
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Contributors:
Eric Willems, Erwin Roijen, Peter Op 't Veld, [email protected]
Camilla Brunsgaard, [email protected] & Mary-Ann Knudstrup, [email protected], Aalborg
University, Per Kvols Heiselberg, [email protected], Tine S. Larsen, Olena K. Larsen, Rasmus Lund
Jensen (AAU)
Arturas Kaklauskas, [email protected], Audrius Banaitis, [email protected] ,
Vilnius Geniminas Technical University (VGTU)
Marco Perino, [email protected], Gianvi Fracastoro, Stefano Corgnati, Valentina Serra
(POLITO)
Werner Stutterecker, [email protected], (FH-B)
Mattheos Santamouris, [email protected], Margarita Asimakopoulos, Marina Laskari,
[email protected], (NKUA)
Zoltan Magyar, [email protected], Mihaly Baumann, Aniko Vigh, [email protected] (PTE)
Manuela Almeida, [email protected], Sandra Silva, [email protected] , Ricardo Mateus,
[email protected], University of Minho (UMINHO)
Piotr Bartkiewicz, [email protected], Piotr Narowski, [email protected]
(WUT)
Matthias Haase, [email protected], (NTNU)
Karel Kabele, [email protected], Pavla Dvořáková, [email protected], (CTU – FCE)
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LECTURE 3
ACTIVE SPACE HEATING AND COOLING
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Heat emitters (radiators, convectors, tubular, radiant heating
(stripes, panels), dark and light infrared radiant pipes,
stoves).
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Heating equipment
• Heat source - heat transfer medium
- heat emitter
• Classification of the systems
– local
– floor
– central
– district
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Heat emitters
Heat emitters
Convectors
Radiators
Banks of Pipes
Fan convectors
Natural
Off peak storage
Columns
Radiant
panels
Panels
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Convectors
Natural
Fan-convectors
Floor
Wall
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Radiators
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Control limits
Large mass = heating unresponsive
low mass = responsive heating
Mass = storage
Responsive heating
control important
to make use of
solar gains
Water content
radiator
G radiator G
Panel radiator
P
today
Heat insulation (old
buildings)
Heat insulation
standard 1995 (new
buildings)
Steel radiator
S
Heat insulation
Standard 2000
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Thermal output
* radiator temperature, 200C room temperature
Convection share
Radiation share
Single panel
radiator, without
convector
Radiator
(modular)
Double panel radiator,
with three convectors
Finned tube
convector
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Off-peak storage
• Static
• Dynamic
• Convector
• Radiator
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Air flow patterns
prof.Ing.Karel Kabele,CSc.
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Radiant panels
• Low temperature
• heaters max 110 °C (water, steam, el.power)
• High temperature
• dark - about 350°C - radiant tube heating system
(gas)
• light - about 800 °C - flameless surface gas
combustion
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Heat emitters
• Design principles
– Heating output
– Location
– Covering - furniture
– Connection to the pipe system
– Type
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Heat emitters design
• Covering = changes in the output
100%

95%
110%
87%
Connection to the piping system
100%
100%
90%
85%
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SPACE HEATING AND COOLING
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Low-temperature radiant heating
High-temperature radiant cooling
• Underfloor, wall and/or ceiling
heating/cooling
• Embeded surfaces
• TABS
• Snowmelt systems
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Low - temperature radiant heating
• floor, wall and/or ceiling with embedded pipes or
el.wires in concrete slab
– Temperature distribution
Underfloor heating
Radiators
Ideal
temper
ature
Ideal
temper
ature
Underfloor
heating
125BEE1_2008/2009
prof.Ing.Karel Kabele,CSc.
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Radiators
Radiant heating/cooling
• Output
– Limited surface temperature limited output cca 100
W.m-2
• Energy savings
– Lower air temperature lower heat losses
• Control
– Low temperature difference autocontrol effect
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Underfloor heating
• History
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Low/high - temperature
radiant heating/cooling
• Floor structure
Insulating strip between wall and flooring
Finished flooring
Concrete slab min 65mm
Reinforcement
Pipes
Thermal insulation
20-80mm
Supporting floor structure
Humidity seal
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Underfloor heating - structure
TYP B
TYP A
TYP C
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Low - temperature
radiant heating
• Technical solution
– Pipe layout
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Underfloor heating - examples
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Wall heating
• Embedded pipes - inner wall side
• Higher surface temperature on both
sides
• Furniture layout
• Rooms with given use of space: swimming
pools, entrance areas, corridors
• not possible or desirable to use conventional
heating surfaces: prisons, hospitals,…
• Possibility to use the system for cooling
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Wall heating - Design process
• determination of the areas, applicable to this type of heating;
• determine the desired maximum surface temperature;
• calculate the heat loss room analogy for underfloor heating
without losing the wall with wall heating;
• verification of the achievable performance of surfaces and
temperature
• compared to heat loss, or draft supplementary heating
surfaces.
• select the type of wall heating, wet or dry system, pipe or
capillaries;
• design spacing and temperature parameters of heat transfer
fluid;
• hydraulic calculation.
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Wall heating - temperatures
• From the point of thermal comfort it is like radiators heating
• Maximum surface temperature 35 - 50 °C according to local
conditions.
• For surface temperatures above 42 ° C can be painful contact.
• size of losses to the outside, impact on the neighboring room
• Some manufacturers recommend and design system for the
surface temperature of 35 ° C
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Technical solution
A – pipes diameter 10-14 mm
• Wet
• Dry
B – capillary mats
Pipes diameter 6 mm , rozteč 30-50 mm
• Wet
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Thermally Activated Building Structures (TABS)
• With or without phase change material
• Cooling capacity can limit the use of system
• Control of room conditions?
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Thermal activation of building structure (TABS)
- National technical library (Prague)
foto: Václav Nývlt, Technet.cz
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Special case
HEATING OF THE BASEMENT OF ICE SURFACE
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Realization
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„Floor“ structure
Ice 50 mm
Concrete 240 mm
Cooling -16/-12°C;
160 W/m2
EPS 250 mm
Concrete 250 mm
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„Floor“ structure with heating
system
Ice 50 mm
Concrete 240 mm
Cooling -16/-12°C
160 W/m2
EPS 250 mm
Concrete 250 mm
Heating 10/8 °C;
cca 10 W/m2
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Heating of outdoor surfaces
Snowmelt system
Pipe spacing 15-50cm
Temperature 50-80°C
Use of antifreeze
Thermal output according to the amout of snow
and outdoor temperature
Large thermal inertia
Mechanical resistance
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• Air heating/cooling systems – circulating, ventilating.
• Integration of heating/cooling systems.
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