FORMS OF HEAT TRANSFER. CONDUCTION CONVECTION.

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CONDUCTION

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FORMSOF

HEATTRANSFER

CONDUCTION

CONVECTION

RADIATION

EVAPORATION

MEAN RADIANT TEMPERATURE

AIR TEMPERATURE AND MEAN RADIANT TEMPERATURE

AIR TEMPERATURE AND RELATIVE HUMIDITY

AIR MOTION

Relative Humidity: Relative humidity is a relationship between the amount of water vapor in a given mass of air in comparison to the maximum amount of moisture it could hold at that temperature.

Let’s look at an example:

If a liter of air contains 10 grams of water vapor and it could hold a maximum of 100 grams of water vapor at its present temperature, the relative humidity would be 10/100 time 100 or 10%.

As the temperature rises, the maximum amount of water vapor which can be held by a parcel of air will increase. Therefore if you were to raise the the temperature of this air, the relative humidity would drop.

PSYCHOMETRIC CHART

COOLING THE BODY

ADIABATIC HEATING / EVAPORATIVE COOLING

Dewpoint

If the air is gradually cooled while maintaining the moisture content constant, the

relative humidity will rise until it reaches 100%. This temperature, at which the

moisture content in the air will saturate the air, is called the dew point . If the air is cooled further, some of the moisture will condense.

COMPRESSIVE REFRIGERATION

COOLING PROCESS

COMPRESSOR -CONDENSER - EVAPORATOR

COOLING CYCLE

COMPRESSIVE REFRIGERATION SCHEMATIC

HEAT PUMP

BUILDINGSYSTEM

FORCED AIR SYSTEM

FORCED AIR HEATING

FORCED AIR DISTRIBUTION

DISTRIBUTION PATTERNS

RADIAL AND PERIMETER DISTRIBUTION SYSTEMS

RADIALPERIMETER

FURNACE LOCATIONS

HYDRONIC HEATING

RADIATORS

HOT WATER – ONE PIPE SYSTEM

HOT WATER – TWO PIPE SYSTEM

ELECTRIC HEATING

RADIANT HEATING