Cooling is achieved by extracting heat from space. The heat may be extracted by:a). Supplying air at...

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Cooling is achieved by extracting heat from space. The heat may be extracted by:a). Supplying air at a temperature lower than that of the room, i.e. a Convective Cooling system, or:b). Introducing a cool surface in the room which exchanges heat by convection and radiation with the room, i.e. a Combined Cooling System.The heat removed from the room by the cooling system can be represented as a negative heat gain.A . For a convective cooling system with a cooling capacity ‘ ’, the formula developed to calculate the dry resultant temperature when the heat gains are and can be modified as:to allow for a convective cooling load, .Allowing for the correction of the external temperature, being rather than during the summer, the Convective Cooling Load for operative temperature control for steady state conditions.
	
Document Preview: Air Conditioning Cooling loads.Steady State Cooling Loads (24-hour average)Cooling is achieved by extracting heat from space. The heat may be extracted by: a). Supplying air at a temperature lower than that of the room, i.e. a Convective Cooling system, or: b). Introducing a cool surface in the room which exchanges heat by convection and radiation with the room, i.e. a Combined Cooling System. The heat removed from the room by the cooling system can be represented as a negative heat gain. A . For a convective cooling system with a cooling capacity ‘ ’,  the formula developed to calculate the dry resultant temperature when the heat gains are  and can be modified as:                                    to allow for a convective cooling load, . Allowing for the correction of the external temperature, being  rather than during the summer, the  Convective Cooling Load for operative temperature control for steady state conditions.Steady state Convective Cooling load (Operative point control)			Air conditioning systems are normally controlled from the Air Point Temperature (using air temperature sensors rather than operative temperature sensors which are more expensive and not as reliable. Steady State Convective Cooling Load for air temperature control is given by: 				Where: B. Steady State Combined Convective and Radiant Cooling systems: Consider a cooling system such as a chilled ceiling, where the cooling is partly convective and partly radiant. Assume that the plant capacity is  and that the proportion of the radiant cooling is R. By expressing  and  in terms of  and R we get: The radiant component of is: XXXXXXXXXXand The convective component of is: Hence the heat removed from the environmental point is: And the heat removed from the air point is:                                                                                        XXXXXXXXXXor:      Using the equation: And by allowing for the heat removed from the...

Robert · Accepted Answer

Solution: 
Design for Internal Heat gains:
New projects usually take at least 2 to 3 years from preliminary sketch design to 
handover. During this period the initial design strategies can become gradually 
compromised by subsequent decisions and changes. They may be gradually 
diluted as different personnel get involved, through evolution of the brief, cost 
cutting, or merely a lack of understanding of the strategic issues by the team as a 
whole. Reported examples of this include background lighting levels shifting 
towards general lighting levels, and localised switching forgotten during fitting 
out. A method of monitoring the design targets is therefore recommended. This 
could mean having somebody who is not otherwise involved in the project come 
in every few months (or more frequently at certain stages of the design) to review 
the design against the original criteria.

Cooling is achieved by extracting heat from space . The heat may be extracted by: a). Supplying air at a temperature lower than that of the room, i.e. a Convective Cooling system, or: b). Introducing...

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