College】 【weak energy saving central air conditioning system for the analysis and summary --- Power By China's weak home 【Network】.

<br> <BR> Abstract: In 2005 the State to promote speed up construction of a conservation-oriented society, energy saving and become the focus of attention, so the application of energy-saving central air conditioning system control technology and the creation of conservation-minded society is significant. .In this paper, the key to the design of air conditioning control, air conditioning use in the process of energy conservation measures and management of three central air-conditioning, energy-efficient central air conditioning system was analyzed and summarized for the central air conditioning system to provide a meaningful view of energy saving .. .<BR> <BR> Keywords: central air conditioning; energy; measures <BR> <BR> Introduction With the economic and social development, central air conditioning in commercial and residential buildings of more and more widely, central air conditioning is a modern building .indispensable power running system. .Central air conditioning system to provide comfort to people living and working environment, but also consumed a lot of energy. .With the power and the number of devices increases, the energy consumption is also increasing. .According to statistics, China's building energy consumption accounts for about 30% of total energy consumption. In buildings with central air conditioning, central air-conditioning energy consumption accounts for 70% of the total energy consumption, and the trend of increasing year by year [1] .. Therefore, the central air conditioning system of energy-saving technologies is of great significance, in addition to emphasizing the use of functional, it should also attach importance to energy saving factor, lower investment and operating costs. .<BR> <BR> 1. The key to the design of air conditioning control <BR> <BR> 1.1 <BR> <BR> design control cooling and heating loads in the central air conditioning system construction design stage, the heat load and must be itemized by .when the cooling load calculation. .Dynamic load calculation method should be used according to actual load to choose the appropriate hot and cold sources. .Because the system cold and heat source and equipment performance in part load energy efficiency have a major impact on the system, therefore, selection of equipment on the one hand, taking into account the specific design conditions, the system should also be stressed operating conditions and part load .system performance. .<BR> <BR> Design load of hot and cold air-conditioning system design is too large, selection of equipment did not fully take into account the load characteristics of air-conditioning system and equipment performance, air conditioning unit capacity, pipe diameter, pump configuration, terminal equipment design is too large, resulting in .investment, operating cost increases. .Air-conditioning system and many buildings are lower than full capacity, even in the hottest month of the air conditioning units are still idle. .Pump selection is too large or too large pump motor power matching, low-efficiency operation, a waste of energy. .Parallel operation of multiple chilled water pump, no adjustments based on changes in cooling load the number of open sets, but no matter the size of the cooling load, cooling load is switched on by the largest chilled water pumps, wasted energy. .<BR> <BR> 1.2 Control of air conditioning water system design <BR> <BR> mostly constant flow water system, the design water flow rate at the maximum cooling load and the supply and return water temperature difference 5 ℃ determined. .The actual prevalence of a large flow of small temperature difference and the maximum load appears little time, most of the time in part load operation, the actual temperature is less than the design temperature difference, the actual flow ratio of 1.5 times the design flow rate, greatly exceed the design flow, .pump power consumption significantly. .<BR> <BR> Designers should pay attention to water system design, for each water loop for hydraulic balance calculation, significant differences between the circuits on the pressure to take effective measures to ensure the loop water balance, avoid water, heat imbalances ., proofread carefully and calculated parameters of air-conditioning water system, the practical implementation of the value of energy efficiency design standards, the use of electric two-way valve on the end of the flow through the air to control the flow rate changes with the load, and actively promote the variable frequency pumps, winter ., summer dual two-speed pumps and other energy-saving measures. .The results show that in recent years, increasing supply and return water temperature errands to reduce the energy consumption of delivery system is greater than the efficiency of the resulting decline in heat transfer equipment, the increase in energy consumption, so terms of the entire air conditioning system has a certain energy efficiency, not only to .eliminate the large flow of small temperature difference phenomenon, but also the gradual introduction of low flow, large temperature difference of the design. .Because of greater supply and return water temperature, equipment operating parameters change, the design should be determined through the technical and economic comparison. .Should also be concerned about the cooling water temperature on energy consumption of air conditioning systems. .<BR> <BR> (1) reduce the cooling water temperature <BR> <BR> the cooling water temperature is lower, cooler cooling coefficient is higher. .Supply cooling water temperature rise of 1 degree Celsius Austin, cooler COP has dropped by nearly 4%. .Reduce the cooling water temperature to the cooling tower need to strengthen the operation and management. .First, stop the cooling tower, its access to water valves should be closed. .Otherwise, as from the closure of the cooling tower water temperature is high, a mixture of cooling water temperature will improve the cooling coefficient cooler reduced. .Second, the cooling towers used for a period of time, should be timely maintenance, or the efficiency of cooling towers to fall, may not be sufficiently cool the cooling water. .<BR> <BR> (2) improve the chilled water temperature <BR> <BR> chilled water temperature is higher, cooler the higher cooling efficiency. .Chilled water supply temperature is increased by 1 degree Celsius cooler cooling coefficient can be increased by 3%, so do not blindly reduce the daily operation of chilled water temperature. .First of all, do not set too low cooler chilled water set temperature. .Second, be sure to close the stop valve to run cooler, take the bypass to prevent the part of the chilled water pipe, or, after running the water cooler will be reduced, leading to chilled water temperature is cooler down low .level. .<BR> <BR> 1.3 Design of new wind energy system <BR> <BR> the rational use of the new air system, you can effectively control energy usage. .To meet the sanitary conditions and reduce the need for fresh air or on the actual system with variable air volume adjustment. .A ventilation system, the use of indoor wind energy to preheat the new and pre-cooling treatment (ie heat recovery technology) and so can reduce the energy consumption of air conditioning systems. .<BR> <BR> 2. Air conditioning energy saving measures in the process of building air conditioning <BR> <BR> 2.1 Energy <BR> <BR> (1) the construction of rational design envelope. .Heat within the building can be cold room walls, doors and windows to pass the source, so the building envelope performance in the construction of energy-saving insulation plays an important role. .Especially the window structure, the control should be able to play the role of sunlight and to limit the size of the window wall; relatively large area for the windows of buildings should be considered heat-absorbing glass, heat-reflective glass or shading measures such as sun visor, roof, .EAVES, curtains to prevent heat absorption. .When the outdoor temperature can lower the air as the use of natural energy, so the construction of the window should be able to open or set to open in its natural ventilation openings. .<BR> <BR> (2) doors and windows to improve air tightness. .Especially in the summer, reducing the room air changes. .For example, the design can be used with good windows and doors closed. .Article is to raise additional doors and windows closed an important means airtight. .<BR> <BR> (3) for the cooling load of the larger buildings. .Its surface color of the light as well. .Periphery structure of the building design heat capacity of the material put on the outer sheath of the indoor side. .And the heat capacity of thermal insulation material on the outside of the small envelope to reduce heat storage load. .<BR> <BR> (4) choose a more reasonable indoor air parameters. .If the calculated parameters for the outdoor air setting, the summer air conditioning indoor air temperature and humidity, the lower calculation, room cooling load calculation of the greater, the greater the energy system. .Comfort requirements are met under the conditions of the summer to try to improve the indoor design temperature and relative humidity, to minimize the indoor winter design temperature and relative humidity, do not blindly seek to force the indoor air temperature is too low in summer, too dry, the winter indoor design temperature over .high. .<BR> <BR> 2.2 <BR> <BR> rational use of environmental factors when the outdoor temperature is lower (especially at night), pay attention to the room ventilation, use of shade during the day and pay attention to measures to try to close the doors and windows when the air conditioning energy conservation are all .consumption of effective measures. .<BR> <BR> 2.3 build intelligent systems control <BR> <BR> integrated system of intelligent control technology from time to time the central air-conditioning energy saving control system, is more effective electronic means of control. .Intelligent integration control system, especially the emergence of the module, reducing the threshold of technology in general should be based on the actual situation of building energy consumption, the use of intelligent integrated system of different control solutions to save energy. .It can be based on the actual operation of air conditioning, and automatic air conditioning operating parameters of the adaptive optimal regulator, to reduce energy consumption. .<BR> <BR> Same time, with the development of intelligent buildings, the establishment of a complete set of air-conditioning intelligent automatic control system is also indispensable, its air conditioning system plays a key role in the operation. .Air conditioning automatic control system despite an increase in investment, but can maintain a good indoor environment based on operating costs savings. .A well-designed and well-controlled operation management system can significantly save operational costs, to allow property owners to recover the investment within a short period of time can also improve the automated service quality, reduce the external environment. .<BR> <BR> 3. To strengthen the management of central air conditioning <BR> <BR> daily management is practical and effective central air-conditioning energy saving is the key. .No matter how good a design air-conditioning system, if managed properly, reach the same energy-saving purposes. .Energy for air conditioning purposes, the daily management of energy-saving measures include: <BR> <BR> (1) strengthen the training of air operators, to improve management quality. .Know how to change the parameters according to the outdoor reasonable and effective regulation. .Actively promote the water loop heat pumps, the use of heat recovery, variable air volume, variable volume systems, energy-saving technologies. .<BR> <BR> (2) strengthen the routine and periodic maintenance of equipment and systems to and washing. .Such as air conditioning components such as maintenance, condenser heat transfer surface of heat transfer equipment such as regular cleaning, or ash, filters, decontamination equipment cleaned regularly. .<BR> <BR> (3) Always check to automatic control equipment and instrumentation to ensure their normal work. .Operating parameters of the system to monitor, and never found in the normal operating parameters of system problems, a reasonable transformation. .Recurring equipment selection problem is too large, higher energy consumption. .Pre-cooling time as short as possible. .<BR> <BR> (4) When the transition to a cooling load of the indoor season when the outdoor air should be as far as possible the natural cooling capacity, savings in the amount of artificial cold cold source. .<BR> <BR> Central air-conditioning energy involved in a wide range of very wide, from the design of air conditioning, air conditioning installation and operation management and other aspects worthy of improvement. .In any case to improve energy efficiency, should come from improving energy efficiency measures taken to solve the problem, this is the way of scientific air conditioning energy. .<BR>.