College】 【weak central air-conditioning design in order..

<br> design sequence: first at the end, after the host <BR> design principles: reasonable economic and operating cost savings to maximize design and application <BR>: <BR> one end of the section: < .BR> 1, fan coil. management system; <BR> Scope: general office, restaurant and other places <BR> 2, fan coil plus fresh air system; <BR> Scope: demanding office, hotel, catering and entertainment .establishments <BR> 3,. Full air system; <BR> Scope: supermarkets, workshops and other places <BR> two large bays, the host part: <BR> 1, screw chiller refrigeration, municipal or boiler heating .; <BR> Scope:. a dedicated room, adequate power, need special duty <BR> 2, air-cooled refrigeration unit (heating), municipal or boiler heating; <BR> scope: air conditioning, small size, .there is no room, no special duty <BR> .3, the centrifugal chiller refrigeration, municipal or boiler heating; <BR> scope: the larger air-conditioning, a dedicated room, adequate power, need special duty <BR> .; 4, lithium bromide refrigeration unit (heating), municipal or. boiler heating; <BR> Scope: lack of electricity, heat and after a comprehensive comparison of municipal economy, a dedicated room, need special duty <BR> Third, .other: <BR> 1, a multi-system drag; <BR> for. Range: smaller air-conditioning, no special room, no special duty, air conditioning, but not at the same time larger and the need to use .separate accounting and other places <BR> 2, air duct machine system; <BR> Application: large room, no. Private room, no special duty, flexible control, low initial investment <BR> design process: <BR> .; one end of the section: <BR> (a) the selection of equipment: <BR> 1, calculate the actual air-conditioned area; <BR .> 2, according to site of use to determine cooling load .indicators, designed to calculate the total load, depending on the device layout features to determine the number of devices required to determine the device model; <BR> cooling load budget targets: <BR> <BR> <BR> of .combination. air conditioner, cycle 6 to 7 times the number of shopping malls, it is recommended 8 to 9 times <BR> (b) of the water system design: <BR> 1, positioning equipment, layout, determine the location .of the riser, the complexity of the system using the same program or to determine. different programs (when the riser and the terminal equipment from more than 30 m using the same program as far as possible); <BR> 2, to determine .the main channel, and a reasonable connection with the device, when the head of a branch road to the regulator valve should be located;. <BR> 3, depending on the device for each pipe to determine flow rate of water flow, water .flow rate and then calculated according to the design diameter; <BR> 4, the design flow rate of air conditioning water 0.9-2.5m / s, the greater the diameter, flow rate more. large pipe than the friction should be less than .500; <BR> 5, pipes and equipment connected, then into the water on the set of soft, filters, valves, outlet pipe, then set the soft, valve; <BR .> 6, the condensed water pipe diameter .design: <BR> When the unit cooling load Q ≤ 7KW, DN = 20; Q = 7.1-17.6, DN = 25; Q = 17.7-100, DN = 32; Q = 101-176,. DN = 40; .Q = 177-598, DN = 50; Q = 599-1055, DN = 80; Q = 1056-1512, DN = 100; Q = 1513-12462, DN = 125; Q> 12462, DN = .150 < .BR> 7, air-conditioning pipe insulation: <BR> when using ultra-fine glass wool insulation shell, the supply and return water pipes with insulation thickness of 50mm, the thickness of condensate pipe insulation using 30mm; <BR> when .using the rubber material. insulation, the supply and return water pipes with insulation thickness of 30mm, the thickness of condensate pipe insulation using 15mm; <BR> When the cooling water pipes and other PVC plastic pipe used, the time to make thermal insulation ... Fluoride system should be delayed and more heat.. <BR> (C) Wind Design: <BR> 1, air flow options: <BR> (1) of new wind conditions: determine the minimum fresh air per .person <BR> theaters, museums, stadiums, shops, each of the new minimum. wind 8M3 / H; <BR> office, library, meeting rooms, restaurant, dance hall, general wards, each of minimum fresh air 17M3 / .H; <BR> rooms, each minimum fresh air 30M3 / H, normal use of 50M3 /. H; <BR> (2) return air conditions: determined by the number of cycles, and generally 8-10 times / H ., the air space volume × (8-10) / H <BR> 2, the choice of fan pressure:. <BR> estimation method: pressure = (most unfavorable loop length × 10) Pa <BR> 3, .device location, as close to the water system riser; <BR> 4, arrangement of air, no air conditioning in the dead zone to ensure that the premise of. Next, to minimize the amount of air to maintain uniform air specifications; outlet .velocity in 2-2.5m / s between the return air speed in the 3-5m / s between the air flow under the air vent and the wind speed to determine size; <BR> 5., to determine the main air duct and .a reasonable connection with the outlet, when the head of a branch road should be located so as to adjust the valve, and each outlet are equipped with air volume control valve; <BR> 6, determined according to the number of air duct sections .. air volume, and then calculated according to the design anemometer duct cross-sectional area, the installation space to determine duct size, the decoration in the elevation of the premise of ensuring to minimize the aspect ratio duct to minimize the adjustable; <BR> .; air ventilation and air conditioning. Pipe design flow (m / s): <BR> <BR> Note: 1, the table elements are recommended flow rate, the denominator is the maximum flow rate.. <BR> 2 ., there are strict requirements on the system, muffler, pipe flow velocity should not exceed 5m / s, the flow rate within the branch should not be greater than 3m / s.. <BR> 7, when the air duct through the engine .room or fire district, the air paths should be set up fire control valve; <BR> 8, when the fan air is greater than 10000M3 / H, the fan static pressure box silencer import and export should be set by. plenum section rate .was 2-3m / s; less than 10000M3 / H, in the fan outlet silencer can set, muffler the same diameter and the main air duct; <BR> 9, steel air duct insulation:. When using ultra-fine glass wool .board <BR> insulation, the insulation thickness of 40mm; when using the rubber sheet insulation, the insulation thickness of 15mm.. <BR> Second, the host part: <BR> (a) of the cooling and heating Host .: <BR> use the site to determine load estimates based on indicators, and then multiplied by the total area of air-conditioning equipment can calculate the total load, then the system. situation to determine the number of hosts, select device models; .for some multi-purpose air-conditioned premises, computing devices while taking advantage of the load factor to be considered.. <BR> Budget targets air-conditioning load of the host: <BR> <BR> <BR> .(b) of the cooling tower: <BR> refrigeration unit according to the required cooling water to determine the actual amount of water used in cooling towers should be greater than the required amount of water,. should be noted that the working conditions of .the cooling tower cooling water should be and crew working conditions consistent.. <BR> (C) of the refrigerant pump: <BR> 1, number: more than one unit as a standby; <BR> 2, flow rate .: according to the unit water flow × (20 ~ 30)% OK; <BR> 3,. Head: According to the system, usually take (20 ~ 40) m; <BR> (d) cooling water pump: .<BR> 1, number: more than one unit as a standby; <BR> 2, flow rate: According to the cooling unit. water flow × (10 ~ 15)% OK; <BR> 3, head: .According to the height of the water pumps and cooling tower units + drop + (5 ~ 10) m; (e) soft water equipment: <BR> according to traffic. OK, usually taken (3 ~ 8) M3 / H < .; BR> fill pump flow rate should be based on the normal water supply to determine the amount of recharge water and the accident and are advised to 4-5 times the normal water supply.. Generally based on normal supply of water to 1% of .water capacity of the system considered.. The preliminary design can be estimated 1% of circulating water.. Water supply pump supplies water flow is normal water supply + accident; and the flow of water treatment equipment can be determined in accordance with normal supply of .water, or 1%.. <BR> Fill water system load can be estimated in accordance with: the design of cold-based, system water capacity is about 2-3L/KW.. Useful floor area to estimate, about 1 liter .per square <BR> (VI) to soften the water tank: <BR> according to the standard tank size is usually taken (2.5 ~ 8) M3 <BR> (g) floor expansion tank: <BR> 1 .., tank diameter is usually taken: Φ1000 ~ 1200 <BR> 2, with 2 sets of pumps: <BR> traffic: (3 ~ 8) M3 / H; head: (refrigerant pump lift × 1.3) m < .BR> (h). points, catchment, sub-cylinder: <BR> 1, the diameter D = (1.5-3) × branch in the maximum diameter, mm <BR> 2, the length of the valve according to .the number and type of branch pipe to determine <BR> (IX). cooling water treatment: <BR> usually cooling water inlet of the unit an electronic water treatment device for processing.. <BR> Generally constant pressure central air .conditioning system located in the freezing point of the return water pump inlet pipe, which can produce the pressure head the pump in the system get the right distribution.. Constant pressure heating and air conditioning system of the present way of pay constant pressure expansion tank main .pay, pay constant pressure water supply pump, constant pressure gas tank with supply water at constant pressure water supply pump and so on.. Which supply water at constant pressure expansion tank is the most economical and simple way, so now widely used in civil construction ., but the expansion tank must be the highest point in the system.. <BR> <BR> <BR> <BR>..