崇义Design and calculation of industrial coolers
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：本文围绕工业冷却器的设计与计算展开，阐述了工业冷却器在工业生产中的关键作用，其能有效地降低设备或工艺流程的温度，保障系统稳定运行，详细介绍了设计环节，包括依据不同的工业场景和冷却需求确定冷却器的类型，如风冷式、水冷式等，同时考虑冷却介质的特性、流量等参数，在计算方面，着重讲解了热负荷的计算方法，通过分析被冷却对象的热量产生速率、环境温度等因素，精准计算出所需的换热量，还涉及冷却器传热面积、传热系数等关键参数的计算，以确保冷却器能达到预期的冷却效果。
1、Design basis
Design Standard for Steel Structures GB50017-2017Steel Structure Design Manual, China Construction Industry Press, January 2004
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崇义Code for Construction and Acceptance of Steel Structures (GB50205-2020)
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崇义British Code for Design of Steel Structures (BS5950)
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2、Design load
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Load includes structural self weight, wind turbine constant load, live load, snow load, wind load, etc. The structural calculation adopts the ultimate stress method, therefore, the load value is larger than usual. The surface load is calculated based on the distribution coefficient and applied to the platform according to the line load. The wind load is calculated based on the wind vibration coefficient, body shape coefficient, and basic wind pressure to calculate the wind pressure values on four surfaces, which are then converted into line loads and applied to the columns. Auxiliary components such as stair handrails are applied to the stairs according to uniformly distributed loads.
1. Constant load
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崇义The self weight of the steel structure is automatically calculated by the program, and the node weight is considered based on the self weight of the structure multiplied by 1.3. The weight and fluid load of the radiator are applied by external forces.
崇义Platform constant load: 0.50kN/m2
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崇义2. Live load
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Live load of the platform for loading: 2.5kN/m2
崇义3. Snow load
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崇义According to relevant design data, the snow pressure can be basically calculated as 0.4N/m2.
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崇义4. Wind load
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崇义Calculate according to the maximum value.
Basic wind pressure: 0.35kN/m2, height variation coefficient of 1.8, wind vibration coefficient: 1.5, ground roughness category: Class A
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Is the standard value of wind load, is the wind vibration coefficient at height Z, is the shape coefficient of wind load, and is the coefficient of wind pressure height variation.
When the standard value of wind load is less than 0.75kpa, calculate based on 0.75 kPa and multiply by 1.4 times the safety factor. Namely
5. Temperature load
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The temperature difference is relatively small. The structural form is single, and the linear expansion of steel has a relatively small impact on the overall performance of the structure, which can be ignored.
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崇义6 Earthquake loads
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According to the seismic analysis design method: small earthquakes do not damage, medium earthquakes are repairable, and large earthquakes do not collapse. Small earthquake analysis can be divided into: bottom shear force method, response spectrum analysis, and elastic time history analysis. Medium earthquake analysis is calculated by multiplying small earthquake analysis by amplification factor.
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Seismic fortification intensity: 8 degrees
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Design basic seismic acceleration peak value: 0.3g
Construction site category: II site
Design grouping: Second group
崇义Damping ratio: 0.05
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崇义This structure adopts MIADS software for overall modeling and analysis. During modeling, beam elements are mainly used for each structure. In order to facilitate loading, plate elements are established at the structural platform. Consolidation is used as the boundary condition at the bottom of each column, and constraints are applied at the connection between the column and the original structure according to the actual situation. The structure includes upright column, cross brace, slant support and upper and lower platform steel structure.
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Load sub factors and load combinations:
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崇义Number 崇义 | load 崇义 | Partial coefficient remarks 崇义 | 崇义Partial coefficient remarks |
1 崇义 | 崇义dead load 崇义 | 1.3 | |
2 | Dead load, when it has a restraining effect on uplift and overturning | 崇义1.0 | |
3 崇义 | 崇义Dead load, when acting together with wind load and live load 崇义 | 1.2 | |
崇义4 崇义 | 崇义Live load | 1.6 崇义 | |
崇义5 崇义 | 崇义Live load, when combined with wind load 崇义 | 1.2 崇义 | |
6 | 崇义Wind load 崇义 | 1.4 崇义 | |
崇义7 | When combined with wind load and live load | 1.2 崇义 |
崇义3、 Radiator calculation
崇义1. Material parameters
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崇义Aluminum alloy adopts 6005-T1, with tensile strength and yield strength equivalent to 6063-T5, tensile strength ≥ 150Mpa, yield stress ≥ 110 Mpa. According to the performance table of aluminum alloy, it is found that 6063-T5 has a tensile strength of 185Mpa, yield stress of 145 Mpa, and fatigue strength of 90MPa.
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2. Working condition analysis
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The calculation of radiators can be divided into 1. lifting ondition,
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4.support and lifting point participate in force simultaneously.
崇义5.support bears gravity, while lifting point bears horizontal force.
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崇义6.support does not bear any force, that is, when the overall structure is subjected to uneven settlement, there is a suspension at the bottom)
崇义To ensure its stability, it is recommended that the foundation treatment should be pre compressed and settlement assessment should be carried out during the overall installation.
2.1 Hoisting conditions
At this point, the radiator is only considered for its own weight due to the lack of fluid injection, and is lifted and installed through a side lifting point. Because no other accessories were installed during modeling, in order to estimate the weight more accurately, its self weight coefficient was defined as 1.3.
崇义The radiator structure consists of 1, frame 2, support beam 3, heat exchange tube 4, tube plate, and other ancillary structures. As the heat exchange tube and support beam are fixed together through a corrugated plate, it can be considered that the heat exchange tube participates in the structural stress, which leads to strain and stress generation.
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The overall structural model is
崇义Radiator structural model
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崇义The overall deformation of the radiator during the lifting process
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Stress cloud diagram of radiator during lifting process
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From its displacement cloud map, it can be seen that its overall deformation is 1.2mm, and the maximum stress is 15MPa
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崇义Stress cloud map of heat sink
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崇义Displacement cloud map of heat sink
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From its displacement cloud map, it can be seen that its overall deformation is 1mm and the maximum stress is 2MPa. Through calculation, it can be seen that horizontal lifting has little effect on the heat dissipation fins, and its deformation and stress are far less than the standard requirements.
崇义The vertical lifting situation is as follows:
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崇义Vertical lifting stress cloud map
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