额敏Design and calculation of industrial coolers
：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。
额敏1、Design basis
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额敏Design Standard for Steel Structures GB50017-2017Steel Structure Design Manual, China Construction Industry Press, January 2004
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额敏Code for Construction and Acceptance of Steel Structures (GB50205-2020)
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额敏British Code for Design of Steel Structures (BS5950)
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2、Design load
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.
额敏1. Constant load
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额敏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.
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Platform constant load: 0.50kN/m2
额敏2. Live load
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Live load of the platform for loading: 2.5kN/m2
额敏3. Snow load
额敏According to relevant design data, the snow pressure can be basically calculated as 0.4N/m2.
额敏4. Wind load
额敏Calculate according to the maximum value.
额敏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.
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额敏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
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额敏5. Temperature load
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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6 Earthquake loads
额敏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.
额敏Seismic fortification intensity: 8 degrees
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额敏Design basic seismic acceleration peak value: 0.3g
额敏Construction site category: II site
额敏Design grouping: Second group
Damping ratio: 0.05
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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.
Load sub factors and load combinations:
Number 额敏 | load 额敏 | Partial coefficient remarks 额敏 | Partial coefficient remarks 额敏 |
额敏1 | 额敏dead load | 额敏1.3 | |
2 | Dead load, when it has a restraining effect on uplift and overturning 额敏 | 1.0 | |
3 额敏 | 额敏Dead load, when acting together with wind load and live load | 额敏1.2 额敏 | |
4 | 额敏Live load 额敏 | 额敏1.6 | |
5 | 额敏Live load, when combined with wind load | 额敏1.2 | |
6 额敏 | 额敏Wind load 额敏 | 1.4 额敏 | |
7 | 额敏When combined with wind load and live load 额敏 | 额敏1.2 |
额敏3、 Radiator calculation
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额敏1. Material parameters
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额敏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
额敏The calculation of radiators can be divided into 1. lifting ondition,
3. operating condition (operating condition is divided into
额敏4.support and lifting point participate in force simultaneously.
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额敏5.support bears gravity, while lifting point bears horizontal force.
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额敏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)
额敏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
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额敏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.
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
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Radiator structural model
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额敏The overall deformation of the radiator during the lifting process
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额敏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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Stress cloud map of heat sink
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Displacement cloud map of heat sink
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额敏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.
额敏The vertical lifting situation is as follows:
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Vertical lifting stress cloud map
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