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