含有磁效应混合纳米流体的自然对流式梯形腔的灵敏度分析:数值和统计方法
Sweety Khatun1, Rupa Kundu1, Saiful Islam1
1Department of Mathematics, Bangabandhu Sheikh Mujibur Rahman Science and Technology University, Gopalganj, 8100, Bangladesh.
Heliyon
|January 23, 2025
概括
这项研究分析了使用Ag-SiO2-H2O混合纳米流体在梯形腔中的磁动力学自然对流. 混合纳米流体增强热传递,但磁场减少它,为热器件提供设计见解.
科学领域:
- 计算流体动力学 (CFD) 是一种计算流体动力学.
- 热传递热量转移的方法
- 纳米流体 纳米流体
- 磁性水电动力学 (MHD) 是一个学科.
背景情况:
- 混合纳米流体,将SiO2和Ag纳米粒子与水相结合,对于先进的热工程和制造应用至关重要.
- 闭腔中的自然对流是一种基本现象,对各种工程设计有影响.
- 了解流体特性,几何和外部场的相互作用对于优化传热过程至关重要.
研究的目的:
- 为了数值地研究磁动力学自然对流传热传输在一个含有混合纳米流体 (Ag-SiO2-H2O) 的梯形腔内.
- 分析雷利数 (Ra),纳米粒子体积分数 (φ) 和哈特曼数 (Ha) 对热性能的影响.
- 开发用于预测传热速率的相关性,并评估系统对关键参数的灵敏度.
主要方法:
- 使用有限元法 (FEM) 模拟管理方程.
- 利用流线,等热量和线图来物理解释结果.
- 响应表面方法 (RSM) 用于可视化参数对响应函数的二维和三维影响.
主要成果:
- 与纯水相比,结合Ag-SiO2-H2O混合纳米流体的增强热传递率高达11.29%.
- 增加雷利数 (Ra) 有积极影响到热启动,而增加磁场强度 (Ha) 则减少了传热.
- 磁场 (Ha=25) 降低了2.4%的传热率,这表明流体增强和磁场抑制之间的权衡.
结论:
- 该研究提供了一个全面的热传递特征的理解在MHD自然对流下的混合纳米流体.
- 研究结果表明,优化纳米粒子度和控制磁场强度是设计高效的自然对流装置的关键.
- 开发的相关性为预测和优化类似系统的热性能提供了有价值的工具.
相关概念视频
01:18Magnetic Flux
3.5K
The magnetic flux measures the number of magnetic field lines passing through a given surface area. The SI unit for magnetic flux is the weber (Wb). Magnetic flux is a scalar quantity. It depends on three factors: the strength of the magnetic field B, the area through which the field lines pass, and the relative orientation of the field with the surface area.
Suppose a surface is divided into elements of area dA. For each element, the component of the magnetic field that is normal to the...
Suppose a surface is divided into elements of area dA. For each element, the component of the magnetic field that is normal to the...
3.5K
01:17Magnetic Damping
418
Eddy currents can produce significant drag on motion, called magnetic damping. For instance, when a metallic pendulum bob swings between the poles of a strong magnet, significant drag acts on the bob as it enters and leaves the field, quickly damping the motion.
If, however, the bob is a slotted metal plate, the magnet produces a much smaller effect. When a slotted metal plate enters the field, an emf is induced by the change in flux; however, it is less effective because the slots limit the...
If, however, the bob is a slotted metal plate, the magnet produces a much smaller effect. When a slotted metal plate enters the field, an emf is induced by the change in flux; however, it is less effective because the slots limit the...
418
01:30Typical Model Studies
337
Fluid mechanics model studies often utilize scaled-down systems to predict fluid behavior in full-scale environments, such as river flows, dam spillways, and structures interacting with open surfaces. Maintaining Froude number similarity in river models is crucial, as it replicates surface flow features like wave patterns and velocities.
337
01:31Magnetic Susceptibility and Permeability
945
In linear magnetic materials, like paramagnets and diamagnets, magnetization is proportional to the magnetic field intensity. The constant of proportionality, a dimensionless number, is called magnetic susceptibility. The value of the susceptibility depends on the type of material.
When diamagnetic materials are placed under an external magnetic field, the moments opposite to the field are induced. Hence, the susceptibility for diamagnets has a minimal negative value of 10-5–10-6. Since...
When diamagnetic materials are placed under an external magnetic field, the moments opposite to the field are induced. Hence, the susceptibility for diamagnets has a minimal negative value of 10-5–10-6. Since...
945
01:23Magnetic Field due to Moving Charges
8.4K
A stationary charge creates and interacts with the electric field, while a moving charge creates a magnetic field.
Consider a point charge moving with a constant velocity. Like the electric field, the magnetic field at any point is directly proportional to the magnitude of the charge and inversely proportional to the square of the distance between the source point and the field point. However, unlike the electric field, the magnetic field is always perpendicular to the plane containing the line...
Consider a point charge moving with a constant velocity. Like the electric field, the magnetic field at any point is directly proportional to the magnitude of the charge and inversely proportional to the square of the distance between the source point and the field point. However, unlike the electric field, the magnetic field is always perpendicular to the plane containing the line...
8.4K
01:13Torque On A Current Loop In A Magnetic Field
3.8K
The most common application of magnetic force on current-carrying wires is in electric motors. These consist of loops of wire, which are placed between the magnets with a magnetic field. When current flows through the loops, the magnetic field applies torque, which causes the shaft to rotate, thus converting electrical energy to mechanical energy.
Consider a rectangular current-carrying loop containing N turns of wire, placed in a uniform magnetic field. The net force on a current-carrying loop...
Consider a rectangular current-carrying loop containing N turns of wire, placed in a uniform magnetic field. The net force on a current-carrying loop...
3.8K