在使用多个案例神经网络实时估计3D血管流体动力学的物理信息约束的作用
Wei Xuan Chan1, Wenhao Ding1, Binghuan Li2
1Department of Bioengineering, Imperial College London, Exhibition Road, London, SW7 2AZ, United Kingdom.
Computers in biology and medicine
|March 27, 2025
概括
监督神经网络 (SN) 准确地预测血管中的血液流动动态,在稳定和脉动流动方面表现优于物理信息的神经网络 (PINNs),为传统模拟提供更快,更有效的替代方案.
科学领域:
- 生物医学工程 生物医学工程
- 计算科学 计算科学
- 流体动力学 流体动力学
背景情况:
- 血管流体动力学的数值模拟对于生物医学研究和临床应用至关重要,例如预测动脉疾病.
- 传统的计算流体动力学 (CFD) 模拟是耗时的,阻碍了临床采用.
- 开发有效的实时流量预测方法是必不可少的.
研究的目的:
- 研究多个案例神经网络 (NN) 在3D曲线管中实时预测流体动力学的有效性.
- 为了比较物理信息神经网络 (PINN) 与在CFD数据上训练的监督网络 (SN) 的性能.
- 确定提高NN在模拟血管流量的准确性和效率的策略.
主要方法:
- 采用多个案例的神经网络 (NN) 来预测狭窄的3D曲管中的稳定和脉动的流量.
- 将无监督PINN与使用广泛的CFD模拟训练的监督网络 (SN) 进行比较.
- 实施的策略包括坐标参数的二次NN,硬壁边界条件和脉冲流的光谱编码.
主要成果:
- 多个案例的PINN在稳定流量 (误差<2-5%) 实现了准确的结果,具有特定的增强功能,但在脉动流量方面失败了.
- 监督网络 (SN) 为各种几何体的稳定和脉动流提供了高度准确的预测 (误差<1%).
- 与PINNs相比,SNs的培训计算成本明显较低.
结论:
- 监督的神经网络是比PINNs更有效和计算效率更高的实时预测复杂的血管流体动态的方法.
- 这项研究强调了基于物理学的方法在这个特定应用中的局限性.
- 优化的SNs为加速流体动力学模拟的临床采用提供了有希望的解决方案.
相关概念视频
Accelerating Fluids
When a fluid is in constant acceleration, the pressure and buoyant force equations are modified. Suppose a beaker is placed in an elevator accelerating upward with a constant acceleration, a. In the beaker, assume there is a thin cylinder of height h with an infinitesimal cross-sectional area, ΔS.
The motion of the liquid within this infinitesimal cylinder is considered to obtain the pressure difference. Three vertical forces act on this liquid:
The motion of the liquid within this infinitesimal cylinder is considered to obtain the pressure difference. Three vertical forces act on this liquid:
Physiological Pharmacokinetic Models: Blood Flow-Limited Versus Diffusion-Limited Models
Physiological pharmacokinetic models, often called flow-limited or perfusion models, typically assume a swift drug distribution between tissue and venous blood, creating a rapid drug equilibrium. This premise is based on the idea that drug diffusion is extremely fast, and the cell membrane presents no barrier to drug permeation. In this scenario, where no drug binding occurs, the drug concentration in the tissue equals that of the venous blood leaving the tissue. This greatly simplifies the...
Newtonian Fluid: Problem Solving
Newtonian fluids exhibit a constant viscosity, meaning their shear stress and shear strain rate are directly proportional. This property ensures a predictable and stable response to applied forces, maintaining a linear relationship between force and flow. Examples include water, air, and light oils, consistently demonstrating this proportional behavior regardless of external conditions.
A velocity gradient forms within the fluid when a Newtonian fluid is placed between two parallel plates, with...
A velocity gradient forms within the fluid when a Newtonian fluid is placed between two parallel plates, with...
Navier–Stokes Equations
For incompressible Newtonian fluids, where density remains constant, stresses show a linear relationship with the deformation rate, defined by normal and shear stresses. Normal stresses depend on the pressure exerted on the fluid and the rate of deformation in specific directions, which determines how fluid flows under varying pressures. Shear stresses, on the other hand, act tangentially across fluid layers. They explain how adjacent fluid layers slide relative to one another, connecting...
Uniform Depth Channel Flow: Problem Solving
To calculate the flow rate for a trapezoidal channel, first, identify the bottom width, side slope, and flow depth of the channel. The cross-sectional area (A) corresponding to the depth of flow (y), channel bottom width (B), and side slope (θ) is determined by:Next, calculate the wetted perimeter, which includes the bottom width and the sloped side lengths in contact with the water. Using the values of the cross-sectional area and the wetted perimeter, determine the hydraulic radius by...
Applications of Integration to Find Blood Flow
Blood flow through a cylindrical blood vessel can be mathematically described using the principles of laminar flow, a regime in which fluid moves smoothly in parallel layers. In this model, the velocity of the blood is not uniform across the cross-section of the vessel; rather, it varies with the radial distance from the center. The maximum velocity occurs along the central axis, decreasing progressively toward the vessel walls, where it reaches zero due to viscous drag.Approximating Blood...


