RESEARCH PROJECTS

Cardiovascular Fluid Dynamics

Blood flow in the human cardiovascular system is highly complex. Abnormal hemodynamics is linked to severe diseases and has driven decades of fluid dynamics research. Yet, the transient nature of flow and fluid–structure interactions leave many aspects of aortic hemodynamics poorly understood. 

Quantitative experimental measurements can advance our understanding of cardiac pathologies, support improved medical device design, and provide validation benchmarks for patient-specific simulations.

Related publications:

• A B M Nazmus Salehin Nahid, Mashrur Muntasir Nuhash, Ruihang Zhang. (2025). Hemodynamics Implications of Aortic Stenosis on Ascending Aortic Aneurysm Progressive: A Patient-Specific CFD Study. Submitted to Journal of Vascular Diseases on 08/21/2025.

• Mashrur Muntasir Nuhash, Victor K. Lai, Ruihang Zhang. (2025). Hemodynamic Alteration in Aortic Valve Stenosis: CFD Insights from Leaflet-Resolved Models. Bioengineering 2025,12(10),1029. https://doi.org/10.3390/bioengineering12101029.

• Zhang, Y., Zhang, R., Thomas, N., Ullah, Al., Eichholz, B., Estevadeordal, J., & Suzen, Y. (2022). Experimental and Computational Study of Pulsatile Flow Characteristics in Romanesque and Gothic Aortic Arch Models. Medical Engineering & Physics, 102: 103784. https://doi.org/10.1016/j.medengphy.2022.103784. 

• Zhang, R., & Zhang, Y. (2020). Effects of heart rate on the pulsatile flow characteristics of a stenotic aortic valve model: an in vitro experimental study. ASME. Journal of Fluids Engineering, 142(10): 101205. https://doi.org/10.1115/1.4047410.

Cerebrovascular Fluid Dynamics - Brain aneurysm

Cerebrovascular fluid dynamics study how blood flows within the brain's arteries to understand the initiation, growth, and rupture of cerebral aneurysms. Both Computational Fluid Dynamics (CFD) and experimental methods - PIV technique can be employed to analyze wall shear stress (WSS) and flow patterns, revealing that abnormal hemodynamics, such as low WSS in some areas and high WSS in others, can damage the artery wall and lead to aneurysm formation and growth. 

Related publications:

• Chowdhury, P., Lai, Victor., & Zhang, R. (2025). Fluid Dynamics of Brain Aneurysms: A Review of Computational and experimental Studies. Biomechanics 2025,5(2), 36. https://doi.org/10.3390/biomechanics5020036.

Additive Manufacturing - 3D Printing

3D printing is largely interchangeable terms for a process that builds a 3D object layer by layer from a digital design, rather than removing material. The processes rely on computer-aided design (CAD) data and various materials like plastics, metals, and ceramics to create objects, enabling complex geometries and new design possibilities not possible with traditional methods.

Our lab offers both the traditional FDM and Resin 3D printing to fabricate project-specific models for potential use in PIV experiments.

• Benjamin Eichholz (2019 - 2020) Mechanical Engineering, North Dakota State University

Lab Experiment: Fundamental mechanisms of pulsatile flow over cavities with superhydrophobic coatings with applications in cardiovascular devices.

Designed and installed lab PIV setup with Ben, helped him in coding and data analysis, mentored him throughout the experiments.

• Senior Design group, Mechanical Engineering Department, North Dakota State University, Spring 2018

     Group member: Clarie DeJong, Alec Halvorson, Mitchell Munar, Jonas Sahouani, Christorpher Wreede

    Topic: Artificial aortic valve based on silk fibroin

Helped with test the flow characteristics of artifical aortic valve model.

• Garrett Naughton (2016 - 2017) & Louis Miller (2017 - 2018) Mechanical Engineering, North Dakota State University

Worked with Garrett and Louis to design, construct and remodel the PIV assisted circulatory mock flow simulator

• Senior Design group, MIE Department, University of Minnesota - Duluth (Fall 2022)

    Group member: Noah Klatt, Connor Nadeau, Paul Foldesi

    Topic: Design of the closed-loop cardiovascular apparatus (CLCA)

• Undergraduate Research Opportunities Program (UROP), MIE Department, University of Minnesota - Duluth (Spring 2024) 

    Group member: Seonggwang (Jayden) Ryu

    Topic: Fabrication of aortic valve models via 3D Printing

• Senior Design group, MIE Department, University of Minnesota - Duluth (Spring 2024)

    Group member: Travis Voigt, Patrick Kult, Morgan Boros

    Topic: Analysis of Stenosis Impact on the Hemodynamics Surrounding the Aortic Heart Valve -CFD  Simulation and Testing Apparatus Design

• Senior Design group, MIE Department, University of Minnesota - Duluth (Spring 2025)

     Group member: Seonggwang (Jayden) Ryu, Benjamin Bauer, Tristan Anderson

   Topic: Fabrication and Preliminary CFD Simulation of Cerebral (Brain) Aneurysm