Nessa Johnson, John Abraham^*, Zach Helgeson, Michael Hennessey

Frontiers in Heat and Mass Transfer, Vol.2, No.2, pp. 1-7, 2011, DOI:10.5098/hmt.v2.2.3006

Abstract A numerical simulation has been performed on the hemodynamics associated with embolization procedures. The flow geometry includes a multibranch artery which is upstream of a targeted tumor. During the procedure, drug-eluting particles are released into the local arterial geometry and are carried downstream by the flowing blood. The intention is to cause embolization of a daughter artery which feeds the tumor. As particles are injected into the blood stream, and as the embolization progresses, it is possible for the particulates to substantially alter the blood flow in the main artery. This alteration may lead to a maldistribution of blood flow… More >

Manimaran Renganathan, Thundil Karuppa Raj Rajagopal^*

Frontiers in Heat and Mass Transfer, Vol.4, No.1, pp. 1-11, 2013, DOI:10.5098/hmt.v4.1.3008

Abstract In this work, fuel spray parameters are studied by varying the fuel temperature. To overcome the tedious experimental task, a 3-D Computational Fluid Dynamics methodology is adopted by injecting fuel at specified temperatures of 313 K, 353 K and 393 K. The validation is accomplished after the optimal spatial and temporal steps of discretization are found out. At a fuel temperature of 313 K, advancing the injection timing from 6 deg bTDC to 20 deg bTDC increases cylinder peak pressure from 79.8 bar to 90.9 bar. Relation between the emission characteristics and spray SMD and temperature is studied. More >

Heather Dillon^a , Ashley Emery^b,† , Ann Mescher^b

Frontiers in Heat and Mass Transfer, Vol.4, No.2, pp. 1-9, 2013, DOI:10.5098/hmt.v4.2.3004

Abstract A computational model is presented that extends prior work on unsteady natural convection in a tall rectangular cavity with aspect ratio 10 and applies Proper Orthogonal Decomposition to the results. The solution to the weakly compressible Navier-Stokes equation is computed for a range of Rayleigh numbers between 2 × 10⁷ and 2.2 × 10⁸ with Prandtl number 0.71. A detailed spectral analysis shows dynamic system behavior beyond the Hopf bifurcation that was not previously observed. The wider Rayleigh range reveals new dynamic system behavior for the rectangular geometry, specifically a return to a stable oscillatory behavior that was not predicted… More >

Renganathan Manimaran^a, Rajagopal Thundil Karuppa Raj^b,*

Frontiers in Heat and Mass Transfer, Vol.5, pp. 1-9, 2014, DOI:10.5098/hmt.5.2

Abstract Diesel engine combustion modeling presents a challenging task with the formation and breakup of spray into droplets. In this work, 3D-CFD computations are performed to understand the behaviour of spray droplet diameter and temperature during the combustion by varying the swirl ratio and injection timing. After the validation and grid and time independency tests, it is found that increase in swirl ratio from 1.4 to 4.1 results in peak pressure rise of 8 bar and an advancement of injection timing from 6 deg bTDC to 20 deg bTDC results in increase of peak pressure by 15 %. More >

Ankit Kanor, R Manimaran^*

Frontiers in Heat and Mass Transfer, Vol.7, pp. 1-5, 2016, DOI:10.5098/hmt.7.25

Abstract One of the effective liquid cooling techniques for microelectronic devices is attaching micro channel heat sink to the inactive side of chip. A micro channel heat sink is a device that decreases temperature by flowing coolant through micro channels. The present study focuses on the conjugate heat transfer analyses for different cross-sections (trapezoidal, hexagonal, octagonal and circular).After present study is validated with the published result in the literature, the comparative study of parallel and counter flow configuration is performed. Different geometries are modeled using CATIA V5 software and simulated in ANSYS Fluent R14. From these CFD simulations, preferred configuration of… More >

Lili Lei^*, Ze Li, Haichao Zhou, Jing Wang, Wei Lin

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.1, pp. 147-163, 2024, DOI:10.32604/fdmp.2023.030158

Abstract The vehicle industry is always in search of breakthrough energy-saving and emission-reduction technologies. In recent years, vehicle intelligence has progressed considerably, and researchers are currently trying to take advantage of these developments. Here we consider the case of many vehicles forming a queue, i.e., vehicles traveling at a predetermined speed and distance apart. While the majority of existing studies on this subject have focused on the influence of the longitudinal vehicle spacing, vehicle speed, and the number of vehicles on aerodynamic drag and fuel economy, this study considers the lateral offset distance of the vehicle queue. The group fuel consumption… More >

Shiyang Song^1,*, Tongxin Han²

FDMP-Fluid Dynamics & Materials Processing, Vol.20, No.1, pp. 127-145, 2024, DOI:10.32604/fdmp.2023.030137

Abstract Aiming to mitigate the aerodynamic lift force imbalance between pantograph strips, which exacerbates wear and affects the current collection performance of the pantograph-catenary system, a study has been conducted to support the beam deflector optimization using a combination of experimental measurements and computational fluid dynamics (CFD) simulations. The results demonstrate that the size, position, and installation orientation of the wind deflectors significantly influence the amount of force compensation. They also indicate that the front strip deflectors should be installed downwards and the rear strip deflectors upwards, thereby forming a “π” shape. Moreover, the lift force compensation provided by the wind… More >

Shiyue Zhang¹, Xue Song^1,2, Jingying Wang^1,*, Wen Huang^3,*, Yue Zhou⁴, Mingrui Li¹

Molecular & Cellular Biomechanics, Vol.20, No.2, pp. 81-94, 2023, DOI:10.32604/mcb.2023.044445

Abstract Pulmonary embolism (PE), caused by deep venous thrombosis (DVT), is a disease with high morbidity and mortality. Implantation of inferior vena cava filters is an important method for the clinical prevention of PE. The hemodynamic characteristics of filters implanted in the inferior vena cava (IVC) have a significant impact on their performance. However, IVC diameters vary among patients. This may have a direct impact on the hemodynamic properties of the filter. At present, there is no research on this kind of problem to be investigated. In this paper, the hemodynamic properties of the VenaTech convertible filter were simulated in three… More > Graphic Abstract

Peishuo Wu¹, Chi Zhu^1,2,*

The International Conference on Computational & Experimental Engineering and Sciences, Vol.25, No.1, pp. 1-2, 2023, DOI: 10.32604/icces.2023.09869

Abstract Central blood pressure, i.e., the blood pressure near the heart, is an important physiological indicator of the cardiovascular function of a patient. However, direct measurement of this quantity is rarely carried out due to the invasive nature of the procedure. Instead, blood pressure at the arm (brachial artery) measured through an inflatable cuff is commonly used to represent or estimate the central blood pressure. On the other hand, the aortic pressure propagates downstream in the form of pulse waves, which have to pass through a complex and compliant vascular network to reach the brachial artery. Therefore, the efficacy of cuff-measured… More >

Junjie Chen^* , Wenya Song, Deguang Xu

Frontiers in Heat and Mass Transfer, Vol.8, pp. 1-10, 2017, DOI:10.5098/hmt.8.21

Abstract The combustion and heat transfer characteristics of hydrogen-air or methane-air mixtures in catalytic micro-combustors were studied numerically to assess the impact of wall thermal properties and key operation parameters on the thermal uniformity. A two-dimensional computational fluid dynamics (CFD) model was developed with detailed hetero-/homogeneous chemistry, heat conduction within the solid wall, surface radiation heat transfer, and external heat losses. Parametric studies were carried out to investigate the effect of wall thermal conductivity, feed composition, and flow rate on the thermal uniformity during highly exothermic catalytic reactions. Comparisons of hydrogen- with methane-air systems were made. Based on these insights, an… More >