Dong Hu^1,2, Lingxing Hu³, Facheng Qiu^3,*

Frontiers in Heat and Mass Transfer, Vol.23, No.6, pp. 1865-1882, 2025, DOI:10.32604/fhmt.2025.073409 - 31 December 2025

Abstract With the acceleration of industrialization and urbanization, ammonia nitrogen pollution in water bodies has become increasingly severe, making the development of efficient and low-consumption wastewater treatment technologies highly significant. This study employs three-dimensional computational fluid dynamics (CFD) to investigate the cavitation mechanisms and flow field characteristics in a novel jet impingement-negative pressure ammonia removal reactor. The simulation, validated by experimental pressure data with a high degree of consistency, utilizes the Mixture model, the Realizable k-ε turbulence model, and the Schnerr-Sauer cavitation model. The results demonstrate that the flow velocity undergoes a substantial acceleration within the… More > Graphic Abstract

Sudipta Debnath¹, Zahir Uddin Ahmed², Muhammad Ikhlaq^3,4,*, Md. Tanvir Khan⁵, Avneet Kaur⁶, Kuljeet Singh Grewal¹

Frontiers in Heat and Mass Transfer, Vol.23, No.1, pp. 71-94, 2025, DOI:10.32604/fhmt.2024.059734 - 26 February 2025

Abstract Impinging jet arrays are extensively used in numerous industrial operations, including the cooling of electronics, turbine blades, and other high-heat flux systems because of their superior heat transfer capabilities. Optimizing the design and operating parameters of such systems is essential to enhance cooling efficiency and achieve uniform pressure distribution, which can lead to improved system performance and energy savings. This paper presents two multi-objective optimization methodologies for a turbulent air jet impingement cooling system. The governing equations are resolved employing the commercial computational fluid dynamics (CFD) software ANSYS Fluent v17. The study focuses on four… More > Graphic Abstract

Ali Chitsazan^a , Georg Klepp^a, Mohammad Esmaeil Chitsazan^b, Birgit Glasmacher^c

Frontiers in Heat and Mass Transfer, Vol.18, pp. 1-6, 2022, DOI:10.5098/hmt.18.17

Abstract For the optimization of the impinging round jet, the pressure force coefficient and drying energy consumption on the moving curved surface are set as the objective functions to be minimized simultaneously. SHERPA search algorithm is used to search for the optimal point from multiple objective tradeoff study (Pareto Front) method. It is found that the pressure force coefficient on the impingement surface is highly dependent on the jet to surface distance and jet angle, while the drying energy consumption is highly dependent on the jet to jet spacing. Generally, the best design study during the More >

Ali Chitsazan^a, Georg Klepp^a, Birgit Glasmacher^b

Frontiers in Heat and Mass Transfer, Vol.18, pp. 1-9, 2022, DOI:10.5098/hmt.18.16

Abstract The effect of jet Reynolds number, jet exit angle, the nozzle to surface distance, jet to jet spacing on the heat transfer, and pressure force performance from multiple impinging round jets on a moving curved surface have been numerically evaluated. Two correlations are developed and validated for the average Nu number and the pressure force coefficient and the agreement between the CFD and correlations was reasonable. The surface motion effect becomes more pronounced on the Nu number distribution for low jet Re number, high jet to jet spacing, large jet to surface distance, and angled More >

Ali Chitsazan^a , Georg Klepp^a, Birgit Glasmacher^b

Frontiers in Heat and Mass Transfer, Vol.18, pp. 1-7, 2022, DOI:10.5098/hmt.18.15

Abstract The effect of surface curvature, number of jets, number of jet rows, jet arrangement, crossflow, and surface motion on the heat transfer and pressure force performance from multiple impinging round jets on the moving flat and curved surface have been numerically evaluated. The more number of jets (more than three jets) has no significant effect on the average heat transfer rate. The more number of jet rows increases the strength of wall jets interference and crossflow effects and degrade the average heat transfer rates. There is a minor difference between inline and staggered arrangements on More >

Ali Chitsazan^a,*, Georg Klepp^a, Birgit Glasmacher^b

Frontiers in Heat and Mass Transfer, Vol.19, pp. 1-8, 2022, DOI:10.5098/hmt.19.35

Abstract The objective of the present research is the prediction of large arrays of impingement jets using a computational model. The heat transfer and the force coefficient from single and multiple jet rows (1, 2, 4, 8, and infinity rows) for two different nozzle shapes as either orifice or straight pipe on a fixed flat surface were numerically investigated for drying applications to understand the physical mechanisms which affect the uniformity of the local heat transfer and pressure force coefficient as well as average heat transfer coefficient. The pipe has always a higher averaged Nu and More >

Taidong Xu^1,2, Hao Liu², Dejun Zhang^1,2, Yadong Li², Xiaoming Zhou^2,*

FDMP-Fluid Dynamics & Materials Processing, Vol.17, No.1, pp. 109-121, 2021, DOI:10.32604/fdmp.2021.010608 - 09 February 2021

Abstract With the progressive increase in the number of transistors that can be accommodated on a single integrated circuit, new strategies are needed to extract heat from these devices in an efficient way. In this regard methods based on the combination of the so-called “jet impingement” and “micro-channel” approaches seem extremely promising for possible improvement and future applications in electronics as well as the aerospace and biomedical fields. In this paper, a hybrid heat sink based on these two technologies is analysed in the frame of an integrated model. Dedicated CFD simulation of the coupled flow/temperature More >

Naveen G. Patil, Tapano Kumar Hotta^*

Frontiers in Heat and Mass Transfer, Vol.11, pp. 1-13, 2018, DOI:10.5098/hmt.11.16

Abstract The manuscript deals with the critical review for cooling of discrete heated electronic components using liquid jet impingement. Cooling of electronic components has been a lead area of research in recent years. Due to the rapid growth of electronic industries, there is an enormous rise in the system power consumption, and the reduction in the size of electronic components has led to a rapid increase in the heat dissipation rate per unit volume of components. The present paper deals with the role of liquid jet impingement (heat flux removal rate 200 - 600 W/cm²) for cooling… More >

A. Balabel^1,2,3, W. A. El-askary², S. Wilson²

CMES-Computer Modeling in Engineering & Sciences, Vol.95, No.6, pp. 483-499, 2013, DOI:10.3970/cmes.2013.095.483

Abstract In the present paper, the impingement of air jet on a heated flat plate subjected to a periodic oscillation is numerically and experimentally investigated. The motivation of the present research is the desire to enhance the heat transfer characteristics during the cooling process of a heated flat plate which can be found in many relevance industrial applications. In order to improve the heat transfer characteristics, a novel idea is utilized, where a periodical oscillation movement in form of sine wave produced from a Scotch yoke mechanism is applied to the heated flat plate. The obtained More >

Emad Elnajjar¹, Mohammad O. Hamdan, Yousef Haik

FDMP-Fluid Dynamics & Materials Processing, Vol.9, No.1, pp. 77-89, 2013, DOI:10.3970/fdmp.2013.009.077

Abstract In this paper, two heat transfer configurations (central-jet and side-jet) of jet impinging on a semicircular surface are experimentally studied. The internal channel is formed using flat insulated wall and a semi-circular surface using a curved flexible heater with a uniform heat flux. A set of experiments have been performed for the purpose of assessing the heat augmentation and pressure drop between the two jet configurations. The measurements include the inlet and outlet flow temperatures using thermocouples, the temperature map of the flexible heater using thermal infra-red camera, the flow rates using rotary meter and More >