Special Issue "Recent Advances in Fluid Mechanics and Thermal Sciences"

Submission Deadline: 31 December 2021 (closed)
Guest Editors
Dr. Jingying Wang, Shandong University, wjy_sdu@sdu.edu.cn


The independent or coupled processes of fluid flow and heat transfer commonly occur in many science and engineering problems, such as blood circulation, weather forecast, combustion, material processing, heat exchanger and aerodynamic heating, etc. This special issue aims to highlight recent advances in fluid mechanics and thermal sciences (RAFT), and theoretical, numerical and experimental research on any science and engineering problems are all welcome. Original and review articles on RAFT are both encouraged, including but not limited to the following potential topics: 

• Hydrodynamics and Aerodynamics

• Energy and Power Engineering

• Marine Engineering

• Building Environment

• Pollution Control

• Chemistry and Chemical Engineering

• Biofluid and Bioheat

• Advanced Manufacture

Hydrodynamics, Aerodynamics, Thermal Engineering, Marine Engineering, Building Environment, Pollution Control, Chemical Engineering, Biofluid, Advanced Manufacture

Published Papers

  • Numerical Application of the Flamelet Model to Supersonic Turbulent Combustion
  • Abstract In this study, the flow field structure inside a scramjet combustor is numerically simulated using the flamelet/progress variable model. Slope injection is considered, with fuel mixing enhanced by means of a streamwise vortex. The flow field structure and combustion characteristics are analyzed under different conditions. Attention is also paid to the identification of the mechanisms that keep combustion stable and support enhanced mixing. The overall performances of the combustion chamber are discussed. More
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  • Performance Analysis of an Organic Rankine Cycle with a Preheated Ejector
  • Abstract The so-called organic Rankine cycle (ORC) is an effective technology allowing heat recovery from lower temperature sources. In the present study, to improve its thermal efficiency, a preheated ejector using exhaust steam coming from the expander is integrated in the cycle (EPORC). Considering net power output, pump power, and thermal efficiency, the proposed system is compared with the basic ORC. The influence of the ejector ratio (ER) of the preheated ejector on the system performances is also investigated. Results show that the net power output of the EPORC is higher than that of the basic ORC due to the decreasing… More
  •   Views:400       Downloads:414        Download PDF

  • Experimental Analysis of the Influence of Exhaust Thermal Management on Engine NOx Emission
  • Abstract Exhaust thermal management is essential to allow engines to meet the Euro VI emissions standards and reducing nitrogen oxide emissions is one of the most important targets being pursued nowadays. Along these lines, in the present study, engine’s thermal performances have been evaluated on the basis of a WHTC test, namely a transient engine dynamometer schedule defined by the global technical regulation (GTR) developed by the UN ECE GRPE group (the GTR is covering a world-wide harmonized heavy-duty certification (WHDC) procedure for engine exhaust emissions). The influence of thermal management on fuel consumption, intake, and tailpipe NOx have been quantitatively… More
  •   Views:1108       Downloads:450        Download PDF

  • Numerical Investigation into the Transient Behavior of the Spike-Type Rotating Stall for a Transonic Compressor Rotor
  • Abstract In this paper, a numerical investigation into a spike-type rotating stall process is carried out considering a transonic compressor rotor (the NASA Rotor 37). Through solution of the Unsteady Reynolds-Averaged Navier-Stokes (URANS) equations, the evolution process from an initially circumferentially-symmetric near-stall flow field to a stable stall condition is simulated without adding any artificial disturbance. At the near-stall operating point, periodic fluctuations are present in the overall flow of the rotor. Moreover, the blockage region in the channel periodically shifts from middle span to the tip. This fluctuating condition does not directly lead to stall, while the full-annulus calculation eventually… More
  •   Views:446       Downloads:386        Download PDF

  • CFD Analysis and Optimization of a Diesel Engine Cooling Water Jacket
  • Abstract The STAR-CCM + software is used to investigate the flow inside a cooling water jacket of an in-line six-cylinder diesel engine. The results show that the average flow velocity of the cooling water inside the jacket is 1.669 m/s while the flow velocity distribution is not uniform for each cylinder. Moreover, the fluid velocity in proximity to the cylinder head is too low, thereby affecting the cooling performances of the water jacket. Two corresponding structural optimization schemes are proposed to mitigate this issue and the post-optimization performances of the water jacket are discussed in detail. More
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  • An Experimental Study on the Void Fraction for Gas-Liquid Two-Phase Flows in a Horizontal Pipe
  • Abstract The flow patterns and the void fraction related to a gas-liquid two-phase flow in a small channel are experimentally studied. The test channel is a transparent quartz glass circular channel with an inner diameter of 6.68 mm. The working fluids are air and water and their superficial velocities range from 0.014 to 8.127 m/s and from 0.0238 to 0.556 m/s, respectively. The void fraction is determined using the flow pattern images captured by a high-speed camera, while quick closing valves are used for verification. Four flow patterns are analyzed in experiments: slug flow, bubbly flow, annular flow and stratified flow.… More
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  • Assessment of the Application of Subcooled Fluid Boiling to Diesel Engines for Heat Transfer Enhancement
  • Abstract The increasing demand of cooling in internal combustion engines (ICE) due to engine downsizing may require a shift in the heat removal method from the traditional single phase liquid convection to the application of new technologies based on subcooled fluid boiling. Accordingly, in the present study, experiments based on subcooled flow boiling of 50/50 by volume mixture of ethylene glycol and water coolant (EG/W) in a rectangular channel heated by a cast iron block are presented. Different degrees of subcooling, velocity and pressure conditions are examined. Comparison of three empirical reference models shows that noticeable deviations occur especially when low… More
  •   Views:789       Downloads:634        Download PDF

  • Investigation on the Changing Characteristics of Flow-Induced Noise in a Centrifugal Pump
  • Abstract Centrifugal pumps are widely used in engineering for a variety of applications. A known drawback of these devices is the high-level noise generated during operations, which can affect their stability and adversely influence the entire working environment. By combining the Powell vortex sound theory, numerical simulations and experimental measurements, this research explores the trends of variation and the corresponding underlying mechanisms for the flow-induced noise at various locations and under different operating conditions. It is shown that the total sound source intensity (TSSI) and total sound pressure level (TSPL) in the impeller, in the region between the inlet to the… More
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  • Thermal Analysis of a Novel Oil Cooled Piston Using a Fluid-Solid Interaction Method
  • Abstract Thermal load has a vital influence on the normal operation and service life of diesel engines. In this study, the thermal load and oil-cooling effect on diesel engine pistons were investigated by means of computational fluid dynamics. In particular, the flow and heat transfer characteristics of the cooling gallery were determined during the oscillation of the piston. Moreover, the temperature field distribution of the piston with and without the cooling gallery were compared. The results revealed that the cooling gallery has a prominent effect on reducing the thermal load on the piston crown and piston lands. To fully understand the… More
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  • Thermo-Mechanical Analysis of the Sealing Performance of a Diesel-Engine Cylinder Gasket
  • Abstract Taking the combustor composite structure of a high-strength diesel engine as the main research object, dedicated tests have been conducted to verify the accuracy of three distinct cylinder gasket pressure simulation models. Using the measured cylinder gasket compression rebound curve, a gasket unit has been designed and manufactured. For this unit, the influence of the bolt pretension, cylinder body and cylinder head material on gasket sealing pressure has been investigated systematically in conditions of thermo-mechanical coupling. The results show that the bolt pretension force is one of the most important factors affecting the cylinder gasket sealing pressure. The change of… More
  •   Views:911       Downloads:1109        Download PDF

  • Analysis of Bubble Behavior in a Horizontal Rectangular Channel under Subcooled Flow Boiling Conditions
  • Abstract Experiments on subcooled flow boiling have been conducted using water in a rectangular flow channel. Similar to the coolant channel in internal combustion engines (IC engines), the flow channel in this experiment was asymmetrically heated. Bubble images were captured using a high speed camera from the side view of the channel. The experimental conditions in terms of bulk temperature, bulk velocity, pressure and heat flux ranged from 65°C–75°C, 0.25 m/s–0.75 m/s, 1–1.7 bar and 490 kW/m2–700 kW/m2, respectively. On the basis of these tests, a statistical analysis of the bubble size has been conducted considering a population of 1400 samples.… More
  •   Views:1397       Downloads:1241        Download PDF