CFD

Since the introduction of the digital computer in the 1950s, computational fluid dynamics (CFD) has increasingly been used to study and solve complex problems in fluid flow and heat transfer. With the rising popularity of sophisticated computing tools, many challenging engineering problems tend to be assigned to the CFD simulation world...
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Header flow maldistribution and pressure loss in air-cooled heat exchangers may significantly affect performance. Most relevant literature focuses on plate-fin and cylindrical channel headers for tubular heat exchangers. The flow in the header is affected by its internal geometry, the orientation of the nozzles on the header, and inlet flow velocity....
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This webinar will discuss Xist and CFD predictions of three NTIW exchanger configurations – 2 baffle, 4 baffles, and 6 baffles. The discussion will focus on the contributions of crossflow and longitudinal flow on heat transfer, which is due to varied baffle spacing for the same baffle cut. During the webinar,...
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Compact plate-fin heat exchangers are widely used for electronics, aerospace, and automotive cooling because of the light weight and small size. The majority of open-literature data use air as the test fluid; thus, the application of the ensuing air-based methods to higher Prandtl number, liquid services is dubious. In some applications,...
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API-compliant air coolers are modeled in two- and three-dimensional computational fluid dynamics (CFD) simulations to see what improvements are needed in Xace with regard to the airside maldistribution. We validated the CFD model using Xace base cases. We then used CFD to simulate non-ideal airside flow situations that can potentially affect...
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HTRI currently runs fouling experiments on the High Temperature Fouling Unit (HTFU) which recirculates a 27 liter sample of crude for periods up to one month. As we plan to expand our crude oil fouling test program, we are investigating alternate test methods to screen crude oil fouling with smaller sample...
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Xist can predict unexpected performances of shellside viscous fluids in laminar regimes, where thermal maldistribution is present. The heat transfer of viscous flows across vertical baffles is analyzed by CFD to determine impact of such non-uniformity. Maldistribution can be monitored using a viscosity-independent Richardson number. The Richardson relates the impact of...
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During this webinar, we discuss the basics of sealing devices, including common practices and design guidelines. Further, we review the basic flow resistance equation for sealing strips used in Xist Version 7 and compare the measured performances of HTRI research-scale heat exchanger using sealing strips to CFD and Xist predictions....
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Over the past several decades, the accuracy and usability of computational methods have substantially improved. This report reviews the complicated physics of two-phase flow and phase change, presents the equations of motion for a two-phase flow with various closure models, and compares current computational approaches. Although inadequate for the entire spectrum of...
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We completed a multiphysics computational simulation of a shell-and-tube exchanger, where simultaneous fluid flow and heat transfer of both fluid streams occurred. Temperature-induced mechanical stress also acted on the solid structures. A weak coupling of a finite-volume CFD Navier-Stokes model with a finite-element computational solid mechanics model underlies the multiphysics simulation....
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HTRI experimentally evaluated the thermal-hydraulic performance of a water-water plate-and-shell heat exchanger at the Research & Technology Center and then used the results to calibrate a solution approach through computational fluid dynamics. The tortuous flow paths through the corrugated channels of the plate pack were modeled effectively using porous media. Inertial resistance...
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