Bassam Ali Jubran

Toronto Metropolitan University (formerly Ryerson University)

The present study numerically evaluates the influence of hole inclination angle with a hole imperfection on film cooling performance. Here, the hole imperfection due to laser percussion drilling is modelled as a half torus. Three hole inclination angles were investigated: 35°, 45° and 55°. Furthermore, every case was evaluated at three blowing rati...

This study introduces a novel and simple strategy; compound angle upstream sister holes (CAUSH) to increase film cooling performance of the cylindrical hole by combining two techniques: Sister holes; (two small round holes placed upstream the primary hole) and compound angle hole. Whereas the upstream sister holes were injected at several compound...

This paper presents a numerical investigation of film cooling performance and the flow field of a single micro cooling hole with 200 µm diameter on a flat plate at four blowing ratios; M=0.25, 0.5, 1.0, and 1.5. The computation was performed using FLUENT-ANSYS by solving the 3D Reynolds Averaged Navier-Stokes Equations. The Realizable k-ε was chose...

This study is a parametric numerical analysis of film cooling performance for a short cooling hole with the effect of cooling hole angle of injection, hole shape, as well as the blowing rate. The simulation was performed on Fluent Ansys using the k- ɛ turbulence model with various wall functions. The numerical results validated with the experimenta...

h i g h l i g h t s Variation of sister holes location for film cooling is numerically investigated. Streamwise variations have insignificant effect on film cooling effectiveness. Spanwise variations have significant effect on film cooling effectiveness. Farther spanwise locations increases the lateral spread of the coolant. a b s t r a c t In the...

In the present paper, a numerical investigation is conducted on film cooling performance from novel sister-shaped single-hole schemes. Based on the sister hole film cooling technique, shaped holes are formed by merging discrete sister holes to a primary hole. Simulations are performed at four blowing ratios of 0.25, 0.5, 1, and 1.5. The novel-shape...

In the present study, a numerical evaluation of the performance of the sister-shaped single-hole (SSSH) schemes (downstream, upstream and up/downstream) on the leading edge of AGTB-B1 high pressure turbine blade cascade is carried out. Simulations are performed at three blowing ratios of 0.7, 1.1 and 1.5. Predicted results are compared to the singl...

The film cooling effectiveness and the jet exit conditions as well as the associated vortex structure downstream of the injection hole for both a circular exit shaped hole and an elliptical exit shaped holes were numerically investigated for the blowing ratios of 0.25, 0.5, 1 and 1.5. Four turbulence models including the standard, RNG, realizable k...

The performance of the coolant for film cooling from micro-hole was numerically computed over a flat plate and compared with the performance of the coolant from macro-hole. The comparison between the prediction of two equation standard and realizable k-ε turbulence models with two-layer near wall treatment was used to validate the suitability of th...

The film cooling performance using novel sister shaped single-hole (SSSH) schemes are numerically investigated in the present study. The downstream, upstream and up/downstream SSSH configurations are formed by merging the discrete sister holes to the primary injection hole through a series of specific orientations. The obtained results are compared...

A numerical study on the effects of sister holes locations on film cooling performance is presented. This includes the change of the location of the individual discrete sister holes in the streamwise and spanwise directions, where each one of these directions includes 9 different locations, The simulations are performed using three-dimensional Reyn...

A numerical investigation of the film cooling performance from novel sister shaped single-holes (SSSH) is presented in this paper and the obtained results are compared with a single cylindrical hole, a forward diffused shaped hole, as well as discrete sister holes. Three types of the novel sister shaped single-hole schemes namely downstream, upstre...

In traditional film cooling configuration, coolant is injected through a cylindrical pipe with an inclined angle (0<a<90), which results in an elliptical exit shaped hole (EESH) at the blade surface. The present study makes use of an elliptical injection coolant pipe that leads to a circular exit shaped hole (CESH). The film cooling effectiveness a...

This paper reports a computational analysis on the effect of sister hole control on film cooling from short holes. The proposed method includes surrounding a primary injection hole by two or four smaller sister holes to actively maintain flow adhesion along the surface of the blade. A numerical study using the realizable k-ε turbulence model led to...

This paper reports a computational investigation on the effects of mainstream turbulence intensity on film cooling effectiveness from trenched holes over a symmetrical blade. Computational solutions of the steady, Reynolds-Averaged Navier-Stokes equations are obtained using a finite volume method with k - epsilon Turbulence model. Whenever possible...

This paper reports a numerical investigation on the prediction of the thermal and hydrodynamic flow fields of multi micro jet impingement cooling of three dimensional turbine vanes. A three dimensional vane is modeled with an in-line array of impinging jets of diameters 0.5 and 0.25 mm. The numerical model consists of the steady, Reynolds-Averaged...

The purpose of this numerical investigation is to study the micro-jet impingement heat transfer characteristics and hydromechanics in a 3-D, actual-shaped turbine vane geometry. No concession is made on either the skewness or curvature profile of the airfoil in the streamwise direction, nor to the lean, airfoil twist or tapering of the vane in the...

Purpose The purpose of this paper is to report a numerical investigation of jet‐cross‐flow interaction in the presence of imperfection inside the injection hole with application to film cooling of turbine blades. Design/methodology/approach The work includes the prediction of the thermal and hydrodynamic fields by solving the Reynolds Averaged Nav...

The influence of various incidence angles on film cooling effectiveness of an axial turbine blade cascade with leading edge ejection from two rows of cooling holes is numerically investigated. The rows are located in the vicinity of the stagnation line. One row is located on the suction side and the other one is on the pressure side. The predicted...

Computational results are presented for a row of coolant injection holes on each side of a high-pressure turbine blade near the leading edge. Seven hole configurations have been used to show the effect of various diffusion shaped holes and their trenching on film cooling effectiveness: (1) cylindrical film hole; (2) forward diffused film hole; (3)...

This paper presents an investigation on the effect of sister holes on film cooling. The proposed technique surrounds a primary injection hole by two or four smaller sister holes to actively maintain flow adhesion along the surface of the blade. A numerical evaluation using the realizable k-ε turbulence model led to the determination that the use of...

This paper presents an investigation on the effect of sister holes on film cooling. The proposed technique surrounds a primary injection hole by two or four smaller sister holes to actively maintain flow adhesion along the surface of the blade. A numerical evaluation using the realizable k-e turbulence model led to the determination that the use of...

A simplified impingement high pressure turbine vane is modeled and solved via Fluent. A relatively flat section of the vane is fitted with 15 0.51mm diameter impingement holes - 5 rows of 3 jets. Results are then compared to known experimental data. Two different turbulence models are used to study this preliminary configuration: K-omega SST and th...

A numerical study was performed to evaluate the effectiveness of the novel sister hole film cooling technique. Two secondary coolant holes bound the primary coolant hole slightly downstream of its midpoint, intended to minimize the primary vortex pair and improve cooling performance. An unstructured hexahedral mesh was generated and the realizable...

La présente étude concerne un cas d’interaction entre un jet se développant perpendiculairement à un écoulement transversal. L’application directe d’une telle configuration se trouve principalement dans les systèmes de refroidissement par film appliqués aux aubes des turbines à gaz. En premier lieu une validation du modèle mathématique est effectué...

The present study evaluates a novel sister hole cooling technique using large inclination angle cylindrical holes simulated numerically. Here, a 55 inclination angle has been applied to simulate more realistic turbine conditions. Two sister holes bound the primary injection hole and are shifted slightly downstream to promote flow adhesion. As a mea...

The focus of this comparative-numerical study is to investigate the effects of advanced cooling hole geometries on film cooling effectiveness. Computational results are presented for a row of coolant injection holes on each side of an asymmetrical turbine blade model near the leading edge. Six film cooling configurations are considered in the prese...

Analysis of pressure transients in multiphase flow in a real flow line upstream of a manifold in an oil-gathering station in the presence of slug flow is presented. The transient analysis is based on the solution of the partial differential equations governing the pressure transients using the method of characteristics. The analysis permitted the i...

Jet impingement cooling remains one of the key methods in various high-end cooling applications as it can induce higher heat transfer rates. The objective of this preliminary investigation is to shed some light on micro-impingement cooling and assess the accuracy for a future 3-dimensional turbine blade model. For the purpose of this study, several...

Film cooling has been the primary focus of turbine blade cooling research for the past half century. However, as engines become more powerful, more effective non-traditional means of cooling become necessary. The current study branches out into a new scheme for film cooling; sister holes. The geometry of the current work makes use of three cylindri...

This paper presents a comparative-numerical investigation on film cooling from a row of simple and compound-angle holes injected at 35° on a flat plate with four film cooling configurations: (1) cylindrical film hole; (2) 15° forward diffused film hole; (3) trenched cylindrical film hole; (4) trenched 15° forward-diffused film hole. All simulations...

This paper reports a computational investigation on the effects of mainstream turbulence intensity on film cooling effectiveness from trenched holes over a symmetrical blade. Computational solutions of the steady, Reynolds-Averaged Navier-Stokes equations are obtained using a finite volume method with k – ε Turbulence model. Whenever possible, comp...

This paper investigates the performance of the SSG (Speziale, Sarkar, and Gatski) Reynolds Stress Model for the prediction of film cooling at the leading edge of a symmetrical turbine blade model using the CFX 5.7.1 package from ANSYS, Inc. Using a finite-volume method, the performance of the selected turbulence model is compared to that of the sta...

This paper presents a comparative-numerical investigation on film cooling from a row of simple and compound-angle holes injected at 35� on a flat plate with four film cooling configurations: (1) cylindrical film hole; (2) 15� forward diffused film hole; (3) trenched cylindrical film hole; (4) trenched 15� forward-diffused film hole. All simulations...

A micro heat exchanger (MHE) can effectively control the temperature of surfaces in high heat flux applications. In this study, several turbulence models are analyzed using a 3D finite element model of a MHE. The MHE consists of a narrow planar flow passage between flat parallel plates with small cylindrical pin fins spanning these walls. The pin f...

Computational results are presented for a row of coolant injection holes on each side of a symmetrical turbine blade model near the leading edge. Four film cooling configurations, (1) a cylindrical film hole, (2) a forward diffused film hole, (3) a cylindrical film hole within a transverse slot, and (4) a forward-diffused film hole within a transve...

There is a growing interest in design and manufacturing of micro-heat exchangers embedded in turbine blades of the jet engine for turbine blade cooling. The pertaining manufacturing technologies fall under micro-meso manufacturing, including subtractive methods, additive methods, and near net shaping methods. The purpose of this paper is to provide...

The performance of the SSG Reynolds Stress Model for the prediction of film cooling at the leading edge of a symmetrical turbine blade model is investigated. The test case blade model is symmetric and has one injection row of discrete cylindrical holes on each side near the leading edge. In the present computation several blowing ratios of 45° late...

The present investigation involves the prediction of film cooling from two rows of holes using different turbulence models. Predictions of film cooling effectiveness and the velocity field from two rows of holes inclined in the streamwise direction are presented using the k-ω model and a modified version of it, as well as the standard k-ε model tog...

This paper presents a numerical prediction of a new 3D film cooling hole geometry, the converging slot-hole or console. The console geometry is designed in order to improve the heat transfer and aerodynamic loss performance of turbine vane and rotor blade cooling systems without loosing the mechanical strength of a row of discrete holes. The cross...

The paper presents computations of a new film cooling geometry that is designed to offer an improved cooling of slot geometry, while retaining the mechanical strength of discrete holes. The exact experimental geometry of Sargison et al. (2002) is reproduced using the ANSYS CFX CFD software. For comparison purpose cylindrical holes are also consider...

Computational results are presented for a row of simple and compound-angle holes injected at 35 deg on a flat plate with four film cooling configurations: (1) cylindrical film hole; (2) 15 deg forward diffused film hole; (3) cylindrical film hole within transverse slot; (4) 15 deg forward-diffused film hole within transverse slot. All simulations a...

In this study the Typical Meteorological Year (TMY) data for the Seeb/Muscat area of the Sultanate of Oman is presented and analyzed. The analysis shows that diurnal variations in dry-bulb temperature are relatively small. However, seasonal variation indicates two distinct seasons: the hot season covering the months of April through to October (amb...

A Micro Heat Exchanger (MHE) can effectively control the temperature of surfaces in high heat flux applications. In this study, several turbulence models are analyzed using a 3-D finite element model of a MHE. The MHE consists of a narrow planar flow passage between flat parallel plates with small cylindrical pin fins spanning these walls. The pin...

This paper describes the results of an experimental study of drag reduction in a circulatory vertical pipe system for both upward and downward flows using a drag reduction agent, corrosion inhibitor, and a cheap detergent (washing-up liquid) with various concentrations for different flow rates.It was found that the corrosion inhibitor did not produ...

In this paper, recent work on drag reducing agents in single and multiphase flow pipelines is reviewed. Focus is placed on theories of drag reduction, the influence of drag reduction agent types, and hydrodynamic and heat transfer characteristics of flows in the presence of drag reducing additives. Questions are raised, shortcomings are assessed, a...

This paper involves the prediction of convective layers on the sidewalls of a solar pond. A three-dimensional finite-volume method for incompressible flows with different initial and boundary conditions is applied for the solution of convective layers generated on solar pond walls. A parametric study was conducted to predict the effects of wall til...

This paper describes the results of an experimental investigation into the effect of pressure gradient on the film cooling effectiveness from compound angle holes at both injection rows or the combination of one row of simple angle holes and one row of compound angle holes. Two pressure gradients were used in the range from −1.11 × 10−6 to +1.11 ×...

This paper reports the numerical modeling of turbulent flow and convective heat transfer over a wavy wall using a two equations eddy viscosity turbulence model. The wall boundary conditions were applied by using a new zonal modeling strategy based on DNS data and combining the standard k– turbulence model in the outer core flow with a one equation...

Typical film-cooling configuration of a symmetrical turbine blade leading edge is investigated using a three-dimensional finite volume method and a multi-block technique. The computational domain includes the curved blade surface as well as the coolant regions and the plenum. The turbulence is approximated by a two layer k–ɛ model. The computations...

This paper reports a numerical modeling and simulation studies of film cooling from stream-wise injection holes with various small hole length to diameter ratios, using a standard k-l turbulence model with wall function. An anisotropic model was also applied in order to correct the deficit in lateral spreading of the k-l model. Comparisons of the p...

In this paper hour-by-hour computer simulations of cooling load for a public building were carried out under local weather conditions using TRNSYS building computer simulation software. Different passive measures to reduce the cooling load were investigated. These include the envelope insulation, space ventilation, shading, glazing, artificial ligh...

This paper reports a numerical modeling and simulation studies of film cooling from stream-wise injection holes with various small hole length to diameter ratios, using a standard k-e turbulence model with wall function. An anisotropic model was also applied in order to correct the deficit in lateral spreading of the k-e model. Comparisons of the p...

This paper reports on the feasibility of using various Photovoltaic (PV) systems namely; Grid PV (GPV), Stand-Alone PV (SAPV), Grid PV Wind (GPVW) and PV Wind (PVW) for supplying the power requirements of a window-type air-conditioning system or other small loads. It was found that the GPVW system is the best system to meet the load requirement of...

This paper reports the use of a mathematical model to predict the productivity of a simple solar still under different climatic, design and operational parameters in Oman. The shallow water basin, 23° cover tilt angle, 0.1 m insulation thickness and asphalt coating of the solar still were found to be the optimum design parameters that produced an a...

This paper reports the use of two mathematical models to compare the productivity of single-effect and double-effect solar stills under different climatic, design and operational parameters in Oman. The shallow water basin, 23° cover tilt angle, 0.1 m insulation thickness, and asphalt coating of the solar still were found to be the optimum design p...

Typical film-cooling configurations of flat plates from one and two staggered rows of simple and compound angle injection holes are investigated using a three-dimensional finite volume method and a multiblock technique, which reduces significantly the core memory needed for the computations and gives more freedom in the generation of the grids. The...