This page has only limited features, please log in for full access.
This paper presents a numerical investigation on the momentum and thermal characteristics of an intercooler connection hose that is in use in the 1.3 SDE 75 CV type FIAT engine. Computational analyses are carried out with ANSYS FLUENT v.12.0.1, where both stationary and vibrating scenarios are handled. The work is structured in accordance with the “Subsystem Functional Description for Charge Air Hoses Fiat 225 Euro 5” FIAT standard, where the air mass flow rate, temperature, and gage pressure at the hose inlet are identified as \( {\mathop m\limits^ \cdot }\) = 0.085 kg/s, T in = 90°C, and P in = 130 kPa, respectively. In the stationary case, it is determined that the pressure loss value in the air domain of the hose is ΔP K = 1.50 kPa; moreover, the corresponding data for the temperature drop is ΔT = 0.80°C. Vibration is characterized by employing simple harmonic motion at the engine side of the hose. The fluid–solid interaction methodology showed that pressure loss values grow due to vibration; moreover, the impact of vibration came out to generate diverse fluctuation schemes at different sections of the hose.
Alper Uysal; A. Alper Ozalp; Ayhan Korgavus; Orhan Korgavus. Numerical modeling of the momentum and thermal characteristics of air flow in the intercooler connection hose. The International Journal of Advanced Manufacturing Technology 2011, 60, 811 -824.
AMA StyleAlper Uysal, A. Alper Ozalp, Ayhan Korgavus, Orhan Korgavus. Numerical modeling of the momentum and thermal characteristics of air flow in the intercooler connection hose. The International Journal of Advanced Manufacturing Technology. 2011; 60 (5-8):811-824.
Chicago/Turabian StyleAlper Uysal; A. Alper Ozalp; Ayhan Korgavus; Orhan Korgavus. 2011. "Numerical modeling of the momentum and thermal characteristics of air flow in the intercooler connection hose." The International Journal of Advanced Manufacturing Technology 60, no. 5-8: 811-824.
Energy and exergy mechanisms of laminar-transitional micropipe flows are computationally investigated by solving the variable fluid property continuity, Navier–Stokes and energy equations. Analyses are carried for wide ranges of Reynolds number (Re = 10–2,000), micropipe diameter (d = 0.50–1.00 mm), non-dimensional surface roughness (ε* = 0.001–0.01) and wall heat flux ( \( {\text{q}}^{\prime \prime } \) = 1,000–2,000 W/m2) conditions. Computations revealed that friction coefficient (Cf) elevates with higher ε* and Re and with lower d, where the rise of ε* from 0.001 to 0.01 induced the Cf to increase by 0.7 → 0.9% (d = 1.00 → 0.50 mm), 3.4 → 4.2%, 6.6 → 8.1%, 9.6 → 11.9% and 12.4 → 15.2% for Re = 100, 500, 1,000, 1,500 and 2,000, respectively. Earlier transition exposed with stronger micro-structure and surface roughness at the descriptive transitional Reynolds numbers of Re tra = 1,656 → 769 (ε* = 0.001 → 0.01), 1,491 → 699 and 1,272 → 611 at d = 1.00, 0.75 and 0.50 mm; the corresponding shape factor (H) and intermittency (γ) data appear in the narrow ranges of H = 3.135–3.142 and γ = 0.132–0.135. At higher Re and lower d, ε* is determined to become more influential on the heat transfer rates, such that the Nuε*=0.01/Nuε*=0.001 ratio attains the values of 1.002 → 1.023 (d = 1.00 → 0.50 mm), 1.012 → 1.039, 1.025 → 1.056 and 1.046 → 1.082 at Re = 100, 500, 1,000 and 2,000. As ε* comes out to cause minor variations in the cross-sectional thermal entropy generation rates \( \left( {{\text{S}}_{{\Updelta {\text{T}}}}^{\prime } } \right) \) , \( {\text{q}}^{\prime \prime } \) is confirmed to augment \( {\text{S}}_{{\Updelta {\text{T}}}}^{\prime } \) , where the impact becomes more pronounced at higher Re and d. Frictional entropy generation values \( \left( {{\text{S}}_{{\Updelta {\text{P}}}}^{\prime } } \right) \) are found to be motivated by lower d, higher Re and ε*, such that the \( {\text{S}}_{{\Updelta {\text{P}}_{{{\text{d}} = 0.50{\text{mm}}}} }}^{\prime } /{\text{S}}_{{\Updelta {\text{P}}_{{{\text{d}} = 1.00{\text{mm}}}} }}^{\prime } \) ratio is computed as 4.0011 → 4.0014 (ε* = 0.001 → 0.01), 4.002 → 4.007, 4.006 → 4.027 and 4.023 → 4.102 at Re = 100, 500, 1,000 and 2,000. As the role of \( {\text{q}}^{\prime \prime } \) on total entropy generation \( ({\text{S}}^{\prime } ) \) turns out to be more remarkable at higher d and lower Re, the task of ε* becomes more sensible at higher Re.
A. Alper Ozalp. Laminar-transitional micropipe flows: energy and exergy mechanisms based on Reynolds number, pipe diameter, surface roughness and wall heat flux. Heat and Mass Transfer 2011, 48, 17 -34.
AMA StyleA. Alper Ozalp. Laminar-transitional micropipe flows: energy and exergy mechanisms based on Reynolds number, pipe diameter, surface roughness and wall heat flux. Heat and Mass Transfer. 2011; 48 (1):17-34.
Chicago/Turabian StyleA. Alper Ozalp. 2011. "Laminar-transitional micropipe flows: energy and exergy mechanisms based on Reynolds number, pipe diameter, surface roughness and wall heat flux." Heat and Mass Transfer 48, no. 1: 17-34.
The effects of blockage on the hydrodynamic, thermal and mass transfer characteristics of a circular cylinder (CC) and their association with each other are investigated numerically, by considering the influence of blockage (β = 0.333–0.800) on the flow and heat transfer mechanisms in conjunction with moisture diffusivity (D = 1 × 10−8–1 × 10−5 m2/s) to show how much mass transfer behavior and phenomena are affected. As some comprehensive ANSYS-CFX runs are performed in the hydrodynamic and thermal fields around the CC, the moisture distributions within the CC are evaluated by Alternating Direction Implicit method. It is determined that blockage causes thinner hydrodynamic and thermal boundary layers, rises the frictional and thermal activities, and shifts the separation locations (θs) downstream to θs = 50.20°, 41.98° and 37.30° for β = 0.333, 0.571 and 0.800. In the complete blockage scenario set, stagnation point heat transfer values are evaluated to be above those of the back-face, signifying the superior heat transfer enhancing capability of the stagnation point momentum activity when compared with the impact of downstream vortex system. The influence of moisture diffusivity on the overall drying times is determined to advance with stronger blockage. As the back face mass transfer coefficients (hm-bf) rise with a high β, the contrary is valid for front face values (hm-ff), with the interpreting ratios of h¯m-bf/h¯m = 0.51 and 0.57 and h¯m-ff/h¯m = 1.49 and 1.43 for β = 0.333 and 0.800.
A. Alper Ozalp; Ibrahim Dincer. Hydrodynamic-thermal boundary layer development and mass transfer characteristics of a circular cylinder in confined flow. International Journal of Thermal Sciences 2010, 49, 1799 -1812.
AMA StyleA. Alper Ozalp, Ibrahim Dincer. Hydrodynamic-thermal boundary layer development and mass transfer characteristics of a circular cylinder in confined flow. International Journal of Thermal Sciences. 2010; 49 (9):1799-1812.
Chicago/Turabian StyleA. Alper Ozalp; Ibrahim Dincer. 2010. "Hydrodynamic-thermal boundary layer development and mass transfer characteristics of a circular cylinder in confined flow." International Journal of Thermal Sciences 49, no. 9: 1799-1812.
This paper presents a comprehensive computational work on the hydrodynamic, thermal, and mass transfer characteristics of a circular cylinder, subjected to confined flow at the cylinder Reynolds number of Red=40. As the two-dimensional, steady and incompressible momentum and energy equations are solved using ANSYS-CFX (version 11.0), the moisture distributions are computed by a new alternating direction implicit method based software. The significant results, highlighting the influence of blockage (β=0.200–0.800) on the flow and heat transfer mechanism and clarifying the combined roles of β and moisture diffusivity (D=1×10−8–1×10−5 m2/s) on the mass transfer behavior, are obtained for practical applications. It is shown that the blockage augments the friction coefficients (Cf) and Nusselt numbers (Nu) on the complete cylinder surface, where the average Nu are evaluated as Nuave=3.66, 4.05, 4.97, and 6.51 for β=0.200, 0.333, 0.571, and 0.800. Moreover, the blockage shifts separation (θs) and maximum Cf locations (θCf−max) downstream to the positions of θs=54.10, 50.20, 41.98, and 37.30 deg and θCf−max=51.5, 53.4, 74.9, and 85.4 deg. The highest blockage of β=0.800 encourages the downstream backward velocity values, which as a consequence disturbs the boundary layer and weakens the fluid-solid contact. The center and average moisture contents differ significantly at the beginning of drying process, but in the last 5% of the drying period they vary only by 1.6%. Additionally, higher blockage augments mass transfer coefficients (hm) on the overall cylinder surface; however, the growing rate of back face mass transfer coefficients (hm−bf) is dominant to that of the front face values (hm−ff), with the interpreting ratios of h¯m−bf/h¯m=0.50 and 0.57 and h¯m−ff/h¯m=1.50 and 1.43 for β=0.200 and 0.800.
A. Alper Ozalp; Ibrahim Dincer. Laminar Boundary Layer Development Around a Circular Cylinder: Fluid Flow and Heat-Mass Transfer Characteristics. Journal of Heat Transfer 2010, 132, 121703 .
AMA StyleA. Alper Ozalp, Ibrahim Dincer. Laminar Boundary Layer Development Around a Circular Cylinder: Fluid Flow and Heat-Mass Transfer Characteristics. Journal of Heat Transfer. 2010; 132 (12):121703.
Chicago/Turabian StyleA. Alper Ozalp; Ibrahim Dincer. 2010. "Laminar Boundary Layer Development Around a Circular Cylinder: Fluid Flow and Heat-Mass Transfer Characteristics." Journal of Heat Transfer 132, no. 12: 121703.
Fluid flow, heat transfer and entropy generation characteristics of micro-pipes are investigated computationally by considering the simultaneous effects of pipe diameter, wall heat flux and Reynolds number in detail. Variable fluid property continuity, Navier-Stokes and energy equations are numerically handled for wide ranges of pipe diameter (d = 0.50–1.00 mm), wall heat flux (q''= 1000–2000 W/m2) and Reynolds number (Re = 1 – 2000), where the relative roughness is kept constant at e/d = 0.001 in the complete set of the scenarios considered. Computations indicated slight shifts in velocity profiles from the laminar character at Re = 500 with the corresponding shape factor (H) and intermittency values (γ) of H = 3.293→3.275 and γ = 0.041→0.051 (d = 1.00→0.50 mm). Moreover, the onset of transition was determined to move down to Retra = 1,656, 1,607, 1,491, 1,341 and 1,272 at d = 1.00, 0.90, 0.75, 0.60 and 0.50 mm, respectively. The impacts of pipe diameter on friction mechanism and heat transfer rates are evaluated to become more significant at high Reynolds numbers, resulting in the rise of energy loss data at the identical conditions as well. In cases with low pipe diameter and high Reynolds number, wall heat flux is determined to promote the magnitude of local thermal entropy generation rates. Local Bejan numbers are inspected to rise with wall heat flux at high Reynolds numbers, indicating that the elevating role of wall heat flux on local thermal entropy generation is dominant to the suppressing function of Reynolds number on local thermal entropy generation. Cross-sectional total entropy generation is computed to be most influenced by pipe diameter at high wall heat flux and low Reynolds numbers.
A. Alper Özalp. Combined Effects of Pipe Diameter, Reynolds Number and Wall Heat Flux and on Flow, Heat Transfer and Second-Law Characteristics of Laminar-Transitional Micro-Pipe Flows. Entropy 2010, 12, 445 -472.
AMA StyleA. Alper Özalp. Combined Effects of Pipe Diameter, Reynolds Number and Wall Heat Flux and on Flow, Heat Transfer and Second-Law Characteristics of Laminar-Transitional Micro-Pipe Flows. Entropy. 2010; 12 (3):445-472.
Chicago/Turabian StyleA. Alper Özalp. 2010. "Combined Effects of Pipe Diameter, Reynolds Number and Wall Heat Flux and on Flow, Heat Transfer and Second-Law Characteristics of Laminar-Transitional Micro-Pipe Flows." Entropy 12, no. 3: 445-472.
Variable fluid property continuity, Navier–Stokes and energy equations are solved for roughness induced forced convective laminar-transitional flow in a micropipe. Influences of Reynolds number, heat flux and surface roughness, on the momentum-energy transport mechanisms and second-law of thermodynamics, are investigated for the ranges of Re = 1–2,000, Q = 5–100 W/m2 and ε = 1–50 μm. Numerical investigations put forward that surface roughness accelerates transition with flatter velocity profiles and increased intermittency values (γ); such that a high roughness of ε = 50 μm resulted in transitional character at Re tra = 450 with γ = 0.136. Normalized friction coefficient (C f*) values showed augmentation with Re, as the evaluated C f* are 1.006, 1.028 and 1.088 for Re = 100, 500 and 1,500, respectively, at ε = 1 μm, the corresponding values rise to C f* = 1.021, 1.116 and 1.350 at ε = 50 μm. Heat transfer rates are also recorded to rise with Re and ε; moreover the growing influence of ε on Nusselt number with Re is determined by the Nu ε=50 μm/Nu ε=1 μm ratios of 1.086, 1.168 and 1.259 at Re = 500, 1,000 and 1,500. Thermal volumetric entropy generation \( (\bar S_{\Updelta {\text{T}}}^{'''} ) \) values decrease with Re and ε in heating; however the contrary is recorded for frictional volumetric entropy generation \( (\bar S_{\Updelta {\text{P}}}^{'''} ) \) data, where the augmentations in \( \bar S_{\Updelta {\text{P}}}^{'''} \) are more considerable when compared with the decrease rates of \( \bar S_{\Updelta {\text{T}}}^{'''} . \)
A. Alper Ozalp. Roughness induced forced convective laminar-transitional micropipe flow: energy and exergy analysis. Heat and Mass Transfer 2008, 45, 31 -46.
AMA StyleA. Alper Ozalp. Roughness induced forced convective laminar-transitional micropipe flow: energy and exergy analysis. Heat and Mass Transfer. 2008; 45 (1):31-46.
Chicago/Turabian StyleA. Alper Ozalp. 2008. "Roughness induced forced convective laminar-transitional micropipe flow: energy and exergy analysis." Heat and Mass Transfer 45, no. 1: 31-46.
Choked converging nozzle flow and heat transfer characteristics are numerically investigated by means of a recent computational model that integrates the axisymmetric continuity, state, momentum and energy equations. To predict the combined effects of nozzle geometry, friction and heat transfer rates, analyses are conducted with sufficiently wide ranges of covergence half angle, surface roughness and heat flux conditions. Numerical findings show that inlet Mach and Nusselt numbers decrease up to 23.1% and 15.8% with surface heat flux and by 15.13% and 4.8% due to surface roughness. Considering each convergence half angle case individually results in a linear relation between nozzle discharge coefficients and exit Reynolds numbers with similar slopes. Heat flux implementation, by decreasing the shear stress values, lowers the risks due to wear hazards at upstream sections of flow walls; however the final 10% downstream nozzle portion is determined to be quite critical, where shear stress attains the highest magnitudes. Heat transfer rates are seen to increase in the streamwise direction up to 2.7 times; however high convergence half angles, heat flux and surface roughness conditions lower inlet Nusselt numbers by 70%, 15.8% and 4.8% respectively.
A. Alper Ozalp. Numerical analysis of choked converging nozzle flows with surface roughness and heat flux conditions. Sādhanā 2006, 31, 31 -46.
AMA StyleA. Alper Ozalp. Numerical analysis of choked converging nozzle flows with surface roughness and heat flux conditions. Sādhanā. 2006; 31 (1):31-46.
Chicago/Turabian StyleA. Alper Ozalp. 2006. "Numerical analysis of choked converging nozzle flows with surface roughness and heat flux conditions." Sādhanā 31, no. 1: 31-46.
A. Alper Ozalp. Nonadiabatic and frictional constant area duct flow: A visual software based simulation for compressible systems. Computer Applications in Engineering Education 2006, 14, 64 -75.
AMA StyleA. Alper Ozalp. Nonadiabatic and frictional constant area duct flow: A visual software based simulation for compressible systems. Computer Applications in Engineering Education. 2006; 14 (1):64-75.
Chicago/Turabian StyleA. Alper Ozalp. 2006. "Nonadiabatic and frictional constant area duct flow: A visual software based simulation for compressible systems." Computer Applications in Engineering Education 14, no. 1: 64-75.
The purpose of this paper is to propose an optimistic upper surface design, by applying a wavy pattern, for the slider bearing lubrication environment, without going beyond the geometric limits of the complete flow volume. Continuity, momentum and energy equations are handled simultaneously by interpreting the relation of lubricant motion and pressure distribution through a Transfer Matrix; the temperature dependent character of viscosity is considered in the computations with a convergence criterion of 0.01% for two consecutive temperature distributions within the implemented iterative approach. Numerical investigations are carried with wave amplitude and wave number ranges of 0-200 μm and 5-105 respectively and the pumping pressures are 1.01-3.01 times the exit value. The computational results point out an optimum upper surface design with a wave number range of 25-45, which not only increases the load capacity but also decreases the power requirement.
B. Turker Ozalp; A. Alper Ozalp. A Computational Approach on the Multitask Optimization of Inclined Slider Bearing Performance with Upper-Surface-Waviness. Computer Vision 2006, 3743, 526 -534.
AMA StyleB. Turker Ozalp, A. Alper Ozalp. A Computational Approach on the Multitask Optimization of Inclined Slider Bearing Performance with Upper-Surface-Waviness. Computer Vision. 2006; 3743 ():526-534.
Chicago/Turabian StyleB. Turker Ozalp; A. Alper Ozalp. 2006. "A Computational Approach on the Multitask Optimization of Inclined Slider Bearing Performance with Upper-Surface-Waviness." Computer Vision 3743, no. : 526-534.
Critical design parameters on the performance prediction of converging nozzles are the geometric features and the operating conditions, which include the stagnant properties at the inlet, frictional and heat transfer behaviors on the nozzle wall; where the latter two are hard to handle together in compressible high-speed flows. This paper presents a recent computational model, that integrates the axisymmetric continuity, momentum and energy equations, to predict the combined effects of surface roughness and heat flux conditions on the flow and heat transfer characteristics of compressible flows through converging nozzles. To build a comprehensive overview, analyses are conducted at convergence half angles from 0° to 9° and inlet stagnation to back pressure ratios ranged from 1.01 to 2, covering both the un-choked and choked cases. Non-dimensional surface roughness and surface heat flux values are in the order of 0.0025-0.05 and 20-2000 kW/m2 respectively. The influences of the model parameters on the nozzle performance are discussed through the streamwise variations of Mach number, shear stress, discharge coefficient and Nusselt number; to verify the validity of the model comparisons are made with the numerical and experimental data available in the literature.
A. Alper Ozalp. A COMPUTATIONAL STUDY TO PREDICT THE COMBINED EFFECTS OF SURFACE ROUGHNESS AND HEAT FLUX CONDITIONS ON CONVERGING-NOZZLE FLOWS. Transactions of the Canadian Society for Mechanical Engineering 2005, 29, 67 -80.
AMA StyleA. Alper Ozalp. A COMPUTATIONAL STUDY TO PREDICT THE COMBINED EFFECTS OF SURFACE ROUGHNESS AND HEAT FLUX CONDITIONS ON CONVERGING-NOZZLE FLOWS. Transactions of the Canadian Society for Mechanical Engineering. 2005; 29 (1):67-80.
Chicago/Turabian StyleA. Alper Ozalp. 2005. "A COMPUTATIONAL STUDY TO PREDICT THE COMBINED EFFECTS OF SURFACE ROUGHNESS AND HEAT FLUX CONDITIONS ON CONVERGING-NOZZLE FLOWS." Transactions of the Canadian Society for Mechanical Engineering 29, no. 1: 67-80.
The temperature dependent character of viscosity complicates the numerical analysis of hydrodynamic slider bearings and the geometry of the flow cavity plays a significant role on the design and performance of the lubrication systems. In this paper, we represent a recent software tool, named as "HYDRO-LUB," capable of performing constant and variable viscosity runs in various pad styles with moving boundaries. Results of the demonstrating project are not only consistent with the available literature but also show the fast and reliable character of the package; which in return put forward the advantages of applying the program in the lubrication courses of mechanical engineering. © 2003 Wiley Periodicals, Inc
A. Alper Ozalp; S. Ayse Özel. An interactive software package for the investigation of hydrodynamic-slider bearing-lubrication. Computer Applications in Engineering Education 2003, 11, 103 -115.
AMA StyleA. Alper Ozalp, S. Ayse Özel. An interactive software package for the investigation of hydrodynamic-slider bearing-lubrication. Computer Applications in Engineering Education. 2003; 11 (3):103-115.
Chicago/Turabian StyleA. Alper Ozalp; S. Ayse Özel. 2003. "An interactive software package for the investigation of hydrodynamic-slider bearing-lubrication." Computer Applications in Engineering Education 11, no. 3: 103-115.