Heat transfer from an obliquely impinging circular, air jet to a flat plate

A series of experiments was conducted for the measurement of local convective heat transfer coefficients for an obliquely impinging circular air jet to a flat plate. In the experiments, the oblique angles selected were 90°, 75°, 60° and 45°, with 90° being a vertical jet. Two different Reynolds numbers of 10,000 and 23,000 were considered for the purpose of comparison with previous data available in the literature. Another parameter varied in the measurements was the dimensionless jet-to-plate distance, L/D. Four values of L/D(2, 4, 7, and 10) were considered in the experiments. The experiments were conducted using the preheated wall transient liquid-crystal technique. Liquid-crystal color changes were recorded with a video system. Local convective heat transfer coefficients were obtained through the surface transient temperatures that were related to the recorded color information. Detailed local heat transfer coefficients were presented and discussed in relation to the asymmetric wall jet upon impingement of the jet flow. Results of experiments show that, for a given flow situation, the point of maximum heat transfer shifts away from the geometrical impingement point toward the compression side of the wall jet on the axis of symmetry. The shift is more pronounced with a smaller oblique angle (larger jet inclination) and a smaller jet-to-plate distance. Comparisons of experimental results with existing heat transfer data for both obliquely impinging jets and vertical impinging jets are made. The effect of oblique angles on heat transfer was assessed.     

Heat transfer from a flat surface to an inclined impinging jet

An experimental study was carried out to investigate the effect of the inclination jet on convection heat transfer to horizontal flat plate. Local heat transfer determined as a function is of three parameters including inclination angle of the air jet relative to the plate in range of 90° ≤ θ ≤ 45°, jet-to-plate spacing in range of 2 ≤ L/D ≤ 8 and Reynolds number in range of 1,500 ≤ Re ≤ 30,000. The results show that the maximum heat transfer point moves towards the uphill side of the plate and the maximum heat transfer decreases as the inclination angle decreases. The correlations were conducted to predict maximum and local Nusselt number as a function of Re, θ, L/D, and x/D for a specific three regions.     

Heat transfer between an impinging jet and a continuously moving flat surface

Experiments have been carried out to determine heat transfer rates from a continuously moving belt to an air jet impinging normally. The parameters that were varied included the jet velocity (4 < V_N < 40 m/s), the jet width (4.8 < B < 19 mm), the nozzle-to-plate distance (3 < H/2B < 11) and the belt speed (0. 15 < V_B < 5. 5 m/s). An infrared thermometer was used for the measurement of temperature of the moving belt. The average heat transfer coefficients increase with belt speed steeply initially to a maximum value and then remain almost constant for all higher belt speeds. The maximum heat transfer coefficients are about 1.5 to 2.0 times higher than those predicted for the stationary surface. The present data on continuously surface in still air and in impinging jet flow are well compared with the data on rotating cylinders reported in the literature.

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Wärmeübergang zwischen einem senkrecht auftreffenden Strahl und einer bewegten Oberfläche

Zusammenfassung Experimentell bestimmte Wärmeübergangskoeffizienten für Düsengeschwindigkeiten zwischen 4 m/s und 40 m/s, sowie Düsenbreiten zwischen 4,8 mm und 19 mm lagen bei Bandgeschwindigkeiten zwischen 0, 15 m/s bis 5, 5 m/s ca. 50 % bis 100 % höher als bei unbewegtem Band. Die gemessenen Daten bei bewegtem wie bei unbewegtem Band schließen gut an bekannte Werte aus der Literatur an.

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Nomenclature A Heat transfer area - B Width of the nozzle - D Diameter of the cylinder or equivalent diameter of the flat surface (D=L/) - k Thermal conductivity - Gr Grashof number - h Heat transfer coefficient - H Height of the nozzle from the surface - i Number of nozzles - L Heat transfer length of a flat surface - Nu_D Nusselt number hD/k - Re_DB Belt Reynoldsnumber, DV_B/ - Re_DN Nozzle Reynolds number, DV_N/ - Re_SN Nozzle Reynolds number, SV_N/ - S Hydraulic diameter of the nozzle, 2B - V_B Belt velocity or circumferential velocity of a cylinder - V_N Nozzle celocity - Kinematic viscosity     

Heat transfer due to a round jet impinging normal to a circular cylinder

An experimental investigations of heat transfer for a stationary isothermal circular cylinder exposed normal to an impinging round air-jet has been reported. The circumferential heat transfer distributions as well as axial Nusselt number is measured. The measurements are taken as a function of the Reynolds number ranging from 3.8 × 10³ to 4 × 10⁴, the cylinder separation distance to the nozzle diameter (z/d) varying from 7 to 30, and the nozzle to cylinder diameter ratio (d/D) changing from 0.06 to 0.14. The output results indicated that the axial and radial distributions of the local heat transfer peaked at the impingement point. The heat transfer rate increases as the values of z decreases, for the same d and Re. The drop-off of the Nusselt number with increasing axial distance or radial angle from the impingement point was more pronounced for smaller z and d. The peripheral and surface average Nusselt numbers were determined by integration. The experimental data was used to produce correlations for both average and stagnation point heat transfer. Received on 4 January 1999     

Heat transfer characteristics of premixed butane/air flame jet impinging on an inclined flat surface

 A series of experiments were carried out to determine the heat transfer characteristics of a round, premixed butane/air flame jet impinging upwards on an inclined flat plate, at different angles of incidence. The flame was fixed with an equivalence ratio of 1.0, a Reynolds number of 2500 and a plate-to-nozzle distance of 5d, while the inclination angles chosen for investigation were 57°, 67°, 80° and 90°. It was found that the location of the maximum heat flux point would be shifted away from the geometrical impingement point by reducing the angle of incidence. Decreasing the angle of incidence also enhanced the maximum local heat flux, while reduced the average heat transfer. The present study presented the effect of angle of incidence on the heat transfer characteristics of an impinging butane/air flame jet, which had been rarely reported in previous similar studies. Received on 11 October 2000 The authors wish to thank The Hong Kong Polytechnic University for the financial support of the present study.     

Heat (mass) transfer between an impinging jet and a rotating disk

The aim of this experimental study is to investigate the heat (mass) transfer of a rotating disk with an impinging circular jet. To facilitate the experiments, the naphthalene sublimation technique was employed. In order to analyze the results, measurements of the heat (mass) transfer of a stationary disk with an impinging jet and a rotating disk without jet impingement were also made. From the experimental results, it is found that the heat (mass) transfer are precisely divided into three regimes, namely the impingement dominated regime; the mixed regime and the rotation dominated regime. Correlation of Sherwood number of a rotating disk with jet impingement is also proposed in the present work. Received on 12 January 1998     

Heat transfer and pressure distributions of an impinging jet on a flat surface

Experiments were conducted to determine the heat transfer and surface pressure characteristics of a round jet impinging normal on isothermal flat plate. Three nozzles of exit diameters 3, 5 and 7?mm have been used. The local heat transfer rates have been estimated from the outputs of three-wire differential thermocouple heat flux sensors. The results cover a Reynolds number range of 3400 to 41?000 and dimensionless separation distances varies from 6 to 58. The static pressure distributions along the impingement surface are found to be similar and closer to the heat transfer variations at the same configurations. A simple correlation is derived for the average heat transfer coefficients within ±10% deviation from the output data covering the complete range of experimental limits. The predicted values of Nusselt number have also been compared with the results obtained from the literature. The agreement was generally good.     

Prediction of stagnation point heat transfer for a slot jet impinging on a flat surface

The fluid flow and heat transfer for a slot jet impinging on a flat plate has been analysed for different nozzle-to-plate spacing. The available potential flow solution has been used to solve the boundary layer and energy equations by using the Blasius-Frossling series solution method. The friction factor and Nusselt number have been evaluated as a function of the dimensionless distance from the stagnation point. Correlation for the Stanton number at the Stagnation point, is obtained in terms of velocity gradient at the stagnation point and Reynolds number.

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Berechnung des Wärmeübergangs am Staupunkt für einen Strahl, der senkrecht auf eine ebene Fläche trifft

Zusammenfassung Für einen Fluidstrahl, der senkrecht auf eine ebene Platte trifft, wurden für verschiedene Anordnungen von Düse und Platte Strömung und Wärmeübertragung untersucht. Die beschreibende Potentialtheorie wurde verwendet, um die Grenzschicht und Energiegleichungen mit Hilfe der Blasius-Frossling-Reihenentwicklung zu lösen. Reibungsfaktor und Nusseltzahl sind als eine Funktion des dimensionslosen Abstandes vom Staupunkt dargestellt. Die Beziehung für die Stanton-Zahl am Staupunkt ist in den Ausdrücken des Geschwindigkeitsgradienten am Staupunkt und der Reynoldszahl enthalten.

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Nomenclature A ₁ dimensionless coefficient - a dimensionless parameter - b dimensionless parameter - C _f friction factor,C _f= ₀/(1/2w ² ) - C _p specific heat at constant pressure - F ₀ function ofPr and - G ₄ function ofPr and - f ₁ function of - h heat transfer coefficient - k thermal conductivity - l half-width of slot nozzle - Nu Nusselt number,Nu=hl/k - Pr Prandtl number,Pr=v/ - Re Reynolds number,Re=w l/v - St Stanton number,St=Nu/(Re · Pr) - t temperature - t _w wall temperature - t ambient temperature - U dimensionless velocity,U=u/w - U _f dimensionless free-stream velocity,U _f =u _f /w - U _s dimensionless mainstream velocity along the plate,U _s =u _s /w - u velocity component inx-direction - u _f free stream velocity - u _s mainstream velocity along the plate - w velocity component inz-direction - w velocity at the nozzle exit - x coordination along the plate - X dimensionless distance from the stagnation point along the plate,X=x/l - Y ratio ofU _s andU _f ,Y=U _s /U _f - z coordinate perpendicular to the plate - z _n height of the nozzle above the plate - Z dimensionless height of the nozzle above the plate,Z=z _n /l - thermal diffusivity,=k/( C _p) - dimensionless parameter - dimensionless coordinate perpendicular to the plate - viscosity - kinematic viscosity - ₀ shear stress at the wall - stream function     

Turbulent jet impinging a cylindrical hot cavity

The possibility of improving the heat transfer is investigated numerically using finite volume method. The Reynolds number increase has a minor effect on flow structure but generates a systematic rise of Nusselt Number. The maximum heat exchange occurs when the cavity bottom is located at the potential core end. The main heat exchange occurs on the cavity bottom for every case. The stagnation Nusselt number is correlated according some problem parameters.     

Heat transfer to an unconfined ceiling from an impinging buoyant diffusion flame

Impinging flames are used in fire safety research, industrial heating and melting, and aerospace applications. Multiple modes of heat transfer, such as natural convection, forced convection and thermal radiation, etc. are commonly important in those processes. However, the detailed heat transfer mechanisms are not well understood. In this paper, a model is developed to calculate the thermal response of an unconfined nonburning ceiling from an impinging buoyant diffusion flame. This model uses an algorithm for conduction into the ceiling material. It takes account of heat transfer due to radiation from the fire source to the ceiling surface, and due to reradiation from the ceiling surface to other items. Using experimental data, the convective heat transfer coefficient at lower surface is deduced from this model. In addition, the predicted heat fluxes are compared with the existing experimental data, and the comparison results validate the presented model. It is indicated that this model can be used to predict radial-dependent surface temperature histories under a variety of different realistic levels of fire energy generation rates and fire-to-ceiling separation distance.     

Heat transfer during transient cooling of high temperature surface with an impinging jet

 An experimental study of transient boiling heat transfer during a cooling of a hot cylindrical block with an impinging water jet has been made at atmospheric pressure. The experimental data were taken for the following conditions: a degree of subcooling of ΔT _sub = 20–80 K, a jet velocity of u _j  = 5–15 m/s, a nozzle diameter of d _j  = 2 mm and three materials of copper, brass and carbon steel. The block was initially and uniformly heated to about 250 °C and the transient temperatures in the block were measured at eight locations in r-direction at two different depths from the surface during the cooling of hot block. The surface heat flux distribution with time was evaluated using a numerical analysis of 2-D heat conduction. Behavior of the wetting front, which is extending the nucleate boiling region outward, is observed with a high-speed video camera. A position of wetting region is measured and it is correlated well with a power function of time. The changes in estimated heat flux and temperature were compared with the position of wetting region to clarify the effects of subcooling, jet velocity and thermal properties of block on the transient cooling. Received on 17 March 2000     

Prediction of stagnation point heat transfer for a slot jet impinging on a concave semicylindrical surface

A systematic procedure has been laid out for assessment of fluid flow and heat transfer parameters for a slot jet impinging on a concave semicylindrical surface. Based on Walz's modifications of the Karman-Pohlhausen integral method, expressions have been derived for evaluation of the momentum thickness, boundary layer thickness and the displacement thickness at the stagnation point. The work then has been extended for the estimation of thermal boundary layer thickness and local heat transfer coefficients. A correlation has been presented for the Nusselt number at the stagnation point as a function of the Reynolds number for different non-dimensional distances from the exit plane of the jet to the impingement surface.

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Berechnung des Wärmeübergangs im Staupunkt eines Strahles, der aus einer rechteckigen öffnung auf eine konkave halbzylindrische Fläche auftrifft

Zusammenfassung Es wurde eine systematische Prozedur für die Abschätzung von Strömungs- und Wärmeübergangsparametern für einen Strahl, der auf eine konkave halbzylindrische Fläche auftrifft, aufgestellt. Basierend auf Walz's Modifikationen der Karman-Pohlhausen Integral-Methode, wurden Ausdrücke für die Berechnung der Impulsdicke, der Grenzschichtdicke und die Versetzungsdicke am Staupunkt abgeleitet. Die Arbeit wurde dann auf die Abschätzung der thermischen Grenzschichtdicke und der lokalen Wärmeübertragungskoeffizienten ausgedehnt. Es wird eine Beziehung für die Nusselt-Zahl am Staupunkt als eine Funktion der Reynolds-Zahl für verschiedene dimensionslose Abstände von der Austrittsfläche des Schlitzes bis zur Aufprallfläche aufgestellt.

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Nomenclature c _p specific heat at constant pressure - h ₀ heat transfer coefficient at the stagnation point - H distance from the exit plane of the jet to the impingement surface - k thermal conductivity - Nu _.5 Nusselt number based on impinging jet quantities =h _0.50/k - Nu _.5,0 stagnation point Nusselt number =h _{0 0.50}/k - p pressure - p _a ambient pressure - p ₀ maximum pressure or stagnation pressure - p(x) static pressure at a distancex from the stagnation point - p(x*) static pressure at nondimensional distancex* from the stagnation point - Re _J jet Reynolds number =U _J W/ - Re _0.5 Reynolds number based on impinging jet quantities =u _{m0 0.50}/ - T temperature - T* nondimensional temperature =(T–T _W)/(T _J–T _W) - T _a room temperature - T _J jet temperature - T _W wall temperature - u velocity component inx andx directions - u _m jet centerline (or maximum) free jet velocity: external (or maximum) boundary layer velocity aty = _m - u _m0 arrival velocity defined as the maximum velocity the free jet would have at the plane of impingement if the plane were not there - U _J jet exit velocity - W jet nozzle width - x* nondimensional coordinate starting at the stagnation point =x/2 _0.50 - x, y rectangular cartesian coordinates - y coordinate normal to the wall and starting at the wall - ratio of thermal to velocity boundary layer thickness = _T/ _m - ₀ ratio of thermal to velocity boundary layer thickness at the stagnation point - * inner layer displacement thickness - _.50 jet half width at the plane of impingement if the plate were not there - d_.5 free jet (half width) thickness whereu=u _m/2 - _m inner boundary layer thickness atu =u _m - _T thermal boundary layer thickness - nondimensional coordinate normal to wall =y/ _m - _T nondimensional coordinate normal to wall =y/ _T - Pohlhausen's form parameter - dynamic viscosity - kinematic viscosity = / - fluid density - momentum thickness - ₀ momentum thickness at the stagnation point     

Flow structure and heat transfer characteristics of an unconfined impinging air jet at high jet Reynolds numbers

The flow and heat transfer characteristics of an unconfined air jet that is impinged normally onto a heated flat plate have been experimentally investigated for high Reynolds numbers ranging from 30,000 to 70,000 and a nozzle-to-plate spacing range of 1–10. The mean and turbulence velocities by using hot-wire anemometry and impingement surface pressures with pressure transducer are measured. Surface temperature measurements are made by means of an infrared thermal imaging technique. The effects of Reynolds number and nozzle-to-plate spacing on the flow structure and heat transfer characteristics are described and compared with similar experiments. It was seen that the locations of the second peaks in Nusselt number distributions slightly vary with Reynolds number and nozzle-to-plate spacing. The peaks in distributions of Nusselt numbers and radial turbulence intensity are compatible for spacings up to 3. The stagnation Nusselt number was correlated for the jet Reynolds number and the nozzle-to-plate spacing as Nu _st∝Re ^0.69(H/D)^0.019.     

Heat transfer augmentation between impinging circular air jet and flat plate using finned surfaces and vortex generators

An experimental investigation is performed to study the effect of the finned surfaces and surfaces with vortex generators on the local heat transfer coefficient between impinging circular air jet and flat plate. Reynolds number is varied between 7000 and 30,000 based on the nozzle exit condition and jet to plate spacing between 0.5 and 6 nozzle diameters. Thermal infrared imaging technique is used for the measurement of local temperature distribution on the flat plate. Fins used are in the form of cubes of 2 mm size spaced at a pitch of 5 mm on the target plate and hexagonal prism of side 2.04 mm and height of 2 mm spaced at a pitch of 7.5 mm. Vortex generators in the form of a equilateral triangle of side 4 mm are used. Effect of number of rows of vortex generators, radius of a row, number of vortex generators in a row and inclination angle (i.e., the angle between the plane of the target plate and the plane of the vortex generators) on Nusselt number is studied. It is observed that the heat transfer coefficient between the impinging jet and the target plate is sensitive to the shape of the fin. The increase in the heat transfer coefficient up to 77% depending on the shape of the fin, nozzle plate spacing and the Reynolds number is observed. The augmentation in the heat transfer for the surfaces vortex generators are higher than that of the finned surfaces. The heat transfer augmentation in case of vortex generator is as high as 110% for a single row of six vortex generators at a radius of 1 nozzle diameter as compared to the smooth surface at a given nozzle plate spacing of 1 nozzle diameter and a Reynolds number of 25,000 at extreme radial location.     

Large eddy simulation of a slot jet impinging on a convex surface

A large eddy simulation is used to simulate flow and heat transfer in a turbulent plane jet with two distances from the jet-exit to impingement corresponding to twice and ten times the slot nozzle width. The resolved different unsteady vortex motions of the jet shear layers are studied and shown to have an important influence on heat transfer at the wall. They are used to explain existence of the second peak in Nusselt number for the case corresponding to twice the slot nozzle width. The predicted average surface Nusselt number profiles exhibit good agreement with experiments.     

Experimental investigations of fluid flow and heat transfer characteristics of a slot jet impinging on a square cylinder

Experimental investigations on pressure distributions and average heat transfer on square cylinders due to slot jet impingement have been carried out for different parameters such as, slot jet-width, distance of the square cylinder from the nozzle exit, angle of inclination of the cylinder to the jet axis and Reynolds numbers. The minimum value of the pressure coefficient is obtained on the lower face at an angle of inclination of 15° for all distances of the square cylinder from the nozzle exit. At the lowest Reynolds number the maximum average heat transfer rate is obtained at a distance of eight times the jet width from the nozzle exit. An increasing trend of the heat transfer rate is observed for higher Reynolds numbers. The maximum value of the heat transfer rate is obtained between the angles of inclination of 15° and 30° of the square cylinder to the jet axis. A correlation for the average Nusselt number is proposed in terms of the relevant non-dimensional parameters.

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Experimentelle Untersuchung der Strömungs- und Wärmeübergangscharakteristik bei Schlitzdüsenanblasung eines quadratischen Zylinders

Zusammenfassung Druckverteilung und gemittelter Wärmeübergang bei Schlitzanblasung eines quadratischen Zylinders wurden experimentell für folgende Parameter untersucht: Schlitzbreite; Abstand Düsenmündung vom Zylinder; Neigungswinkel des Zylinders zur Strahlachse; Reynoldszahl. Den Minimalwert des Druckkoeffizienten erhält man für alle Abstände an der Unterseite (bei einem Neigungswinkel von 15°). Bei der niedrigsten Reynoldszahl tritt der höchste Wert des gemittelten Wärmestroms in einem Abstand Düsenmündung/Zylinder von 8 Strahlbreiten auf. Mit steigender Reynoldszahl nimmt der Wärmestrom zu. Dessen höchster Wert tritt im Bereich 15 bis 30° des Neigungswinkels zwischen Zylinder und Strahlachse auf. Eine die Meßwerte korrelierende Nusscltbeziehung als Funktion dimensionsloser Parameter wird angegeben.

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Nomenclature A surface area of the square cylinder - a width of the square cylinder - C _p pressure coefficient=(p–p _a )/ - C _pb base pressure coefficient=(p _b –p _a )/ - h _f free convection heat transfer coefficient - average heat transfer coefficient - k thermal conductivity of air - L distance of the axis of the square cylinder from the nozzle exit - l length of the square cylinder - Pr Prandtl number - p static pressure - p _a atmospheric pressure - p _b base pressure on the rear face - Nu _f free convection Nusselt number - average Nusselt number - q heat loss - q _f heat loss due to free convection - Re Reynolds number=u _j W/v _a - T _a ambient air temperature - average surface temperature - u _j average jet velocity at the nozzle exit - W nozzle width - angle of inclination of the square cylinder to the jet axis in degrees - _a kinematic viscosity of air - _a density of air     

Experimental investigations of fluid flow and heat transfer characteristics of a slot jet impinging on a rectangular cylinder

Experimental investigations on flow characteristics and average heat transfer due to slot jet impinging on a rectangular cylinder have been carried out for different non-dimensional parameters. The minimum value of the pressure coefficient is found on the lower face of the rectangular cylinder at an angle of inclination of 15°. Drag coefficient calculated from the measured pressure distribution is found to be maximum within a range of breadth/width ratio of 0.67 to 1.5 of rectangular cylinders. The maximum value of heat transfer rate is obtained at the angle of inclination of 15° of the cylinder to the jet axis. An increasing trend of heat transfer rate is observed with higher Reynolds numbers. A correlation of average Nusselt number is presented for rectangular cylinders.

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Experimentelle Untersuchung der Strömungs- und Wärmeübergangs-charakteristik eines auf einen rechteckigen Zylinder auftreffenden Strahls aus einer Schlitzdüse

Zusammenfassung Es wurden experimentelle Untersuchungen des Strömungs- und Wärmeübergangsverhaltens an einem rechteckigen, durch einen Strahl aus einer Schlitzdüse beaufschlagten Zylinders für verschiedene dimensionslose Parameter durchgeführt. Der Kleinstwert des Druckbeiwertes tritt an der Unterfläche des rechteckigen Zylinders bei einem Neigungswinkel von 15° auf. Der ausder gemessenen Druckverteilung berechnete Widerstandsbeiwert erreicht bei einem Breiten-Dicken-Verhältnis des Zylinders zwischen 0,67 und 1,5 Maximalwerte. Den maximalen Wärmestrom erhält man bei einem Neigungswinkel zwischen Zylinder und Strahlachse von 15°. Mit steigenden Reynoldszahlen erhöht sich der abgeführte Wärmestrom. Eine Korrelation für die mittlere Nusseltzahl an rechteckigen Zylindern wird mitgeteilt.

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Nomenclature A surface area of the rectangular cylinder - a width of the rectangular cylinder - b breadth of the rectangular cylinder - C _D drag coefficient =D/ - C _p pressure coefficient = (p – p _a )/ - C _pb base pressure coefficient = (p _b –p _a )/ - D drag force - h _f free convection heat transfer coefficient - average heat transfer coefficient - k thermal conductivity of air - L distance of the axis of the square cylinder from the nozzle exit - l length of the rectangular cylinder - Pr Prandtl number - p static pressure - P _a atmospheric pressure - P _b base pressure on the rear face - Nu _f free convection Nusselt number - average Nusselt number - q heat loss - q _f heat loss due to free convection - Re Reynolds number =u _j W/ _a - T _a ambient air temperature - average surface temperature - u _j average jet velocity at the nozzle exit - W nozzle width - angle of inclination of the rectangular cylinder to the jet axis in degrees - _a kinematic viscosity of air - _a density of air     

Simulation of glass cutting with an impinging hot air jet

Thermal cutting of glass sheet due to an impinging hot air jet is simulated and analyzed. Induced thermal stresses due to the moving heat source can be used to stably initiate and attract a crack toward the jet axis. Relative motion between the jet and glass sheet then can be used to cut the glass sheet. This paper presents a theoretical study of this process for straight cuts. Process simulation is accomplished by analyzing the coupled temperature and stress fields together with the fracture mechanics criteria for the crack growth.A finite element remeshing technique is employed for the analysis and singular elements are used around the crack tip for a more precise computing of the stress intensity factor. It is shown that a certain minimum air jet temperature for a given nozzle velocity and a certain maximum air jet velocity for a given temperature are required for continuous cutting. The results of the simulation show a good agreement with the published results in the literature. However a variating nature is detected for the distance between the crack tip and the air jet nozzle from a starting value to the steady-state one.