Convective Heat Transfer Distribution Research Articles

Influence of air flow field computation on an ice accretion simulation of airfoils

Ice accretion simulation is an important research technology for aircraft icing problems. Air flow field prediction of an iced aircraft is an essential step of ice accretion simulation. However, commonly used turbulence models have difficulty predicting the large flow separation of the iced aircraft, which makes air flow field calculation insufficiently accurate and further affects the ice accretion simulation. In this paper, the influence of air flow field computation on ice accretion simulation of airfoils is numerically studied. Several different turbulence models are applied to predict air flow fields of iced airfoils. Then, the Eulerian method of water droplets, integral boundary layer method and Myers model are used to simulate ice accretion. Different airfoils with several icing conditions, including glaze ice and rime ice cases, are numerically tested and compared with experimental data. The results show that the separating shear layer fixed k−ω model is more accurate than other turbulence models in predicting the pressure distribution of the iced airfoil, especially the leading-edge suction peak. Thus, a more reasonable droplet collection efficiency distribution and convective heat transfer distribution can be obtained, yielding a more consistent ice height compared with the experimental data.

Experimental study of convective heat transfer distribution of non-interacting wall and perpendicular air jet impingement cooling on flat surface

An experimental study evaluated heat transfer with perpendicular and wall-impinging air jets on stainless steel foil, for Reynolds numbers Re = 3000, 5000, 8000, and 10000, where the perpendicular jet targets the bottom and the wall jet the top, creating a unique, non-interacting effect. Distances to nozzle diameter ratios for wall jets (S/d = 4, 6, 8, 10) and perpendicular jets (Z/d = 2, 4, 6, 8) were varied. Significant heat transfer increases were noted, with the Nusselt number rising by up to 49.20 % for a Z/d = 6 and S/d = 8 combination at Re = 5000. Improvements ranged from 10.03 % to 49.20 %, peaking when the jets' high heat transfer regions overlapped. Optimal performance for Re = 3000 was at S/d = 10, aligning the wall jet's maximum with the perpendicular jet's stagnation area. For Re = 5000 to 10000, optimal S/d values were 8 and 4 for Z/d = 6, 8 and Z/d = 2, 4, respectively. The Nusselt number increase ranged from 29.21 % to 46.57 % at S/d = 10 for Re = 3000, the highest among all tested values. Wall jet heat transfer downstream increased by 90–105 % over perpendicular jets in corresponding regions. Increasing the wall to perpendicular jet distance improved heat transfer near the stagnation point, suggesting this cooling method for high-density electronics like CPUs and GPUs.

Methodology for determining convective heat transfer coefficients on the tubesheet surface of shell-and-tube heat exchangers under single-phase flow

Designing shell-and-tube heat exchangers requires reliable methods to calculate the convective heat transfer coefficient (CHTC) on the tubesheet, due to its impact on thermal stress. To address this, we established numerical models for both the tube and shell sides of the tubesheet. Using computational fluid dynamics (CFD), we systematically investigated the distribution of convective heat transfer on the tubesheet surface and its variations with structural and process parameters. The results showed that when fluid flowed into the tubesheet, the average convective heat transfer coefficient on the tube side of the tubesheet surface was 26% higher than when it flowed out. Additionally, the average convective heat transfer coefficient in the perforated region of the tubesheet was 1.39 to 2.57 times greater than in its periphery. Furthermore, the local CHTC on the shell side of the tubesheet surface gradually decreased along the downstream direction from the inlet of the shell-side fluid. Through simulations conducted across various structural and process parameters, we derived empirical formulas to rapidly calculate the average CHTC on the tubesheet surface. These formulas incorporated a tubesheet porosity factor for the tube side and introduced a new method for calculating the equivalent tubesheet diameter on the shell side. Random testing verified that our proposed formula reliably predicted the numerical simulation results.

Synchronized measurement of instantaneous convective heat flux and velocity fields in wall-bounded flows

This work presents an experimental setup for acquiring synchronized wall and flow field measurements in a turbulent boundary layer (TBL). Instantaneous measurements of the convective heat transfer distribution at the wall and of the flow field are carried out simultaneously, using synchronized wall-parallel planar particle image velocimetry and infrared thermography. A low-thermal-inertia heated-thin-foil sensor is embedded in the wall beneath the TBL to measure the wall temperature maps with enough temporal resolution. The unsteady energy balance of the heated foil can be solved to restore the instantaneous value of the convective heat transfer coefficient on the wall. A detailed description of the sensor design is included. Furthermore, owing to the relatively low signal-to-noise ratio of instantaneous temperature fluctuation measurements, a recipe for data processing is proposed. A study to characterize the uncertainty of the experimental setup design is also performed. The overall agreement in the correlation between wall heat transfer and velocity fields with the literature supports the validity of the proposed approach. This solution is potentially interesting for flow control purposes, where sensing is performed at the wall.

THREE-DIMENSIONAL NUMERICAL ANALYSIS OF FLOW AND HEAT TRANSFER CHARACTERISTICS OF OIL/GAS TWO-PHASE MIXTURE IN AERO-ENGINE BEARING CHAMBERS OF DIFFERENT STRUCTURES

The change of the outlet number of bearing chambers can change the pressure distribution in the chamber and the action of the air shear force, which has an important influence on oil/gas two-phase flow and heat transfer. In this paper, the flow and heat transfer characteristics in the ventless bearing chamber and the vented bearing chamber were compared and analyzed by numerical simulation. The accuracy of the numerical model was verified by comparison with the experimental data. Three different rotor speeds were selected, and the lubricating oil distribution, the velocity of oil/gas two-phase flow, and the temperature distribution in the bearing chamber were investigated under different numbers of outlets of the bearing chamber. The heat flux and Nusselt number distribution of convective heat transfer between oil/gas two-phase flow and the outer wall at different rotor speeds were analyzed. The results show that the thickness of oil film increases in the ventless bearing chamber with increase of rotor speed, and when air flow is large, it hinders the uniformity of lubricating oil distribution and the increase of the velocity of oil/gas two-phase flow, but it can improve the uniformity of heat transfer. In the vented bearing chamber, the thickness of oil film decreases with increase of rotor speed, and the speed of oil/gas two-phase flow increases greatly, and the entraining effect of air is obvious. The research results can provide a theoretical reference for improving the number and structure of bearing chambers to improve the performance of lubricating oil system.

The Contaminate Infiltration Model for Heat and Concentration Transport Within Porous Media Under Electromagnetic Fields

Abstract This paper studies the groundwater model of the influence of physical parameters, including input frequency of the electromagnetic, and input concentration of contaminants in groundwater, on the velocity pattern, temperature distribution, and concentration distribution of convective heat transfer in saturated porous media as soil. The mathematical models have solved seven equations in this simulation study, i.e., Maxwell's equation, heat transfer in fluid and solid phases, momentum, and concentration equations. The effect of frequencies and input concentrations of contaminants on the convective heat transfer and concentration distribution in porous media as soil under an electromagnetic wave is investigated. The results indicate that the electromagnetic wave frequency of 2.45 GHz has the most influence on the temperature distribution, velocity patterns, and concentration distribution of the fluid within the porous media as soil during saturated flow in groundwater. The inlet fluid concentration of the contaminant at 30 mol/dm3 has the most impact on the temperature distribution between the implementation of an electromagnetic wave of 2.45 GHz. So, this numerical model provides simple decision data based on comparing the maximum contaminant concentrations of porous media as soil samples with surface soil screening levels such as petroleum engineering and agricultural engineering. This result can be used by the engineer as a guide to determine whether further investigation is needed.

Numerical study of convective heat transfer and particle distribution subject to magneto-static field in a square cavity

Magnetic nanoparticle suspension has been applied in a variety of energy transport systems due to its excellent flowing characteristics and extraordinary thermal conductivity, and it has proven to significantly influence the sustainable development of energy and the environment. This work aims to focus on the thermal, fluidic properties of the magnetic nanofluid while also considering the coupling factors of magnetic field, thermal exchange, fluidity and nanoparticle concentration. Firstly, the simulation results of velocity and temperature distribution will be validated using the finite element method, which is in accordance with previous results of natural convection in a square cavity. The analysis model of developed magneto-hydrodynamics heat transfer will then be constructed with the explanation of entropy and concentration distribution. In comparison to natural convection, the magnetic field-enhanced method is able to break through the limit of thermal exchange efficiency. In addition, when the magnetic field is increased to 30 kA/m, the thermodynamic force is replaced by magnetic volumetric force and this plays a role in the heat transfer of the cavity, while the average Nusselt numbers increase by 17% in comparison to natural convection performance (Ra = 105). Entropy generation increases as magnetic field strength increases as a result of the enhancement to circulation and temperature gradient in the nanofluid. This work utilises an advanced strategy for the convection performance of magnetic nanofluid and analyses the multi-physical field.

Heat transfer experiments and correlations for vent gases emerging from a Li-ion battery and impinging on a flat surface

During thermal runaway of Li-ion battery cells, high-temperature gas jets may impinge onto nearby surfaces and may increase the risk of a propagating failure. In this paper, heat transfer rates of jets emerging from a cylindrical Li-ion cell and impinging on a flat surface were measured experimentally and empirical correlations were developed based on the resulting data. Experiments used compressed air as the working fluid, which issued from the isolated safety vent and impinged on a target plate. Infrared thermography was used to obtain the spatially-resolved, convective heat transfer distribution on the target plate. While heat transfer distributions showed local maxima at the site of jet impingement, complex geometric features within the vent resulted in variation in the convection rate when comparing the multiple impinging jets emerging from a single Li-ion cell. Heat transfer correlations were developed in the form of Nusselt number as a function of Reynolds number and may be used in thermal runaway models which seek to include the effects of venting and combustion as an alternative to resolving the impingement heat transfer rates with expensive 3-D computational fluid dynamics simulations.

Experimental assessment of the gap width effect on turbulent flow and forced convective heat transfer around a single rod suspended in a channel

The present work presents the experimental campaign carried out to assess the convective heat transfer around a single rod suspended in a rectangular channel under axial turbulent flow. The distance between the rod and the upper wall of the channel forms a rod-wall gap, whose width, d, can be varied. The experiments were performed for the dimensionless gap widths that yield W/D = 1.050, 1.100, 1.150 and 1.200. Hot-wire anemometry was used to measure mean velocities, the RMS velocity fluctuations and the velocity spectra. The rod is equipped with a heated cell that provides the local temperature and convective heat transfer coefficient distributions around the rod’s surface. The local convective heat transfer distribution is in good agreement with the literature. The lowest value for the heat transfer coefficient was not found right in the narrow gap for W/D = 1.050, but, slightly away from the gap. As W/D increases, the minimum local convective heat transfer coefficient occurred closer to the narrowest gap width. The Reynolds-Colburn analogy was investigated for all configurations through the measured convective heat transfer coefficient and the skin friction distributions. A linear relationship was found between the Stanton number and the skin friction coefficient. Moreover, data scattering was seen to decrease significantly when the local velocity was used instead of the global one. It suggests that the heat transfer process is governed, mainly, by the local parameters.

Reducing turbulent convective heat transfer with streamwise plasma vortex generators

The effect of streamwise plasma vortex generators on the convective heat transfer of a turbulent boundary layer is experimentally investigated. A Dielectric Barrier Discharge (DBD) plasma-actuator array is employed to promote pairs of counter-rotating, streamwise-aligned vortices embedded in a well-behaved turbulent boundary layer over a flat plate. The study aims at elucidating the mechanism of interaction between the plasma-induced vortical structures and the convective heat transfer process downstream of them. The full three-dimensional mean flow field is measured with planar and stereoscopic PIV. The convective heat transfer is assessed with infrared thermography over a heat-flux sensor located downstream of the actuators. The combination of the flow field and heat transfer measurements provides a complete picture of the fluid-dynamic interaction of plasma-induced flow with local turbulent transport effects. The results show that the streamwise vortices are stationary and confined across the spanwise direction due to the action of the plasma discharge. Flow-field measurements show that the opposing plasma discharge causes a mass- and momentum-flux deficit within the boundary layer, leading to a low-velocity region that grows in the streamwise direction and which is characterised by an increase in displacement and momentum thicknesses. This low-velocity ribbon travels downstream, promoting streak-alike patterns of reduction in the convective heat transfer distribution. Near the wall, the plasma-induced jets divert the main flow. This phenomenon is a consequence of the DBD-actuator momentum injection and, thus, the suction caused on the surrounding fluid by the emerging jets. The stationarity of the plasma-induced vortices makes them persistent far downstream, reducing the convective heat transfer.

Computational and Experimental Study of Heat Transfer on the heat sink with an impinging synthetic jet under Various Excitation Wave

This work presents an investigation of an impinging synthetic jet produced by a continuous movement of an oscillating piezoelectric membrane in a synthetic jet actuator (SJA). The jet stream blows from the top of the heat sink attached to an electrically heated mat, and is used to enhance heat transfer to simulate a microelectronic component cooling system. Experimental measurements and numerical simulation were conducted to elucidate the distribution of forced convective heat transfer. The membrane's movement was set to produce a synthetic jet for a complete cycle to investigate flow dynamics in suction and blowing streams. The purpose of this research is to characterize synthetic jet membrane vibrations using sinusoidal, square, and triangular wave excitation modes to find which mode is best for vibrating the synthetic jet membrane. The membrane was excited with various functions, including sinusoidal, triangular, and square waveforms with frequency of 80 Hz, 120 Hz, and 160 Hz. The synthetic jet flow simulation utilized a commercial CFD software, FLUENT and DesignModeler to generate an element meshing with total mesh volume of 537.422. The amplitude for all membrane waves is assumed to be 2 mm/s. A k-ω Shear Stress Transport turbulence model was used to complete the simulation. A user-defined function model was developed to drive the piezoelectric membrane using various sinusoidal and non-sinusoidal excitation waves. Measurements were conducted using thermocouples with an automated data acquisition system to obtain temperature data and derive heat transfer coefficients.The conclusion from this research is that the 120 Hz square wave excitation mode produces the best heat transfer value. This research can contribute to the development of synthetic jet models for the microelectronic component cooling system industry.

Modal decomposition of flow fields and convective heat transfer maps: An application to wall-proximity square ribs

In this work the modal decomposition of convective heat transfer distributions in turbulent flows is explored. The organization and thermal footprint of the turbulent flow features generated downstream of wall-proximity two-dimensional square ribs immersed in a turbulent boundary layer are investigated experimentally. This study employs modal decomposition to investigate whether this analysis can allow identifying which characteristics of the flow topology are responsible for the Nusselt-number augmentation, aiming to uncover the underlying physics of heat-transfer enhancement. Heat transfer and flow velocity measurements are performed at a Reynolds number (based on the free-stream velocity and rib side-length) equal to 4600. Square ribs are tested for two different gap spacings from the wall (0.25 and 0.5 ribs side-length) and in wall-attached configuration. A low-thermal-inertia heat transfer sensor coupled with high-repetition-rate Infrared (IR) thermography is designed to study the unsteady variation of the convective heat-transfer coefficient downstream of the obstacles. Flow-field measurements are performed with non-time-resolved Particle Image Velocimetry (PIV). A modal analysis with Proper Orthogonal Decomposition (POD) is applied to both convective heat-transfer maps and velocity-fields. The comparison of the Nusselt-number spatial modes of the clean turbulent boundary layer configuration and of the configurations with the ribs shows a variation of the spatial pattern associated with oscillations with strong spanwise coherence, opposed to the thin elongated streaks which dominate the convective heat transfer in the clean turbulent boundary layer. In configurations where the convective heat transfer is enhanced by coherent structures located close to the wall, similar eigenspectra are observed for both flow field and convective heat transfer modes. The results of the modal analysis support a picture of a direct relation between the coherence of near-wall flow features and heat-transfer augmentation, providing a statistical evidence for the fact that near-wall coherent eddies are extremely efficient in enhancing heat transfer.

İNDÜKSİYON EŞLENİKLİ ARGON PLAZMASINDA AKIŞ DEBİSİ VE BOBİN LOKASYONUNUN SİSTEM ÇALIŞMA PARAMETRELERİNE ETKİSİ İLE İLGİLİ SİMÜLASYONLAR

The usage areas of the plasmatron has been increasing due to the very high level of temperature which they can reach. They are used widely in the plasma-wind tunnels to create the atmospheric test conditions of high velocity aircrafts and spacecrafts while entering atmosphere. Additionally, most efficient coal and bio-mass burning also, syngas production from burning of the coal and biomass can be achieved with the high temperature plasmatrons. They are also used in the tests of high temperature resistance materials, plasma metallurgy and related scientific researches. The usage of simulation is very important to determination and verification for technical requirements of a plasma and plasmatron system before it’s production, the time, cost and technical risks can be minimized before investing money to the production and development by simulating the related plasma system. In this work, a system that is consisted of inductive coupled plasma (ICP) is investigated by making related computer simulations. Investigated simulations are gas flow simulation, heat transfer simulation and plasma simulation and, these simulations are performed as coupled. In these simulations, the RF frequency is chosen as 13.56 MHz and vacuum pressure is chosen as 1 Torr. This vacuum level is selected appropriately for atmospheric re-entry experimental conditions. The mass flow rate is adjusted as a low and a high level, Q 1 =3 mg/s and Q 2 = 90 mg/s respectively. With these setting the changes of flow, heat and plasma parameters are investigated. Totally, 7 different chemical reaction is added to the realized simulations. The magnetic field distribution, the electric field induced from this magnetic field, the magnetic field magnitude, flow temperature distribution, convective heat transfer distribution, plasma gas velocity field, plasma gas pressure distribution and plasma electron density distribution is calculated in these simulations and, these results are compared for the different gas mass flow rate. Finally, the location of the coils which gives the RF electrical energy to the ICP plasma are slid to where the plasma gas is leaving from the geometry which respect to symmetry axis-z. The simulations are performed when the coils are in the middle and in the gas exit of the geometry. In these two different configurations, the power which this system is taken and mass flow rates are kept the same. These values are 3500 Watt and 90 mg/s respectively. Afterward with the change of the coils location, the plasma electron temperature and plasma gas temperature are investigated for 1-D and 2-D distribution and they are compared for discussion.

Unsteady Aerodynamic Model Based on the Leading-Edge Stagnation Point

The significance of the leading-edge stagnation point as an unsteady aerodynamic observable is investigated. Using first-order unsteady potential flow theory, a simple model relating the stagnation point to the unsteady lift is derived for an airfoil undergoing arbitrary unsteady maneuvers. In particular, the dynamic circulatory effects are shown to be accounted for by tracking the stagnation point. Linearization permits the superposition of solutions for thickness and camber. The model is validated using numerical simulations, employing both steady and unsteady panel methods. In addition, its validity is investigated experimentally through steady and unsteady wind-tunnel tests of a wing section. The stagnation point is estimated in real time from the convective heat transfer distribution measured using a hot-film sensor array instrumented around the wing’s leading edge. Applications of these findings to flutter suppression and gust-load alleviation are experimentally demonstrated.

Flow field features of fractal impinging jets at short nozzle to plate distances

An experimental analysis of the flow field generated by an impinging jet equipped with a fractal grid insert located at the nozzle exit is carried out by means of Tomographic Particle Image Velocimetry. The Reynolds number based on the nozzle exit section diameter d is set to 15,000. The presence of the grid leads to a non uniform curvature of the jet shear layer. As a consequence, azimuthal instabilities are triggered in proximity of the nozzle exit section, causing the production of streamwise vortices. Furthermore, the organization of the coherent structures in proximity of the impinged wall is discussed and related to the convective heat transfer distribution. Owing to the presence of counter rotating wall vortices along the diagonals of the on-plate imprint of the fractal grid, a region of minimum in the scalar transfer map can be detected. In addition to that, similarly to the well known vortex rings that characterize the case of round jet without turbulence promoter, the presence of azimuthally coherent structures that might be generated by Kelvin–Helmholtz instability of the jet shear layer is presented and discussed.

Acoustic resonance excitation of turbulent heat transfer and flow reattachment downstream of a fence

The current work investigates the aero-thermal impact of standing sound waves, excited in a straight channel geometry, on turbulent, separating and reattaching flow over a fence. Effects of distinct frequency resonant forcing (ReH = 10,050 and f = 122 Hz) are quantified by wall static pressure measurements and detailed convective heat transfer distributions via liquid crystal thermometry. Acoustic boundary conditions are numerically predicted and the computed longitudinal resonance mode shapes are experimentally verified by surface microphone measurements. Findings indicate the presence of a resonant sound field to exert strong influence on local heat transfer downstream of the fence, whereas the boundary layer upstream of the obstacle remains notable unaffected. Upstream shift of the maximum heat transfer location and an earlier pressure recovery indicate a reduction in time averaged flow reattachment length of up to 37 %. Although the streamwise peak Nusselt increased by only 5 %, the heat transfer level in the vicinity of the unexcited reattachment zone was locally enhanced up to 25 %. Despite prominent impact of resonant forcing on the fence wake flow, the total pressure drop penalty remained invariant. Observations demonstrate the significant aero-thermal implications of shear layer excitation by standing sound waves superimposed on the channel flow field.

Convective heat transfer investigation of acoustically excited flow over an isolated rib obstacle

The research effort investigates the aero-thermal ramifications of acoustically excited turbulent reattaching shear flow in the wake of an isolated fence obstacle. In order to contrast the effectiveness of traveling and standing sound wave excitations towards surface heat transfer modulation, the flow is stimulated with forcing frequencies and amplitudes, in the ranges of 70–270Hz (St=0.1–0.38) and 103–131dB respectively. Along with local static pressure measurements, the consequent convective heat transfer distributions are quantified by liquid crystal thermometry. Subjected to a standing wave (resonance conditions) within a conductive Strouhal regime in the St=0.17–0.22 range, the separated flow behind the rib is observed to be significantly affected. This is evidenced by size reduction in the time averaged reattachment length of up to 37%. The ensuing local heat transfer enhancement is ∼25%. Conversely, when the flow is excited with acoustic frequencies which do not correspond to resonances (traveling wave forcing), the local heat transfer distributions remained unchanged; however, limited variations in local static pressure are observed. For conditions that yield improved thermal performance, a minimum source amplitude threshold (∼121dB) is found; above this level, the aero-thermal effectiveness of the forcing rises monotonously with increased sound pressure. Even under thermally favorable excitation conditions, the integral pressure drop penalty (total net loss) remains invariant.

Two-Dimensional Heat Transfer Distribution of a Rotating Ribbed Channel at Different Reynolds Numbers

The convective heat transfer distribution in a rib-roughened rotating internal cooling channel was measured for different rotation and Reynolds numbers, representative of engine operating conditions. The test section consisted of a channel of aspect ratio equal to 0.9 with one wall equipped with eight ribs perpendicular to the main flow direction. The pitch to rib height ratio was 10 and the rib blockage was 10%. The test rig was designed to provide a uniform heat flux boundary condition over the ribbed wall, minimizing the heat transfer losses and allowing temperature measurements at significant rotation rates. Steady-state liquid crystal thermography (LCT) was employed to quantify a detailed 2D distribution of the wall temperature, allowing the determination of the convective heat transfer coefficient along the area between the sixth and eighth rib. The channel and all the required instrumentation were mounted on a large rotating disk, providing the same spatial resolution and measurement accuracy as in a stationary rig. The assembly was able to rotate both in clockwise and counterclockwise directions, so that the investigated wall was acting either as leading or trailing side, respectively. The tested Reynolds number values (based on the hydraulic diameter of the channel) were 15,000, 20,000, 30,000, and 40,000. The maximum rotation number values were ranging between 0.12 (Re = 40,000) and 0.30 (Re = 15,000). Turbulence profiles and secondary flows modified by rotation have shown their impact not only on the average value of the heat transfer coefficient but also on its distribution. On the trailing side, the heat transfer distribution flattens as the rotation number increases, while its averaged value increases due to the turbulence enhancement and secondary flows induced by the rotation. On the leading side, the secondary flows counteract the turbulence reduction and the overall heat transfer coefficient exhibits a limited decrease. In the latter case, the secondary flows are responsible for high heat transfer gradients on the investigated area.

Local convective heat transfer identification by infrared thermography from a disc mounted on a cylinder in air crossflow

In this study, the local convective heat transfer from a disc was evaluated using an infrared thermographic experimental set-up. Solving the inverse conduction heat transfer problem allows the local convective heat transfer coefficient to be identified. We used an inverse method, based on spatial regularisation, in order to take radial and azimuthal conduction into account. This model was tested by using a crossflow with a Reynolds number ranging from 11,350 to 39,600, corresponding to the turbulent flow domain. In this paper, the local convective heat transfer distribution on the disc surface allows to study the boundary layer development with upstream Reynolds number as well as the horseshoe vortex and its impact on heat transfer around and downstream of the cylinder.

Frequency response and spatial resolution of a thin foil for heat transfer measurements using infrared thermography

A technique for measuring the spatio-temporal distribution of convective heat transfer has been developed using a test surface fabricated from a thin foil heated electrically. If the heat capacity of the test surface is sufficiently low, the fluctuating temperature on the foil can be measured using high-frame-rate infrared thermography. This method, however, has an inherent problem in that the temperature on the test surface attenuates both in time and space due to thermal inertia and conduction. In the present study, the frequency response and the spatial resolution of a thin foil were examined analytically considering heat losses. In order to derive general relationships, non-dimensional variables of fluctuating frequency and spatial wavenumber were introduced to formulate the temporal and spatial amplitudes of the temperature on the test surface. Based on these relationships, the upper limits on the detectable fluctuating frequency and spatial wavenumber were successfully formulated using governing parameters of the measurement system. This enables us to evaluate quantitatively the reliability of the heat transfer measurement by infrared thermography. The values, evaluated here for the practical conditions, indicated that this measurement technique is promising for investigating the spatio-temporal behavior of heat transfer caused by flow turbulence.