Feasibility of the Space Solar Power System (SSPS) is analyzed for an assumed 10MW model with an idealized generator/transmitter unified modules assembled to make a circular satellite with a diameter of 200m. Even under the operating conditions not advantageous for the heat management and under the use of FC-72 with very low latent heat of vaporization, it is possible to integrate heat transfer area required for keeping the weight fraction of vapor flow at 0.8 and preventing the occurrence of dryout before the radiators. Heat transfer in cold plates and heat transport by two-phase flow loops could be improved much more by using water or other organic fluids with a higher value of latent heat.

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Boiling feature on a super-water-repellent surface with contact angle of 152°has been studied. The stable film boiling occurs in very small superheating and there is no nucleate boiling region. The bubbles generated on the surface coalesce into a vapor film without departing from the surface. The stable vapor film exists without heating even in subcooling of 0,5 and 10 K.

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The transition boiling heat transfer was examined through a model analysis. Considering a pseudo liquid-solid contact right after detachment of a bubble from liquid-vapor interface as a result of Rayleigh-Taylor instability, transient heat conduction was analyzed in it three dimensionally. A liquid-solid contact time and area were given by a correlation of the fractions of liquid-solid contact in the present transition boiling experiments : τ_<contact>=0.3Γ_t, A_<wet>=15×15 Γ_a, Γ=Γ_tΓ_a=1.000-0.7771Θ-0.2695Θ^2,where θ=(T_w-T_<CHF>)/(T_<MHF>-T_<CHF>). The prediction by the present model was in agreement with the present experimental data for water.

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Moleular Dynamics (MD) similation was used to investigate the structural and dynamic properties of zeolite as adsorbent of water. The molecular model was made by quantum chemistry calculation. The mean square displacement (MSD) of water molecules indicates that water in zeolite is in the phase between liquid and solid in any hydration state. Two theories were used to analyze the adsorption heat; Langmuir theory, which optimized with MD calculation in low hydration state, and DR (Dubinin-Radshkevich) theory, which optimized with MD calculation in high hydration state. The results showed that both methods expressed the similar adsorption heat of MD in whole hydration state. However, we found from MD that Langmuir adsorption occurred in low hydration, whilst DR adsorption occurred in high hydration.

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This paper presents a study on the performance improvement of the APT (Atmospheric Pressure Turbine) system that has been operated on the Inverted Brayton Cycle. A method of the inlet air cooling in the gas turbine can be available in order to improve the thermal efficiency of APT operating under the negative pressure region. By the intake air humidification, the increase of the rotational speed was observed experimentally.

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The convective heat transfer between a free surface with impinging jet and a solid surface has been studied numerically. The objective of the study is to investigate the effect of surface orientation on heat transfer. The free surface generated by the jet is tracked by the volume-of-fluid method. The gravitational effect is to be taken into account in order to estimate heat transfer coefficient.

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As devices become smaller and slimmer, the heat generated in their LSI circuits becomes larger, and the speed of hard disks and optical disks increases. As a result, the heat sink and cooling fan inside such devices must be made larger, and in addition, higher fan speeds produce more noise. For these reasons, finding a way to overcome the heat generated in digital devices has been a major problem. Accordingly, we have developed a silent liquid-cooling system to overcome this problem. This system is already being employed in laptop PCs, and is now opening up vast new realms for tomorrow's digital devices. Until now, the backside area of the LCD panel of laptop PCs has never been utilized for cooling purposes. But by installing an aluminum alloy radiator panel over the entire back side of the LCD, we have improved the efficiency of the heat radiation while saving space. In this unprecedented challenge of employing a liquid-cooling system on compact digital devices, we have made full use of the latest technology to prevent liquid leakage (a major concern) and improved reliability with virtually maintenance-free operation.

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In solid/liquid/gas interfaces, with gas dissolution, absorption or adsorption phenomena, marangoni convection which is resulted from concentration difference and temperature difference is expressed. External force such as liquid frequency, micro gravity is operating in this region, a meniscus of edge becomes a thin film and, it is observed that intense flow is developed due to a concentration difference. There are various heat and mass transfer processes with marangoni convection. Among those processes, in this report, our purpose is to clarity phenomena which is to cleaning and drying semiconductors on manufacturing process.

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Numerical calculation of submicron silicon MOSFET and surrounding region is performed. Conjugate nature of the thermal and electrical behavior in the device is considered, and the lattice temperature is solved as well as the electron concentration and the electron temperature. The calculated results show the importance of considering both the electron and lattice temperatures for device modeling; the electron temperature has a significant impact on the calculated electron concentration and the lattice temperature. Furthermore, by extending analysis region, we examine the influence of the computational boundary and the neighboring devices. We discuss the conjugate nature of the thermal and electrical behavior of actual silicon devices for modeling.

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A numerical technique for optimizing the thermal design of power semiconductor modules for mobile communication systems is described. It uses a finite element program for parallel-processing computers to analyze the thermal resistances between the heat-generating layer and the bottom surface of a semiconductor wafer. Since there is a total of more than ten million nodes in the program, it can calculate the temperature distribution inside each heat-generating cell in the semiconductor substrate. The technique was applied to a steady-state analysis to estimate the thermal resistances of collector-up GaAs heterojunction bipolar transistors (HBTs) for small high-power amplifiers used in cellular phones. The results show that the thermal resistances of collector-up HBTs is reduced by 64% of that of normal emitter-up HBTs. They also show that the thermal interface between each collector-up HBT is not negligible even if they are located on a novel thermal via.

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The pin fins is known as having high heat transfer coefficinet, We developed a loop fins with micro-diameter for a water cooling. When the fin pitch along a flow direction was changed, the heat transfer coefficient and pressure drop are experimentally measured to evaluate the performance and effectiveness of the loop fins. As a result, the heat transfer characteristics is veryfied to be predictable by experimental formula of the pin fin and the base plate.

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In a thermal design of compact electronic equipment, the estimation of cooling air flow rate is essential. This paper deals with an experimental study for performance evaluation of cooling fans, in case when obstacles modeling a high-density packing condition are placed around a fan or the inlet of a package is partially closed, aiming to shed a light on the relationship between flow rate and flow condition near intake region of a cooling fan. It is shown that the pressure difference between the front and rear of a fan should be evaluated carefully, when the shape of a flow passage changes abruptly in front of a cooling fan.

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We analyzed various heat loads for the experimental box mounted on the horizontal surface. Furthermore, we developed the numerical prediction method of the heat load on the cubical box which modeled various kinds of container, and we verified this experimentally. This prediction method inputs the thermal characteristic of the box and the environmental data, such as solar radiation, wind velocity, and atmospheric temperature, outputs temperature change of the surface of a wall or an inside of the box. This prediction method can apply them to the analysis of the air conditioning load of a summer.

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This paper describes an experimental study on the influence on the thermal performance of a natural air-cooling heat sink of several conditions as follows; (1) the tilt angle of the base of the one, (2) the gap between the fin tip of the one and an obstacle (or wall), and (3) surrounding air-flow velocity. As a result, the influence of these conditions for the heat sink made of aluminum with the base of 100 mm^H×50 mm^W, and with the fin of 1 mm^t, 25 mm^H and 8.5 mm^P is found.

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High-frequency inductors are one of the most significant loss contributors in switch mode power supply. However, in making the thermal flow simulation model, it is difficult to model a detailed structure of the high-frequency inductor part such as a choke coil and a transformer due to the calculation cost. Therefore, to find the compact modeling method of an inductor part for switch mode power supply, we investigated the effect of proximity losses which occurs close to the air gap, and the effect of anisotropic effective thermal conductivity in inductor windings on the inductor surface temperature. It has been demonstrated in various researches that the proximity-effect losses occurs close to the air gap, and the temperature distribution in an inductor was analyzed in detailed inductor unit. However, in case of system-level thermal analysis, it is not clear how to model the compact thermal model of the inductors which considered the influence of proximity-effect losses on surface temperature.

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This paper presents the experimental results concerning the effects of packaging density to the thermal performance of a PBGA package model mounted on a printed circuit board in a thin compact casing. The casing exit was linked with an exhaust duct, which has an orifice plate for flow measurement in the middle, and an exhaust fan at the end. The thermal resistance values of the package were plotted against the ratio of the obstacle volume to the casing volume and the ratio of obstacle sectional area to the inlet. The results demonstrate that there exist different temperature rise distributions even when both the ratio of the obstacle sectional area to the inlet area and the ratio of the obstacle volume to the casing volume are the same.

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This paper is presented the results of an experimental and numerical study on the effect of the component packaging density to the cooling of natural air-cooled electronic equipment casings. The experiments have been carried out using a ventilated casing with a variety of the volume porosity coefficient in the casing as well as positions of outlet window and heater. The volume porosity coefficient in the casing was varied from 80% to 100% by placing some obstacles, which were assumed as components in the casing. The results show that even if the volume porosity coefficient becomes larger, the mean air temperature rise in the casing hardly changes. The experimental results were compared with the numerical results. The numerical results were very good agreement with experimental ones.

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This paper deals with the analytical and experimental study on rotary total heat exchangers for winter time conditions. Rotary total heat exchangers can also operate in winter time under the same manner as summer time and save the energy of the heating and the humidification during ventilations. The experimental results for some winter time conditions show the increase of humidity efficiency and the decrease of temperature efficiency in the exhaust air side, differing from those numerical results. This tendency is investigated numerically under the consideration of the condensation of moist air. The results show to needs more considerations for the quantitative explanations.

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To clarify the relation between the total heat recovery rate H_<tot, N> of a hybrid type of gas-to-gas heat exchanger and the number of layers N in the heat exchanger, a series of experiments without porous metal plates, as a first step, have been conducted. From the measured results, it is clarified that, compared with bare walls, H_<tot, N> with zigzag fin walls increases to about 2 to 3.5 times for N=2 to 7. However, a rate of increase in H_<tot, N> becomes less steep from N=5 to N=7. Further, measurements of pressure drops in the system with and without zigzag fin walls have been performed for the case of N=7 and the behavior is also discussed.

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Heat and fluid flow characteristics of film flow along vertical grooved channels are investigated as a simple model of plate-type absorber. The film flow is affected by establishing a grooved part on the flat plate. Namely, it is expected that a film thickness becomes thinner at the edge of the groove as the flow deflects into the groove, and consequently fluid mixing is enhanced. In this research, in order to clarify the characteristics between the film flow pattern and heat transfer, we have performed numerical simulations by using Volume of Fluid (VOF) method. In addition, we have also performed experiments with flow visualizations and compared the result with one of numerical simulations.

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We have carried out measurement of velocity and temperature for warm water containing cool immiscible droplets of hydrofluoroether in a vertical transparent duct. The hydrofluoroether has low global warming potential and zero ozone-depletion potential, which is a major advantage when applying to direct-contact heat exchanger. The droplets descend in the water due to the high specific weight. A particle tracking velocimetry method is applied to obtain the velocity field. A planar laser-induced fluorescence method is applied to measure the temperature distribution. It is found that the temperature decreases noticeably in the wake flow region of the descending droplets. This shows that the heat transfer is enhanced by the wake flow.

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This paper describes the flow, heat transfer and pumping power of the mixed convection in a horizontal square duct with heated and cooled side walls by the three-dimensional numerical analysis. The working fluid is water and the temperature dependence of kinetic viscosity and thermal conductivity of water is considered. The SIMPLE procedure and QUICK scheme are used to solve the governing equations through a control volume. Three-dimensional spiral flows are shown along the longitudinal direction of the duct and swirl flows pitch are shortened with increases of Richardson number Ri (=Gr/Re^2). The recirculation flow appears on the upper and bottom wall edge near the starting point of the heat transfer section. The size of the recirculation flow increases with increase of Ri. The pumping power due to swirl flow was also evaluated.

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This report deals with the heat transfer characteristics of exhaust gases condensing in a plate heat exchanger. A model for zeotropic mixtures is modified and applied to the air/steam mixture. In the calculations, the local heat and mass transfer characteristics in the heat exchanger are taken into account. The calculations are carried out varying the temperature, velocity, and air concentration of the exhaust gases at the inlet of the heat exchanger. When the inlet velocity is doubled, the length of the heat exchanger required to satisfy the design specifications increases by 15%. A decrease in the air concentration of 3% increases the required length by 30%. A decrease in the inlet temperature of 50℃ increases the required length by 31%.

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This paper explains about the technological trend and future view of the room air conditioner. As for saving energy, COP value exceeded 5.9 by planning the increase in efficiency of the compressor, the heat exchanger, and the ventilator. Recently, we work for the development to add functions such as not only the room temperature control, which is the original role of the air conditioner, but also the air purity function. As for the future, the development of technology which cope with the diversification of the user's needs, the reduction of energy consumption, and the coexistence with the global environment will become more important.

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Considering ozone depletion and global warming, the conversion from CFC's and HCFC's to alternative/natural refrigerants is an issue of crucial importance. In addition, based on the severe national energy conservation policy, nowadays, all elements of refrigerating and air-conditioning system are subject of research and development. Under these circumstances, and experimental study on condensation is made using V-grooved copper tube and R410A as working refrigerant in this study. Finally, to take into account the heat transfer enhanced effect, the correlation of condensation heat transfer and pressure drop are proposed.

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This paper deals with electricity power consumption (E. P. C.) of refrigerators in residential houses. These days, efficiency of refrigerators is increasing very rapidly and its efficiency is informed by its electricity power consumption value. Each refrigerator has its own E. P. C. value measured by JIS criterion, but it is based on just one particular condition, so that there must be some difference between the E. P. C. value of JIS criterion and actual E.P.C. measured in residential houses. Those differences are studied to show that E. P. C. has a good relation with ambient temperature. In this paper, the relation among E. P. C. ambient temperature, and COP is reported

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Numerical analysis of viscous compressible flow in basic pulse tube refrigerator was performed in order to investigate the wall effect for refrigeration. Transient axisymmetric two-dimensional equations of continuity, momentum and energy were solved utilizing the TVD scheme. Two physical models were used, one is adiabatic wall model in which the heat exchange between the gas and the wall is neglected, and the other is non-adiabatic wall model in which the heat exchange between the gas and the wall is considered as convective heat transfer. In this paper we analyzed the behavior of the change in gas temperature in a steady cyclic state for both models.

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Ball bearings are currently applied to support of screw compressor, but there are serious problems against the action of large load stress by the Hertzian contact. In this paper, the author applies a fluid film bearing focusing on 'spiral-grooved bearing' to the support element of screw compressor because the fluid film bearing can permanently work on the full-film condition. Performances of eight types of spiral-grooved bearing are calculated from the view points of the load-carrying capacity. Finally, the author proposes an application of 'In flow+Radius bearing' to a screw compressor, resulting in an achievement of the long life, high durability against its reverse rotation, and steep cost down.

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This paper aims to estimate the effect of the degree of superheat at compressor inlet on the CO_2 refrigeration cycle's performance and investigate the CO2 Brine-Chiller's COP to control the optimum degree of superheat. Based on the CO2 Brine-Chiller's characteristics, higher degree of superheat decreases refrigerating capacity and COP because the decrease of CO_2 mass flow rate caused by the density decreasing at compressor inlet affects the system performance more than the increase of latent heat at evaporator. According to the CO2 Brine-Chiller's operating data during two years, the degree of superheat at compressor inlet is approximately 20K. Therefore, COP of the CO2 Brine-Chiller will increase to control lower degree of superheat to avoid the CO_2 liquid-compression.

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Carbon dioxide attracts attention as a natural refrigerant, and two-phase ejector is expected to improve the COP (Coefficient of Performance) of carbon dioxide heat pump. This research is aimed to clarify the characteristics of the super sonic two-phase flow of carbon dioxide in a nozzle, which is one of the most important elements of the ejector. In the present study, critical mass flow rate and pressure distribution was measured, and analyzed. While the experimental results of mass flow rate agreed well with the theoretical prediction, the experimental pressure distribution was higher than the theoretical one.

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Carbon dioxide is one of the most hopeful refrigerants because of less emission of greenhouse gases. But when carbon dioxide is used in refrigeration cycle, the energy loss at the expansion valve is increased by three times compared with refrigerants R-134a. This lowers the coefficient of performance. We had been researching the two-phase ejector that recovers this energy to deduce the compressor work. On the other hand, the regeneration is effective for the conventional refrigeration cycle. To elucidate the connection between the two-phase ejector system and the regeneration system, the theoretical research is carried out in this study. The coefficients of performance of the regeneration cycle with conventional expansion valve are shown to be considerably lower than that of the ejector system.

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Hydrocarbon refrigerants such as isobutene are hopeful for the refrigeration cycle, as they exist in a state of nature. But the efficiencies of those cycles must be increased in the standpoint of decreasing the carbon dioxide emissions. We had been researching the two-phase ejector that recovers the energy loss at the expansion to reduce the compressor work. In this report, the coefficients of performance of the two-phase ejector system for the refrigeration cycle using isobutene are estimated by the theory of the ideal ejector. And the results of the system using isobutene are compared with those of R-134a. It is elucidate that the two-phase ejector cycle can be applied to the refrigeration cycle using isobutene as well as that of R-134a. And the increase in the coefficients of performance became large as the temperature of evaporator decrease. At-30 degrees of centigrade about 40% increase in the coefficients of performance is obtained by the ejector cycle.

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In refrigeration and air-conditioning fields, selection of alternative refrigerant of R-22 conventionally used is an important problem. As a new generation refrigerant, hydrofluorocarbons (HFCs), hydrocarbons (HCs), hydrofluoroethers (HFEs), and other substances or the mixtures are compared in this report. As an interface for using refrigerant in industry, thermodynamic equation of state based on thermodynamic-property measurements is needed. Various thermodynamic equations of state are reported for the candidates of new generation refrigerant. In this report, thermodynamic characteristics including COP of the candidates are calculated by using selected equations of state and compared each other from a viewpoint of possibility of a new generation refrigerant.

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Water can be considered as natural refrigerant, which is ideal for sustaining the global environment, though the practical application to refrigerators has been restricted to large scale ice water mixture making for special use. The use of water, due to its large latent heat, is expected to realize a high COP refrigerator, and on the other hand, such refrigerators may become larger than the other types of refrigerator. The present paper describes the characteristics of water as refrigerant, and proposes a unique water-refrigerant based refrigerator with its compactness identical to the conventional ones.

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The practical introduction of a refrigerator using water as natural refrigerant has been prevented by engineering obstacles relating to the high pressure ratio required for its steam compressor. This high pressure ratio requirement, which is typically as high as 10,leads to increased power consumption for compression as well as the adoption of expensive heat-resistant impellers. Although the adoption of conventional indirect heat exchangers for intermediate stage cooling is effective, it is intolerably costly and space occupying. The authors proposed a multi-stage compressor with inter-cooling by direct water injection and atomization, and the results of its performance evaluation is presented here.

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A hybrid air conditioning system consists of a gas engine as a driving source and a hybrid refrigerator that can be driven by waste heat and motive power simultaneously. This paper aims to construct the control systems to drive the hybrid air conditioning system efficiently and clarify the control characteristics by the simulation. In this paper, double effect cycle with waste heat driven solution heat exchanger is adopted for the absorption refrigerator. As a result of the simulation, higher performance part load can be realized by manipulating three parameters-input gas flow rate, the hot water flow rate and solution flow rate-.

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This paper reports some of the problems on downsizing of an ammonia absorption refrigerator and their work-arounds. One of the problems of the downsizing is a solution pump error on starting-up. Focusing solution pump error, authors investigated the cause of the error and conducted experiments on starting-up performance on modifying poor ammonia solution valve characteristic. The experiments of the control system and modification of the control equipment result in restrained the error.

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Sensible/latent heat transfers in a two rotor desiccant cooling process have been experimentally discussed to clarify the effect of water spray evaporative cooler at the inlet of return air stream on the process performance. It was found that the cooling performance was accelerated by the additional evaporative cooler since the enthalpy reduction in the sensible heat exchanger was enhanced by a larger temperature difference between both air streams. This behavior was more realized at higher temperature or lower humidity in the ambient air. On the other hand, a drop in dehumidifying performance due to humidity increase in the regeneration air was compensated by the larger enthalpy reduction in the sensible heat exchanger.

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An advanced-type compact water-tube boiler has been designed on the basis of the new concept of cooling flame by tube-nest in the furnace, and is referred to as tube-nested combustor. It realized drastic reduction in boiler size as well as (NO)_x emission. In a convective heat transfer section downstream the tube-nested combustor, the flow area channel is reduced and the finned tubes are used to increase the heat transfer rate. In this section, heat transfer and flow characteristics are different from the combustion chamber owing to the existence of forward facing step in the flow area. This paper described the result of flow visualization and measurement of heat transfer coefficient in such section.

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Three-dimensional numerical simulation has carried out for a backward-facing step flow in a duct in order to see if intensive difference in flow and thermal structures has been generated for two different inlet velocity conditions between uniform flow and fully-developed flow. Although the maximum Nusselt numbers on the bottom wall appear near the side wall for both cases, the value of it in the fully-developed flow case shows much larger than that in the uniform flow case. Furthermore, owing to the strong complicated three-dimensionality of the flow and thermal structures, Nusselt number for the fully-developed flow especially shows no longer uniform value along the spanwise direction. Fresh downwash fluid near the side wall and its complicated swirl-like motion enhance heat transfer there, whereas, some part of the downwash fluid becomes hot while circulating many times behind the step an flows downstream from the centerline of the duct so that the Nusselt number decreases as it goesfrom the side wall to the duct centerline. It was found that such feature becomes much weaker for the uniform flow case in the present study.

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Large Eddy Simulation (LES) of fully developed flow and heat transfer in a rectangular cooling channel with crossed angled ribs in a gas turbine blade was conducted. The target channel has square-sectional ribs with an angle-of-attack of 60 degrees, which were periodically mounted on the two opposite walls in crossed orientations. Calculations were carried out for three channels that aspect ratios were from 0.5 to 2.0. The numerical results suggest that augmentation of friction and heat transfer varies with the channel aspect ratio. As a result of having derived roughness function for mass and heat transfer from the predicted data, correlations for the friction and heat transfer were reached. The mass transfer correlation agreed well with a previous experiment of a square channel.

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Fluid temperature fluctuation of low frequency, known as the thermal striping phenomena, occurs in the mixing tees of nuclear components with hot and cold fluids. In this study, in order to elucidate the heat transfer characteristic of the thermal striping phenomena, fluid temperature fluctuation is developed by the periodic large scale vortices in a channel flow with rectangular cylinder, and the heat transfer coefficients were measured by the thin film heat flux sensor which was installed in the channel wall. The fluctuations of Nusselt number and fluid temperature are antiphase in the periodic temperature fluctuation field. And the time averaged Nusselt number in the fluid temperature fluctuation field is almost equal to that of the constant fluid temperature, although the R. M. S. of Nusselt number increases with fluid temperature fluctuation.

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A stirred-tank reactor is used as a unit operation in many chemical plants, and is used not only for mixing but also promotion of heating, cooling and reaction. The performance depends on characteristic of vortices formed in a stirred-tank. This investigation was conducted aiming at better understanding of the 3-dimensional structure of vortex flow formed there. The flow visualization and PIV measurement suggested the spiral structure and bifurcation of vortices mainly depending on the liquid height in the tank.

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A study on forced convective heat transfer from a rotating drum with fin array to air is performed to improve the heat removal performance from the ECB retarder. Based on a hypothesis that the heat transfer mechanism consists of the cavity flow over the fin tops and the channel flow passing through the fins, the data obtained in the previous report for the rectangular channel flow, which was made by closing the top side of the channel with aluminum tape, are correlated with taking the similarity with the 'usual' channel flow ito account. Finally a semi-empirical equation of the rectangular channel flow for this system is proposed.

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The spatio-temporal velocity field on the heated rotating disk is measured using ultrasound Doppler velocimetry, respect to the Grashof number and rotating Reynolds number. The measurement component is radial one including a centrifugal force and normal direction one including a buoyancy force. Using the result of velocity field, the analysis is carried out by the correlation of the velocity fluctuation and stochastic method. As a result, the classification between the forced and natural convection in indicated by a unsteady structure. The difference of the traveling velocity of the vortex is clarified by the result of the correlation and conditional average.

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In this report, two &acd; eight vortex generators were inserted in the pipe in order to augment heat transfer. We show how the heat transfer coefficients along the heated pipe are affected by the several longitudinal vortices which were generated by several vortex generators. The streamwise and circumferential heat transfer coefficients in a pipe were measured for air flow over a range of Reynolds number Re ≒1.95&acd;4.75×(10)^4. And, both mean Nusselt number and friction factor were presented as a function of Reynolds number. Moreover, evaluation of the theamal performance ratio was carried out under the condition of fixed pumping power, and it was found that thermal performance ratio of the four type winglet vortex generator is lager than other type of the one.

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Direct numerical simulation and large eddy simulation were performed for a curved channel. In the developed turbulent flow, the spanwise length of the computational domain was changed and behavior of the large-scale vortex was examined. As for the large-scale vortex, it was suggested that negative value of normal velocity can be used as detector of the large scale structure. In the process of the development, thin streamwise structures occur in the computational domain, and, however, these structures grow into large scale vortex.

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An inverse approach to estimate unknown steady thermal boundary conditions with spacewise variation for forced convection field is proposed. The estimation is based on adjoint formulation using transient temperature measurements taken with single sensor. Least squares method is applied to the extimation process to overcome the ill-posed behavior associated with inverse problems. A numerical example determining the unknown wall heaf flux for the parallel plate model is shown to demonstrate the possibility of this method.

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