Relevant bibliographies by topics / Heat transfer; Low blade temperatures

Contents

  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers

Academic literature on the topic 'Heat transfer; Low blade temperatures'

Author: Grafiati
Published: 4 June 2021
Last updated: 1 February 2022

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Journal articles on the topic "Heat transfer; Low blade temperatures"

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Wilson, M., R. Pilbrow, and J. M. Owen. "Flow and Heat Transfer in a Preswirl Rotor–Stator System." Journal of Turbomachinery 119, no. 2 (April 1, 1997): 364–73. http://dx.doi.org/10.1115/1.2841120.

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Conditions in the internal-air system of a high-pressure turbine stage are modeled using a rig comprising an outer preswirl chamber separated by a seal from an inner rotor-stator system. Preswirl nozzles in the stator supply the “blade-cooling” air, which leaves the system via holes in the rotor, and disk-cooling air enters at the center of the system and leaves through clearances in the peripheral seals. The experimental rig is instrumented with thermocouples, fluxmeters, pitot tubes, and pressure taps, enabling temperatures, heat fluxes, velocities, and pressures to be measured at a number of radial locations. For rotational Reynolds numbers of Reφ ≃ 1.2 × 106, the swirl ratio and the ratios of disk-cooling and blade-cooling flow rates are chosen to be representative of those found inside gas turbines. Measured radial distributions of velocity, temperature, and Nusselt number are compared with computations obtained from an axisymmetric elliptic solver, featuring a low-Reynolds-number k–ε turbulence model. For the inner rotor-stator system, the computed core temperatures and velocities are in good agreement with measured values, but the Nusselt numbers are underpredicted. For the outer preswirl chamber, it was possible to make comparisons between the measured and computed values for cooling-air temperatures but not for the Nusselt numbers. As expected, the temperature of the blade-cooling air decreases as the inlet swirl ratio increases, but the computed air temperatures are significantly lower than the measured ones. Overall, the results give valuable insight into some of the heat transfer characteristics of this complex system.
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Nikparto, Ali, and Meinhard T. Schobeiri. "Combined numerical and experimental investigations of heat transfer of a highly loaded low-pressure turbine blade under periodic inlet flow condition." Proceedings of the Institution of Mechanical Engineers, Part A: Journal of Power and Energy 232, no. 7 (February 14, 2018): 769–84. http://dx.doi.org/10.1177/0957650918758158.

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This paper experimentally and numerically investigates heat transfer characteristics of a low-pressure turbine blade under steady/unsteady flow conditions. Generally, the low-pressure turbine blades are not exposed to excessive temperatures that require detailed heat transfer predictions. In aircraft engines, they operate at low Re-numbers causing the inception of large separation bubbles on their suction surface. As documented in previous papers, the results of detailed aerodynamic simulations have shown significant discrepancies with experiments. It was the objective of the current investigation to determine the discrepancies between the experimental and numerical heat transfer results. It is shown that small errors in aero-calculation results in large deviations of heat transfer results. The characteristics of the blades mentioned above, make low-pressure turbine blades suitable candidates for evaluating the predictive capability of any numerical method. Documenting the scope of these discrepancies defines the framework of the current paper. The periodic flow inside the gas turbine engine was simulated using the cascade facility at the Turbomachinery Performance and Flow Research Laboratory (TPFL) of Texas A&M University. In this study, the wakes that originate from stator blades were simulated by moving rods. The instrumented blade was covered with a liquid crystal sheet and it was used to measure heat transfer coefficient. Reynolds-averaged Navier–Stokes equations were used for numerical investigation purposes. Measurements and simulations were conducted at three different Reynolds numbers (110,000, 150,000, and 250,000). Furthermore, for unsteady flow condition, reduced frequencies of the incoming wakes were varied. The current paper includes a comprehensive heat transfer assessment of the predictive capability of Reynolds-averaged Navier–Stokes based tools. The effect of the separation bubbles on heat transfer is thoroughly discussed in this paper. Comparisons of the experimental and numerical results detail the differences and identify the sources of error that leads to in accurate calculations in terms of predicting heat transfer calculation results.
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Rodi, W., and G. Scheuerer. "Calculation of Heat Transfer to Convection-Cooled Gas Turbine Blades." Journal of Engineering for Gas Turbines and Power 107, no. 3 (July 1, 1985): 620–27. http://dx.doi.org/10.1115/1.3239781.

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A mathematical model is presented for calculating the external heat transfer coefficients around gas turbine blades. The model is based on a finite-difference procedure for solving the boundary-layer equations which describe the flow and temperature field around the blades. The effects of turbulence are simulated by a low-Reynolds number version of the k-ε turbulence model. This allows calculation of laminar and transitional zones and also the onset of transition. Applications of the calculation method are presented to turbine-blade situations which have recently been investigated experimentally. Predicted and measured heat transfer coefficients are compared and good agreement with the data is observed. This is true especially for the pressure-surface boundary layer which is of a rather complex nature because it remains in a transitional state over the full blade length. The influence of various flow phenomena like laminar-turbulent transition and of the boundary conditions (pressure gradient, free-stream turbulence) on the predicted heat transfer rates is discussed.
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Ling, J., Y. Cao, and W. S. Chang. "Analyses of Radially Rotating High-Temperature Heat Pipes for Turbomachinery Applications." Journal of Engineering for Gas Turbines and Power 121, no. 2 (April 1, 1999): 306–12. http://dx.doi.org/10.1115/1.2817121.

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A set of closed-form solutions for the liquid film distributions in the condenser section of a radially rotating miniature heat pipe and for the vapor temperature drop along the heat pipe length are derived. The heat transfer limitations of the heat pipe are analyzed under turbine blade cooling conditions. Analytical results indicate that the condenser heat transfer limitation normally encountered by low-temperature heat pipes no longer exists for the high-temperature rotating heat pipes that are employed for turbine blade cooling. It is found that the heat pipe diameter, radially rotating speed, and operating temperature are very important to the performance of the heat pipe. Heat transfer limitations may be encountered for an increased heat input and rotating speed, or a decreased hydraulic diameter. Based on the extensive analytical evaluations, it is concluded that the radially rotating miniature heat pipe studied in this paper is feasible for turbine blade cooling applications.
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Sadowski, Tomasz, and Daniel Pietras. "Heat Transfer Process in Jet Turbine Blade with Functionally Graded Thermal Barrier Coating." Solid State Phenomena 254 (August 2016): 170–75. http://dx.doi.org/10.4028/www.scientific.net/ssp.254.170.

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In the jet engine the temperature of exhaust gases should be as high as possible, from the point of view of its efficiency. The value of this temperature is limited by toughness of the turbine blades material. Superalloy Inconel 625, which is commonly used in aerospace industry, indicates 13% less yield point in 800OC than in 25OC. The temperature of exhaust gases can reach 1500OC. The blade material has to be protected due to this fact. The one possibility of turbine blade protection is using of thermal barriers coatings (TBC). The coating has a very low thermal conductivity and therefore it protects against the thermal shock failure of the substrate material. The TBC can be manufactured as: 1) monocrystalline, 2) layered structures (e.g. [1-3]) or 3) as a functionally graded material (e.g. [4-7]). The differences between the properties of blade material and TBC can lead to significant increase of the high shear stresses in the substrate-TBC interface.In this paper numerical analyses of cooled turbine blade with various kinds of functionally graded thermal coatings were performed. The main aim was to find the optimal material properties distribution of the functionally graded TBC to avoid damage initiation and growth between TBC and substrate. In the calculations the effect of temperature on material properties both mechanical and thermal was taken into consideration.
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Camci, C. "An Experimental and Numerical Investigation of Near Cooling Hole Heat Fluxes on a Film-Cooled Turbine Blade." Journal of Turbomachinery 111, no. 1 (January 1, 1989): 63–70. http://dx.doi.org/10.1115/1.3262238.

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Discrete hole film cooling on highly curved surfaces of a gas turbine blade produces very significant wall temperature gradients and wall heat flux variations near downstream and upstream of rows of circular cooling holes. In this study a set of well-defined external heat transfer coefficient distributions in the presence of discrete hole film cooling is presented. Heat transfer coefficients are measured on the suction side of an HP rotor blade profile in a short-duration facility under well-simulated gas turbine flow conditions. The main emphasis of the study is to evaluate the internal heat flux distributions in a detailed way near the cooling holes by using a computational technique. The method uses the measured external heat transfer coefficients as boundary conditions in addition to available internal heat transfer correlations for the internal passages. The study shows the details of the near hole temperature gradients and heat fluxes. The convective heat transfer inside the circular film cooling holes is shown to be very significant even with their relatively small diameter and lengths compared to the chord length. The study also indicates a nonnegligible wall temperature reduction at near upstream of discrete cooling holes. This is explained with the elliptic nature of the internal conduction field of the blade and relatively low coolant temperature levels at the exit of a film cooling hole compared to the mean blade temperature.
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Krishnamoorthy, V., B. R. Pai, and S. P. Sukhatme. "Influence of Upstream Flow Conditions on the Heat Transfer to Nozzle Guide Vanes." Journal of Turbomachinery 110, no. 3 (July 1, 1988): 412–16. http://dx.doi.org/10.1115/1.3262212.

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The influence of a combustor located just upstream of a nozzle guide vane cascade on the heat flux distribution to the nozzle guide vane was experimentally investigated. The surface temperature distribution around the convectively cooled vane of the cascade was obtained by locating the cascade, firstly in a low-turbulence uniform hot gas stream, secondly in a high-turbulence, uniform hot gas stream, and thirdly in a high-turbulence, nonuniform hot gas stream present just downstream of the combustor exit. The results indicate that the increased blade surface temperatures observed for the cascade placed just downstream of the combustor can be accounted for by the prevailing turbulence level measured at cascade inlet in cold-flow conditions and the average gas temperature at the cascade inlet.
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Xie, Gongnan, and Bengt Sundén. "Comparisons of Heat Transfer Enhancement of an Internal Blade Tip with Metal or Insulating Pins." Advances in Applied Mathematics and Mechanics 3, no. 3 (June 2011): 297–309. http://dx.doi.org/10.4208/aamm.10-10s2-03.

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AbstractCooling methods are needed for turbine blade tips to ensure a long durability and safe operation. A common way to cool a tip is to use serpentine passages with 180-deg turn under the blade tip-cap taking advantage of the three-dimensional turning effect and impingement like flow. Improved internal convective cooling is therefore required to increase the blade tip lifetime. In the present study, augmented heat transfer of an internal blade tip with pin-fin arrays has been investigated numerically using a conjugate heat transfer method. The computational domain includes the fluid region and the solid pins as well as the tip regions. Turbulent convective heat transfer between the fluid and pins, and heat conduction within pins and tip are simultaneously computed. The main objective of the present study is to observe the effect of the pin material on heat transfer enhancement of the pin-finned tips. It is found that due to the combination of turning, impingement and pin-fin crossflow, the heat transfer coefficient of a pin-finned tip is a factor of 2.9 higher than that of a smooth tip at the cost of an increased pressure drop by less than 10%. The usage of metal pins can reduce the tip temperature effectively and thereby remove the heat load from the tip. Also, it is found that the tip heat transfer is enhanced even by using insulating pins having low thermal conductivity at low Reynolds numbers. The comparisons of overall performances are also included.
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Dunn, Michael G. "Convective Heat Transfer and Aerodynamics in Axial Flow Turbines." Journal of Turbomachinery 123, no. 4 (February 1, 2001): 637–86. http://dx.doi.org/10.1115/1.1397776.

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The primary focus of this paper is convective heat transfer in axial flow turbines. Research activity involving heat transfer generally separates into two related areas: predictions and measurements. The problems associated with predicting heat transfer are coupled with turbine aerodynamics because proper prediction of vane and blade surface-pressure distribution is essential for predicting the corresponding heat transfer distribution. The experimental community has advanced to the point where time-averaged and time-resolved three-dimensional heat transfer data for the vanes and blades are obtained routinely by those operating full-stage rotating turbines. However, there are relatively few CFD codes capable of generating three-dimensional predictions of the heat transfer distribution, and where these codes have been applied the results suggest that additional work is required. This paper outlines the progression of work done by the heat transfer community over the last several decades as both the measurements and the predictions have improved to current levels. To frame the problem properly, the paper reviews the influence of turbine aerodynamics on heat transfer predictions. This includes a discussion of time-resolved surface-pressure measurements with predictions and the data involved in forcing function measurements. The ability of existing two-dimensional and three-dimensional Navier–Stokes codes to predict the proper trends of the time-averaged and unsteady pressure field for full-stage rotating turbines is demonstrated. Most of the codes do a reasonably good job of predicting the surface-pressure data at vane and blade midspan, but not as well near the hub or the tip region for the blade. In addition, the ability of the codes to predict surface-pressure distribution is significantly better than the corresponding heat transfer distributions. Heat transfer codes are validated against measurements of one type or another. Sometimes the measurements are performed using full rotating rigs, and other times a much simpler geometry is used. In either case, it is important to review the measurement techniques currently used. Heat transfer predictions for engine turbines are very difficult because the boundary conditions are not well known. The conditions at the exit of the combustor are generally not well known and a section of this paper discusses that problem. The majority of the discussion is devoted to external heat transfer with and without cooling, turbulence effects, and internal cooling. As the design community increases the thrust-to-weight ratio and the turbine inlet temperature, there remain many turbine-related heat transfer issues. Included are film cooling modeling, definition of combustor exit conditions, understanding of blade tip distress, definition of hot streak migration, component fatigue, loss mechanisms in the low turbine, and many others. Several suggestions are given herein for research and development areas for which there is potentially high payoff to the industry with relatively small risk.
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Tafti, Danesh K., Long He, and K. Nagendra. "Large eddy simulation for predicting turbulent heat transfer in gas turbines." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 372, no. 2022 (August 13, 2014): 20130322. http://dx.doi.org/10.1098/rsta.2013.0322.

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Blade cooling technology will play a critical role in the next generation of propulsion and power generation gas turbines. Accurate prediction of blade metal temperature can avoid the use of excessive compressed bypass air and allow higher turbine inlet temperature, increasing fuel efficiency and decreasing emissions. Large eddy simulation (LES) has been established to predict heat transfer coefficients with good accuracy under various non-canonical flows, but is still limited to relatively simple geometries and low Reynolds numbers. It is envisioned that the projected increase in computational power combined with a drop in price-to-performance ratio will make system-level simulations using LES in complex blade geometries at engine conditions accessible to the design process in the coming one to two decades. In making this possible, two key challenges are addressed in this paper: working with complex intricate blade geometries and simulating high-Reynolds-number ( Re ) flows. It is proposed to use the immersed boundary method (IBM) combined with LES wall functions. A ribbed duct at Re =20 000 is simulated using the IBM, and a two-pass ribbed duct is simulated at Re =100 000 with and without rotation (rotation number Ro =0.2) using LES with wall functions. The results validate that the IBM is a viable alternative to body-conforming grids and that LES with wall functions reproduces experimental results at a much lower computational cost.
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Dissertations / Theses on the topic "Heat transfer; Low blade temperatures"

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Gillespie, David R. H. "Intricate internal cooling systems for gas turbine blading." Thesis, University of Oxford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.365831.

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Chan, Phillip. "Jet impingement boiling heat transfer at low coiling temperatures." Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/401.

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The production of advanced high strength steels (AHSS) for use in the automotive and construction industries requires complex control of runout table (ROT) cooling. Advanced high strength steels require coiling at temperatures below 500 °C in order to produce a complex multi-phase microstructure. The research described here will investigate the boiling conditions that occur for moving plate experiments when steel is cooled towards low coiling temperatures. Experiments were performed on a pilot-scale ROT located at the University of British Columbia using industrially supplied steel plates. Tests were performed for four different speeds (0.3, 0.6, 1.0 and 1.3 m/s) and three different initial plate temperatures(350, 500 and 600 °C). Each plate was instrumented with thermocouples in order to record the thermal history of the plate. The results show that cooling is more effective at slower speeds within the stagnation zone for surface temperatures over 200 °C. Outside the stagnation zone regardless of speed cooling is primarily governed by air convection and radiation with minor effects from latent heat caused by splashing water. The maximum peak heat flux value increases with decreasing speed and occurs at a surface temperature of approximately 200 °C, regardless of speed. Below a surface temperature of 200 °C, speed has a negligible effect on peak heat flux. The maximum integrated heat flux seems to vary with speed according to a second order polynomial.
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Ozturk, Burak. "Combined effects of Reynolds number, turbulence intensity and periodic unsteady wake flow conditions on boundary layer development and heat transfer of a low pressure turbine blade." [College Station, Tex. : Texas A&M University, 2006. http://hdl.handle.net/1969.1/ETD-TAMU-1150.

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Jaworská, Petra. "Vliv paliva hořáku na přenos tepla v procesních pecích." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2019. http://www.nusl.cz/ntk/nusl-400846.

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This diploma thesis is about an influence of technical gases CO2 and N2, that are present in a fuel, over overall combustion process and a flue gas emissions. The first part of this thesis discussed issues like heat transfer, basic process combustion utilities, used technical gases in experimental part and finally description of observed pollutants. Second part of thesis describes the experiments themselves. Experiments were trying to find how selected parameters were influenced by adding 40 mN3/h or 80 mN3/h of inert gases to a flow of natural gas. Observed parameters were namely emission volumes, flame parameters and maximal heat duty. Experiments took place in horizontal water-cooled combustion chamber and were performed on two different types of burners. Evaluation of results confirmed clear connection of inert gases on temperature of flame; the biggest temperature drop was observed while inert gas CO2 was present in fuel. Lowering of temperature spikes also highly influenced presence of NOx in hot flue gas during all performed trials.
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Pathak, Mihir Gaurang. "Periodic flow physics in porous media of regenerative cryocoolers." Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/49056.

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Pulse tube cryocoolers (PTC) are a class of rugged and high-endurance refrigeration systems that operate without moving parts at their low temperature ends, and are capable of reaching temperatures down to and below 123 K. PTCs are particularly suitable for applications in space, guiding systems, cryosurgery, medicine preservation, superconducting electronics, magnetic resonance imaging, weather observation, and liquefaction of gases. Applications of these cryocoolers span across many industries including defense, aerospace, biomedical, energy, and high tech. Among the challenges facing the PTC research community is the improvement of system efficiency, which is a direct function of the regenerator component performance. A PTC implements the theory of oscillatory compression and expansion of the gas within a closed volume to achieve desired refrigeration. An important deficiency with respect to the state of art models dealing with PTCs is the limited understanding of the hydrodynamic and thermal transport parameters associated with periodic flow of a cryogenic fluid in micro-porous structures. In view of the above, the goals of this investigation include: 1) experimentally measuring and correlating the steady and periodic flow Darcy permeability and Forchheimer’s inertial hydrodynamic parameters for available rare-Earth ErPr regenerator filler; 2) employing a CFD-assisted methodology for the unambiguous quantification of the Darcy permeability and Forchheimer’s inertial hydrodynamic parameters, based on experimentally measured steady and periodic flow pressure drops in porous structures representing recently developed regenerator fillers; and 3) performing a direct numerical pore-level investigation for steady and periodic flows in a generic porous medium in order to elucidate the flow and transport processes, and quantify the solid-fluid hydrodynamic and heat transfer parameters. These hydrodynamic resistances parameters were found to be significantly different for steady and oscillatory flows.
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Park, Chang Yong. "Carbon dioxide and R410A flow boiling heat transfer, pressure drop, and flow pattern in horizontal tubes at low temperatures /." 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3250306.

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Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2006.
Source: Dissertation Abstracts International, Volume: 68-02, Section: B, page: 1263. Adviser: Predrag S. Hrnjak. Includes bibliographical references (leaves 172-179) Available on microfilm from Pro Quest Information and Learning.
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Books on the topic "Heat transfer; Low blade temperatures"

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Frost, Walter. Heat Transfer at Low Temperatures. Springer, 2013.

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Book chapters on the topic "Heat transfer; Low blade temperatures"

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Islam, M. S., D. J. Richards, and R. G. Scurlock. "Enhanced Natural Convective Heat Transfer in a Nitrogen Vapour Column at Low Temperatures." In Advances in Cryogenic Engineering, 1787–95. Boston, MA: Springer US, 1994. http://dx.doi.org/10.1007/978-1-4615-2522-6_218.

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Maheu, N., V. Moureau, and P. Domingo. "Large-Eddy Simulation of Flow and Heat Transfer Around a Low-Mach Number Turbine Blade." In Direct and Large-Eddy Simulation IX, 361–66. Cham: Springer International Publishing, 2015. http://dx.doi.org/10.1007/978-3-319-14448-1_45.

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Ekin, Jack W. "Heat Transfer at Cryogenic Temperatures." In Experimental Techniques for Low-Temperature Measurements, 49–86. Oxford University Press, 2006. http://dx.doi.org/10.1093/acprof:oso/9780198570547.003.0002.

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Diller, Kenneth R. "Modeling of Bioheat Transfer Processes at High and Low Temperatures." In Advances in Heat Transfer, 157–357. Elsevier, 1992. http://dx.doi.org/10.1016/s0065-2717(08)70345-9.

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Vishnu, S. B., and Biju T. Kuzhiveli. "Effect of Roughness Elements on the Evolution of Thermal Stratification in a Cryogenic Propellant Tank." In Low-Temperature Technologies [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.98404.

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The cryogenic propulsion era started with the use of liquid rockets. These rocket engines use propellants in liquid form with reasonably high density, allowing reduced tank size with a high mass ratio. Cryogenic engines are designed for liquid fuels that have to be held in liquid form at cryogenic temperature and gas at normal temperatures. Since propellants are stored at their boiling temperature or subcooled condition, minimal heat infiltration itself causes thermal stratification and self-pressurization. Due to stratification, the state of propellant inside the tank varies, and it is essential to keep the propellant properties in a predefined state for restarting the cryogenic engine after the coast phase. The propellant’s condition at the inlet of the propellant feed system or turbo pump must fall within a narrow range. If the inlet temperature is above the cavitation value, cavitation will likely to happen to result in the probable destruction of the flight vehicle. The present work aims to find an effective method to reduce the stratification phenomenon in a cryogenic storage tank. From previous studies, it is observed that the shape of the inner wall surface of the storage tank plays an essential role in the development of the stratified layer. A CFD model is established to predict the rate of self-pressurization in a liquid hydrogen container. The Volume of Fluid (VOF) method is used to predict the liquid–vapor interface movement, and the Lee phase change model is adopted for evaporation and condensation calculations. A detailed study has been conducted on a cylindrical storage tank with an iso grid and rib structure. The development of the stratified layer in the presence of iso grid and ribs are entirely different. The buoyancy-driven free convection flow over iso grid structure result in velocity and temperature profile that differs significantly from a smooth wall case. The thermal boundary layer was always more significant for iso grid type obstruction, and these obstructions induces streamline deflection and recirculation zones, which enhances heat transfer to bulk liquid. A larger self-pressurization rate is observed for tanks with an iso grid structure. The presence of ribs results in the reduction of upward buoyancy flow near the tank surface, whereas streamline deflection and recirculation zones were also perceptible. As the number of ribs increases, it nullifies the effect of the formation of recirculation zones. Finally, a maximum reduction of 32.89% in the self-pressurization rate is achieved with the incorporation of the rib structure in the tank wall.
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Ortloff, Charles R. "Environmental and Climate Perspectives on New World, Old World, and South-East Asian Societies’ Achievements in the Hydraulic Sciences." In Water Engineering in the Ancient World. Oxford University Press, 2009. http://dx.doi.org/10.1093/oso/9780199239092.003.0008.

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The foregoing chapters detail the many technical innovations in water supply, distribution, and management for several Old World, New World, and South- East Asian societies. For most of the New World’s societies, basic water resource problems evolved around securing their agricultural base given the unique environmental and water resource conditions prevalent in their locations. Diverse New World societies occupying different environment niches from dry coastal margins to wet highlands, often subject to vastly different average temperatures, crop types, and water variation cycles, were shown to devise different approaches to the development of their agricultural bases. While rainfall runoff from mountain watersheds sourced the many rivers of coastal Peruvian valleys and provided the basis for canal irrigation, excessive rainfall and cold in Andean highland locations allowed groundwater-based farming using raised Welds that had thermodynamic advantages based on conservation of the sun’s heat to prevent root crop destruction during freezing nights. The presence of varying climate cycles (excessive rainfall and drought) was seen to influence modifications in coastal canal systems. Alterations in canal size and placement to accommodate reduced-water supplies were evident in intravalley coastal systems where modifications were relatively straightforward in sandy environments. Intervalley water transfers through massive canal systems were a further characteristic of a flexible response to maintain the water resource base and this often involved the transfer of river water from one valley to another depending on agricultural, economic, and political priorities. With increased need for more agricultural lands to meet population demands, increasingly lower slope canals were surveyed to include further downslope lands. Here technical innovation was a key factor in providing surveying expertise to maintain low-slope contour canals. While such canals are found at very early Formative and Preceramic sites, surveying techniques became more refined in time to permit greater use of land areas reachable by low-slope canals. Here both Old and New World societies share their dependence on surveying technology to meet water transfer demands. While Roman surveying favoured the most direct aqueduct routing necessitating long, linear aqueduct structures interspersed with siphons and multitier aqueducts structures where appropriate, New World surveying was different in that canal designs following landscape contours were prevalent and, in some cases, optimized to produce specific and/or maximum flow rate designs. Specific measures to create hydraulic control structures to defend against El Niño destruction are evident in the New World archaeological record indicating an active, innovative engineering response to climate and weather-induced disasters, probably based on the memory of prior destructive events.
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Mark, James E., Harry R. Allcock, and Robert West. "Polysiloxanes and Related Polymers." In Inorganic Polymers. Oxford University Press, 2005. http://dx.doi.org/10.1093/oso/9780195131192.003.0008.

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At the present time, polysiloxanes are unique among inorganic and semi-inorganic polymers. They have been the most studied by far, and are the most important with regard to commercial applications. Thus, it is not surprising that a large number of review articles exist describing the synthesis, properties, and applications of these materials. The Si-O backbone of this class of polymers endows it with a variety of intriguing properties. For example, the strength of this bond gives the siloxane polymers considerable thermal stability, which is very important for their use in high-temperature application (for example as heat-transfer agents and high-performance elastomers). The nature of the bonding and the chemical characteristics of typical side groups give the chains a very low surface free energy and, therefore, highly unusual and desirable surface properties. Not surprising, polysiloxanes are much used, for example, as mold-release agents, for waterproofing garments, and as biomedical materials. Some unusual structural features of the chains give rise to physical properties that are also of considerable scientific interest. For example, the substituted Si atom and the unsubstituted O atom differ greatly in size, giving the chain a very irregular cross section. This influences the way the chains pack in the bulk, amorphous state, which, in turn, gives the chains very unusual equation-of-state properties (such as compressibilities). Also, the bond angles around the O atom are much larger than those around the Si, and this makes the planar all-trans form of the chain approximate a series of closed polygons. As a result, siloxane chains exhibit a number of interesting configurational characteristics. These structural features, and a number of properties and their associated applications, will be discussed in this chapter. The major categories of homopolymers and copolymers to be discussed are linear siloxane polymers [-SiRR'O-] (with various alkyl and aryl R,R' side groups), (ii) sesquisiloxane polymers possibly having a ladder structure, (iii) siloxane-silarylene polymers [-Si(CH3)2OSi(CH3)2(C6H4)m-] (where the skeletal phenylene units are either meta or para), (iv) silalkylene polymers [-Si(CH3)2(CH2)m-], and (v) random and block copolymers, and blends of some of the above. Topics of particular importance are the structure, flexibility, transition temperatures, permeability, and other physical properties.
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"Fig. 14 Scraped-surface anchor agitator with auxiliary crossbar agitator. (From Ref. 20.) have many deleterious effects on it. First, the emulsion may have components that cannot stand the wall temperature, which may be as high as 110-125°C. This is even more important if the dosage has active ingredients that decompose at these temperatures. Second, if the temperature is hot enough, the product may actually stick or burn on the sidewall. Cooling of product through sidewall heat transfer can cause almost as many prob-lems as heating. During cooling, the viscosity of a product almost always increases. A viscous product that is not physically removed from the sidewall builds up and forms an insulating layer than resists efficient heat transfer. Again, once this condition oc-curs, it is very difficult to reverse it. There is a variety of different designs of scraper blades. Some are arranged in rows. Some are offset on either side of the anchor, allowing some overlap as an an-chor makes a complete revolution. Some actually are designed to allow the anchor to revolve in opposite directions, which can prevent the buildup of product on the fol-lowing edge of the anchor. Some designs use a spring to force the blade against the wall. Most modern designs use the force of the liquid flowing into the blade to bring it close to the wall. Scraped-surface agitators are definitely required in emulsification equipment where heat transfers are necessary. These anchor agitators with scraping blades can be just as simple anchors or part of complex multishaft mixers. 5. Counterrotation Anchor-type agitators have a decided weakness when handling high-viscosity products of more than about 75,000-100,000 centipoise. They tend to rotate only the product,." In Pharmaceutical Dosage Forms, 340. CRC Press, 1998. http://dx.doi.org/10.1201/9781420000955-41.

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"Fig. 12 Radial (Rushton) type impeller. blade angle, it is best to work closely with the manufacturers of the mixer to specify an optimum design for the process. The preceding discussion of axial- and radial-flow turbines has been a very cur-sory survey of what can be a very involved and detailed study. As mentioned above, a large amount of research on these types of mixers is available [13,14]. A detailed dis-cussion of this subject would be beyond the scope of this work. If a blending or sus-pension problem occurs in large production batches, consultation of the references on mixing included at the end of this chapter or, even better, consulting the experts at the major manufacturers of this type of mixer, would be the best place to start. 3. Anchor Mixers An often overlooked mixing device, which is low speed and considered low capabil-ity, is the anchor agitator, so named for its anchorlike shape, as illustrated in Fig. 13. However, this slowly moving agitator makes it possible for many dispersion and emul-sification processes to be accomplished without overshear, aeration, and heat transfer problems. The anchor agitator is a slow (up to 50 rpm) device whose sole function is to rotate the contents of a batch in a radial direction without providing any significant shear. These are high-torque devices that must be designed sturdily to withstand the forces of the high viscosities. Anchor agitators are typically designed to be able to withstand a maximum viscosity beyond which they might actually bend or break. That is, the an-chor itself is built of materials strong enough to withstand the drag of the viscous liq-uid as it passes by the mixer. In addition, the motor has to supply the very high torque requirement that arises when the anchor is stirring viscous materials. When designing the mixer it is important not to understate the viscosity. This is especially important if there is a point in the process where the anchor must be stopped. If this happens, in the case of shear thinning materials, the agitator has to start up from rest in a viscosity much higher than that normally occurring during the process. Products exhibiting pseudoplastic or Bingham plastic behavior are very difficult to move when at rest." In Pharmaceutical Dosage Forms, 338–39. CRC Press, 1998. http://dx.doi.org/10.1201/9781420000955-40.

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Conference papers on the topic "Heat transfer; Low blade temperatures"

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Amano, R. S., Krishna Guntur, and Jose Martinez Lucci. "Computational Study of Gas Turbine Blade Cooling Channel." In 2010 14th International Heat Transfer Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/ihtc14-22920.

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It has been a common practice to use cooling passages in gas turbine blade in order to keep the blade temperatures within the operating range. Insufficiently cooled blades are subject to oxidation, to cause creep rupture, and even to cause melting of the material. To design better cooling passages, better understanding of the flow patterns within the complicated flow channels is essential. The interactions between secondary flows and separation lead to very complex flow patterns. To accurately simulate these flows and heat transfer, both refined turbulence models and higher-order numerical schemes are indispensable for turbine designers to improve the cooling performance. Power output and the efficiency of turbine are completely related to gas firing temperature from chamber. The increment of gas firing temperature is limited by the blade material properties. Advancements in the cooling technology resulted in high firing temperatures with acceptable material temperatures. To better design the cooling channels and to improve the heat transfer, many researchers are studying the flow patterns inside the cooling channels both experimentally and computationally. In this paper, the authors present the performance of three turbulence models using TEACH software code in comparison with the experimental values. To test the performance, a square duct with rectangular ribs oriented at 90° and 45° degree and placed at regular intervals. The channel also has bleed holes. The normalized Nusselt number obtained from simulation are validated with that of experiment. The Reynolds number is set at 10,000 for both the simulation and experiment. The interactions between secondary flows and separation lead to very complex flow patterns. To accurately simulate these flows and heat transfer, both refined turbulence models and higher-order numerical schemes are indispensable for turbine designers to improve the cooling performance. The three-dimensional turbulent flows and heat transfer are numerically studied by using several different turbulence models, such as non-linear low-Reynolds number k-omega and Reynolds Stress (RSM) models. In k-omega model the cubic terms are included to represent the effects of extra strain-rates such as streamline curvature and three-dimensionality on both turbulence normal and shear stresses. The finite volume difference method incorporated with the higher-order bounded interpolation scheme has been employed in the present study. The outcome of this study will help determine the best suitable turbulence model for future studies.
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Dhiman, Sushant, and Savas Yavuzkurt. "Film Cooling Calculations With an Iterative Conjugate Heat Transfer Approach Using Empirical Heat Transfer Coefficient Corrections." In ASME Turbo Expo 2010: Power for Land, Sea, and Air. ASMEDC, 2010. http://dx.doi.org/10.1115/gt2010-22958.

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An iterative conjugate heat transfer technique has been developed to predict the temperatures on film cooled surfaces such as flat plates and turbine blades. Conventional approaches using a constant wall temperature to calculate heat transfer coefficient and applying it to solid as a boundary condition can result in errors around 14% in uncooled blade temperatures. This indicates a need for conjugate heat transfer calculation techniques. However, full conjugate calculations also suffer from inability to correctly predict heat transfer coefficients in the near field of film cooling holes and require high computational cost making them impractical for component design in industrial applications. Iterative conjugate heat transfer (ICHT) analysis is a compromise between these two techniques where the external flow convection and internal blade conduction are loosely coupled. The solution obtained from solving one domain is used as boundary condition for the other. This process is iterated until convergence. Flow and heat transfer over a film cooled blade is not solved directly and instead convective heat transfer coefficients resulting from external convection on a similar blade without film cooling and under the same flow conditions are corrected by use of experimental data to incorporate the effect of film cooling in the heat transfer coefficients. The effect of conjugate heat transfer is taken into account by using this iterative technique. Unlike full conjugate heat transfer (CHT) the ICHT analysis doesn’t require solving a large number of linear algebraic equations at once. It uses two separate meshes for external convection and blade conduction and thus problem can be solved in lesser time using less computational resources. A demonstration of this technique using a commercial CFD solver FLUENT is presented for simulations of film cooling on flat plates. Results are presented in form of film cooling heat transfer coefficients and surface temperature distribution which are compared with results obtained from conventional approach. For uncooled surfaces, the deviations were as high as 3.5% between conjugate and conventional technique results for the wall temperature. For film cooling simulations on a flat plate using the ICHT approach showed deviations up to 10% in surface temperature compared to constant wall temperature technique for a high temperature difference case and 3% for a low temperature difference case, since surface temperature is not constant over the surface when conjugate heat transfer is considered. Results show that conjugate heat transfer effect is significant for film cooling flows involving high temperature differences for the current blade materials and application of film cooling correction obtained from experimental data is very useful in obtaining realistic blade temperatures.
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Kenkare, A. S., and T. M. Kilner. "A Low-Cost Undergraduate Test Rig for Heat Transfer in Turbine Blade Cooling." In ASME 1985 International Gas Turbine Conference and Exhibit. American Society of Mechanical Engineers, 1985. http://dx.doi.org/10.1115/85-gt-156.

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Although turbine blade cooling has consistently led to the use of higher turbine inlet temperatures leading to improved cycle efficiencies, very little of this technology has found its way into undergraduate laboratory work. The cost of modern blade heat transfer research rigs virtually rules out the possibility of introducing this topic in undergraduate teaching laboratories of Universities or Polytechnics in the UK operating within tight budgetary constraints. However, the underlying principles of blade cooling heat transfer may be demonstrated quite easily by using inlet temperatures about half those existing in the actual turbine and the paper describes the design and development of a low-cost blade cooling heat transfer rig. Test results obtained on the ‘model’ rig enable an appreciation of the problems encountered in turbine blade cooling to be made and may serve as a basis for the design and development of more complicated blade cooling systems.
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Yan, Xin, Lijie Lei, Jun Li, and Zhenping Feng. "Effect of Bending and Mushrooming Damages on Heat Transfer Characteristic in Labyrinth Seals." In ASME 2013 Turbine Blade Tip Symposium. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/tbts2013-2012.

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Using conjugate heat transfer calculations, the heat transfer in straight-through labyrinth seals with and without rub damages (bending and mushrooming damages) were numerically investigated. Firstly, the numerical methods were carefully validated on the basis of obtained experimental data. At two different sealing clearances and a range of Reynolds numbers, Nu distributions on the seal rotor and stator surfaces for the original design cases were numerically computed and compared to the experimental data. The temperature fields in the fluid and inside the solid domains were obtained to account for the heat transfers between fluid and adjacent solids. Then, a range of bending angles, wear-off ratios and mushrooming radiuses were selected to investigate the influence of rub damages on heat transfer characteristic in the labyrinth seals, and the numerical results were also compared to that of original design cases. The results show that the calculated Nu distributions are in good agreement with the experimental data at a range of Re numbers and different sealing clearances. The turbulence model has pronounced effect on the heat transfer computations for the labyrinth seal. Among the selected eddy viscosity turbulence models, the low-Re k-ω and SST turbulence models show superior accuracy to the standard k-ε and RNG k-ε turbulence models, which over-predict Nu by about 70%. Bending damage reduces Nu on the labyrinth fin whereas enhances heat transfer on the opposite smooth stator. The effect of bending angle on Nu distribution on the seal stator surface is larger than on the rotor surface. The mushrooming damage has pronounced effect on Nu distributions on both rotor and stator surfaces for the labyrinth seal. It shows that Nu distributions on the rotor and stator surfaces decreases with the increase of mushrooming radius, but increases with the increase of wear-off ratio and Re.
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Wheeler, Andrew P. S., Nicholas R. Atkins, and Li He. "Turbine Blade Tip Heat Transfer in Low Speed and High Speed Flows." In ASME Turbo Expo 2009: Power for Land, Sea, and Air. ASMEDC, 2009. http://dx.doi.org/10.1115/gt2009-59404.

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In this paper, high and low speed tip flows are investigated for a high-pressure turbine blade. Previous experimental data are used to validate a CFD code, which is then used to study the tip heat transfer in high and low speed cascades. The results show that at engine representative Mach numbers the tip flow is predominantly transonic. Thus, compared to the low speed tip flow, the heat transfer is affected by reductions in both the heat transfer coefficient and the recovery temperature. The high Mach numbers in the tip region (M>1.5) lead to large local variations in recovery temperature. Significant changes in the heat transfer coefficient are also observed. These are due to changes in the structure of the tip flow at high speed. At high speeds, the pressure side corner separation bubble reattachment occurs through supersonic acceleration which halves the length of the bubble when the tip gap exit Mach number is increased from 0.1 to 1.0. In addition, shock/boundary-layer interactions within the tip gap lead to large changes in the tip boundary-layer thickness. These effects give rise to significant differences in the heat-transfer coefficient within the tip region compared to the low-speed tip flow. Compared to the low speed tip flow, the high speed tip flow is much less dominated by turbulent dissipation and is thus less sensitive to the choice of turbulence model. These results clearly demonstrate that blade tip heat transfer is a strong function of Mach number, an important implication when considering the use of low speed experimental testing and associated CFD validation in engine blade tip design.
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Duchaine, Florent, Nicolas Maheu, Vincent Moureau, Guillaume Balarac, and Stéphane Moreau. "Large-Eddy Simulation and Conjugate Heat Transfer Around a Low-Mach Turbine Blade." In ASME Turbo Expo 2013: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/gt2013-94257.

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Determination of heat loads is a key issue in the design of gas turbines. In order to optimize the cooling, an exact knowledge of the heat flux and temperature distributions on the airfoils surface is necessary. Heat transfer is influenced by various factors, like pressure distribution, wakes, surface curvature, secondary flow effects, surface roughness, free stream turbulence and separation. All these phenomenon are challenges for numerical simulations. Among numerical methods, Large Eddy Simulations (LES) offers new design paths to diminish development costs of turbines through important reductions of the number of experimental tests. In this study, LES is coupled with a thermal solver in order to investigate the flow field and heat transfer around a highly loaded low pressure water-cooled turbine vane at moderate Reynolds number (150 000). The meshing strategy (hybrid grid with layers of prisms at the wall and tetrahedra elsewhere) combined with a high fidelity LES solver gives accurate predictions of the wall heat transfer coefficient for isothermal computations. Mesh convergence underlines the known result that wall-resolved LES requires discretisations for which y+ is of the order of one. The analysis of the flow field gives a comprehensive view of the main flow features responsible of heat transfer, mainly the separation bubble on the suction side that triggers transition to a turbulent boundary layer and the massive separation region on the pressure side. Conjugate heat transfer computation gives access to the temperature distribution in the blade, which is in good agreement with experimental measurements. Finally, given the uncertainty on the coolant water temperature provided by experimentalist, uncertainty quantification allows apprehending the effect of this parameter on the temperature distribution.
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Wilson, Michael, Robert Pilbrow, and J. Michael Owen. "Flow and Heat Transfer in a Pre-Swirl Rotor-Stator System." In ASME 1995 International Gas Turbine and Aeroengine Congress and Exposition. American Society of Mechanical Engineers, 1995. http://dx.doi.org/10.1115/95-gt-239.

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Conditions in the internal-air system of a high-pressure turbine stage are modelled using a rig comprising an outer pre-swirl chamber separated by a seal from an inner rotor-stator system. Pre-swirl nozzles in the stator supply the “blade-cooling” air, which leaves the system via holes in the rotor, and disc-cooling air enters at the centre of the system and leaves through clearances in the peripheral seals. The experimental rig is instrumented with thermocouples, fluxmeters, pitot tubes and pressure taps enabling temperatures, heat fluxes, velocities and pressures to be measured at a number of radial locations. For rotational Reynolds numbers of Reϕ ≃ 1.2 × 106, the swirl ratio and the ratios of disc-cooling and blade-cooling flow rates are chosen to be representative of those found inside gas turbines. Measured radial distributions of velocity, temperature and Nusselt number are compared with computations obtained from an axisymmetric elliptic solver, featuring a low-Reynolds-number k-ε turbulence model. For the inner rotor-stator system, the computed core temperatures and velocities are in good agreement with measured values, but the Nusselt numbers are underpredicted. For the outer pre-swirl chamber, it was possible to make comparisons between the measured and computed values for cooling-air temperatures but not for the Nusselt numbers. As expected, the temperature of the blade-cooling air decreases as the swirl ratio increases, but the computed air temperatures are significantly lower than the measured ones. Overall, the results give valuable insight into some of the heat transfer characteristics of this complex system.
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Giel, Paul W., Ronald S. Bunker, G. James Van Fossen, and Robert J. Boyle. "Heat Transfer Measurements and Predictions on a Power Generation Gas Turbine Blade." In ASME Turbo Expo 2000: Power for Land, Sea, and Air. American Society of Mechanical Engineers, 2000. http://dx.doi.org/10.1115/2000-gt-0209.

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Detailed heat transfer measurements and predictions are given for a power generation turbine rotor with 129 deg of nominal turning and an axial chord of 137 mm. Data were obtained for a set of four exit Reynolds numbers comprised of the design point of 628,000, −20%, +20%, and +40%. Three ideal exit pressure ratios were examined including the design point of 1:378, −10%, and +10%. Inlet incidence angles of 0 deg and ±2 deg were also examined. Measurements were made in a linear cascade with highly three-dimensional blade passage flows that resulted from the high flow turning and thick inlet boundary layers. Inlet turbulence was generated with a blown square bar grid. The purpose of the work is the extension of three-dimensional predictive modeling capability for airfoil external heat transfer to engine specific conditions including blade shape, Reynolds numbers, and Mach numbers. Data were obtained by a steady-state technique using a thin-foil heater wrapped around a low thermal conductivity blade. Surface temperatures were measured using calibrated liquid crystals. The results show the effects of strong secondary vortical flows, laminar-to-turbulent transition, and also show good detail in the stagnation region.
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Wang, Zhenfeng, Peigang Yan, Hongfei Tang, Hongyan Huang, and Wanjin Han. "The Simulation Study of Turbulence Models for Conjugate Heat Transfer Analysis of a High Pressure Air-Cooled Gas Turbine." In 2010 14th International Heat Transfer Conference. ASMEDC, 2010. http://dx.doi.org/10.1115/ihtc14-22088.

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The different turbulence models are adopted to simulate NASA-MarkII high pressure air-cooled gas turbine. The experimental work condition is Run 5411. The paper researches that the effect of different turbulence models for the flow and heat transfer characteristics of turbine. The turbulence models include: the laminar turbulence model, high Reynolds number k-ε turbulence model, low Reynolds number turbulence model (k-ω standard format, k-ω-SST and k-ω-SST-γ-θ) and B-L algebra turbulence model which is adopted by the compiled code. The results show that the different turbulence models can give good flow characteristics results of turbine, but the heat transfer characteristics results are different. Comparing to the experimental results, k-ω-SST-θ-γ turbulence model results are more accurate and can simulate accurately the flow and heat transfer characteristics of turbine with transition flow characteristics. But k-ω-SST-γ-θ turbulence model overestimates the turbulence kinetic energy of blade local region and makes the heat transfer coefficient higher. It causes that local region temperature is higher. The results of B-L algebra turbulence model show that the results of B-L model are accurate besides it has 4% temperature error in the transition region. As to the other turbulence models, the results show that all turbulence models can simulate the temperature distribution on the blade pressure surface except the laminar turbulence model underestimates the heat transfer coefficient of turbulence flow region. On the blade suction surface with transition flow characteristics, high Reynolds number k-ε turbulence model overestimates the heat transfer coefficient and causes the blade surface temperature is high about 90K than the experimental result. Low Reynolds number k-ω standard format and k-ω-SST turbulence models also overestimate the blade surface temperature value. So it can draw a conclusion that the unreasonable choice of turbulence models can cause biggish errors for conjugate heat transfer problem of turbine. The combination of k-ω-SST-γ-θ model and B-L algebra model can get more accurate turbine thermal environment results. In addition, in order to obtain the affect of different turbulence models for gas turbine conjugate heat transfer problem. The different turbulence models are adopted to simulate the different computation mesh domains (First case and Second case). As to each cooling passages, the first case gives the wall heat transfer coefficient of each cooling passages and the second case considers the conjugate heat transfer course between the cooling passages and blade. It can draw a conclusion that the application of heat transfer coefficient on the wall of each cooling passages avoids the accumulative error. So, for the turbine vane geometry models with complex cooling passages or holes, the choice of turbulence models and the analysis of different mesh domains are important. At last, different turbulence characteristic boundary conditions of turbine inner-cooling passages are given and K-ω-SST-γ-θ turbulence model is adopted in order to obtain the effect of turbulence characteristic boundary conditions for the conjugate heat transfer computation results. The results show that the turbulence characteristic boundary conditions of turbine inner-cooling passages have a great effect on the conjugate heat transfer results of high pressure gas turbine.
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Kim, Sung In, Md Hamidur Rahman, and Ibrahim Hassan. "Effect of Turbine Inlet Temperature on Blade Tip Leakage Flow and Heat Transfer." In ASME Turbo Expo 2009: Power for Land, Sea, and Air. ASMEDC, 2009. http://dx.doi.org/10.1115/gt2009-60143.

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One of the most critical gas turbine engine components, rotor blade tip and casing, are exposed to high thermal load. It becomes a significant design challenge to protect the turbine materials from this severe situation. As a result of geometric complexity and experimental limitations, Computational Fluid Dynamics (CFD) tools have been used to predict blade tip leakage flow aerodynamics and heat transfer at typical engine operating conditions. In this paper, the effect of turbine inlet temperature on the tip leakage flow structure and heat transfer has been studied numerically. Uniform low (LTIT: 444 K) and high (HTIT: 800 K) turbine inlet temperature have been considered. The results showed the higher turbine inlet temperature yields the higher velocity and temperature variations in the leakage flow aerodynamics and heat transfer. For a given turbine geometry and on-design operating conditions, the turbine power output can be increased by 1.48 times, when the turbine inlet temperature increases 1.80 times. Whereas the averaged heat fluxes on the casing and the blade tip become 2.71 and 2.82 times larger, respectively. Therefore, about 2.8 times larger cooling capacity is required to keep the same turbine material temperature. Furthermore, the maximum heat flux on the blade tip of high turbine inlet temperature case reaches up to 3.348 times larger than that of LTIT case. The effect of the interaction of stator and rotor on heat transfer features is also explored using unsteady simulations.
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