We applied the direct numerical simulation (DNS) to study a principle of drag reduction by attenuating the spanwise fluctuation in near wall region. A simple forcing model was introduced into the Navier-Stokes equation to represent the spanwise drag. Such a drag was applied in particular wave-number space to search the most efficient scale for the operation. The friction drag was effectively reduced when the forcing was given in the wave-number region including streak spacing. However, we could not narrow the range to realize the most effective drag-reduction, because the wall-normal component of turbulence energy grew in the uncontrolled scale. Our result suggested that the manipulation on a particular scale was not effective, but it is necessary to restrain the spanwise fluctuation over a certain spatial scale to achieve the drag-reduction.

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The air-breathing ion engine (ABIE) is a new type of electric propulsion system to be used to compensate the aerodynamic drag of the satellite orbiting at extremely low altitudes. To save the propellant mass for a long operation lifetime, it inhales the low-density atmosphere surrounding the satellite and use it as the propellant of ion engines. Since feasibility and performance of the ABIE depend strongly on the compression ratio and the air-intake efficiency, numerical analysis has been performed by means of the direct-simulation Monte-Carlo method to clarify the characteristics of the air-intake performance in highly rarefied flows. Influences of the flight altitude, the aspect-ratio of the air-intake duct, and the angle of attack are investigated.

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Unsteady behavior of a nematic liquid crystal is simulated by using the Leslie-Ericksen theory as a constitutive equation. After a magnetic field is imposed on nematic flow between parallel plates, the director keeps a symmetric posture with respect to the channel centerline for a certain period, and afterwards, the symmetry is destroyed and the director reorients to the direction parallel to the magnetic field. When the magnetic field intensity is high, the period is short. While pressure gradient at the channel centerline shows the same behavior as that of orientation angle of the director for low magnetic field intensity, it indicates two-stepwise complicated variation before reaching the steady state for high magnetic field intensity. For liquid crystalline flow, pressure depends on the transverse position of a channel. An overshoot phenomenon of pressure near the channel wall is simulated numerically for high magnetic field intensity, which agrees with experimental results.

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This paper describes the application of the optimization procedure for a supersonic wind tunnel two-dimensional variable nozzle contour developed in the previous report to the optimization of a hypersonic wind tunnel axisymmetric nozzle contour of Mach number higher than 5.0. In this procedure, several positions are set on the nozzle wall, and using the linearity of a displacement of each position to the flow pattern, the optimum nozzle contour is determined in a few cases of CFD analyses. To take an axisymmetric nozzle of Mach number 10.0 as an example, optimization was carried out. Mach number deviation in the uniform flow region reduced from 1.48% to 0.40% by the optimization.

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Turbopump inducers often have swirling backflow under a wide range of flow rates because they are designed with a certain angle of attack even at the design point in order to attain high cavitation performance. When the flow rate is decreased, the backflow region extends upstream and may cause various problems by interacting with upstream elements. It is also known that the backflow vortex structure occurs in the shear layer between the main flow and the swirling backflow. In this study, we investigated the backflow vortex structure at the inlet of the inducer by Commputational Fluid Dynamics (CFD). It is difficult to simulate unsteady phenomena such as backflow or backflow vortices by Reynolds Averaged Navier-Stokes Simulation (RANS). For this reason, we applied Large Eddy Simulation (LES) to simulate backflow vortices and to elucidate their fundamental characteristics. It is shown that the results agree reasonably with experiments.

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Large-eddy simulation of compressible transitional flows in a low-pressure turbine cascade is performed by using 6th-order compact difference and 10th-order filtering method. Numerical results without free-stream turbulence and those with about 7% of free-stream turbulence are compared. In these simulations, separated-flows in a turbine cascade accompanied by laminar-turbulent transition are realized, and the present results closely agree with past experimental measurements in terms of the static pressure distribution around the blade. In the case where no free-stream turbulence is taken into account, unsteady pressure field essentially differs from that with strong free-stream turbulence. In the no free-stream turbulence case, pressure waves which propagate from blade's wake region have noticeable effects on the separated-boundary layer near the trailing-edge, and on the neighboring blade.

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Flow induced by plasma synthetic jet actuator (PSJA) is investigated using computational fluid dynamics. PSJA is a flow control device and induces flow using electrohydrodinamic (EHD) effect around electrodes exerted AC voltage. Its mechanism is not well known, but it is said that paraelectric force proportioned to gradient of electric energy density is important on PSJA. In this paper, numerical simulation is documented to discuss mechanism of PSJA with considering only paraelectric force as EHD effect. The numerical results agrees with flow pattern observed on experiments. The difference between two types of PSJA, that is, directed type PSJA and non-directed one is indicated.

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The near pressue field formed around a high speed train causes a vibration problem such as window rattling in the railside residential area. This paper investigates the near pressure field around a train using the potential theory. A train is modeled with the source distribution and the distance attenuation of the pressure field is obtained theoretically. The result shows that the pressure field away from a track only depends on the cross sectional area of a train, and that the pressure variation away from the track can not be weaken by designing the train shape.

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Analysis and model experiment are performed on the compression wave generated by a train entering a tunnel with an entrance hood, which is a prevailing countermeasure to reduce the micro-pressure wave emitted from a Shinkansen tunnel portal. The tunnel entrance hood is a structure to extend a tunnel and has openings at its side walls or roof to decrease the pressure gradient of the compression wave generated by train entry. The hood design has principally been performed through model tests since three-dimensionality of flow field is generally important. Thus, a more efficient design method is required. In this paper, an analytical method based on the aeroacoustic theory developed by Howe is applied to a short “acoustically compact” hood having a window on its side wall. The results are in good agreement with experiments including the train offset effect in a double-tracked tunnel. It is also clarified by the analysis that the performance of the entrance hood is greatly influenced by the relative length of the train nose to the distance between the window and the hood entrance.

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This paper describes an efficient strong coupling method for fluid-structure interaction based on the explicit method for structure and the semi-implicit method for fluid. The solution process of fluid-structure interation system is divided into that of fluid and structure, which is independent to each other except data transfer of the fluid-structure interface. Some existing codes with small modification can be utilized to realize the above two solution processes. Note that the time increment is restricted by the Courant's and diffusive number conditions. The method is applied to solve a loaded cantilever in a flow channel under some conditions. Through the numerical results, characteristics of the method are compared to those of a strong coupling and a weak coupling method

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This paper describes an experimental investigation of the natural transition mechanism of a wake generated behind a thin airfoil in a towing wind tunnel. A linear stability analysis shows that the wake is characterized by a change in the instability from locally absolute to locally convective at a downstream location of the airfoil trailing-edge. When the airfoil is towed in the tunnel, starting vortices are observed first in the wake. The experimental result shows that the feature of startig vortex sustains in the natural transition process due to a self sustained resonance in the absolute unstable region behind the trailing edge. The wake profile in the saturation steady state yields the vortex street structure, where the fluctuation frequency is defined as the fundamental unstable mode by the final saturation steady state. The growth of the fundamental unstable mode in the convectively unstable region suppresses the high frequency fluctuations associated with the staring vortex generation. On the other hand, low-frequency fluctuations in the quasisteady state sustaining in the saturation state grow gradually during the vortex street formation, which lead to the vortex street deformation downstream.

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The flow around a circular cylinder in the uniform flow exposed to a simple and high frequency acoustic excitation as a minute disturbance are studied. In order to clarify the effect of the disturbance on the force exerted by a fluid and to examine its mechanism, mean and fluctuating pressure distributions on the cylinder surface and the velocity field of the cylinder vicinity are carefully investigated. When the periodic disturbance close to the frequency of the transition wave in the separated shear layer is added, the diffusion of the shear layer is promoted or restrained and the fluctuating force associated with the Karman vortex shedding increases or decreases as compared with the case of no excitation.

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A cavitating hydrofoil falls into the self-induced oscillation under some oscillation frequencies and cavitation numbers. Especially, the violent cavitation breakdown occurs periodically while shedding the vortex cavitation when the sheet cavity lengthens near at the trailing edge. It causes the unsteady and nonlinear fluid forces acting on the hydrofoil. This nonlinear phenomenon has not been clarified as yet when the breakdown frequency shedding the vortex cavitation locks in the pitching frequency of the cavitating hydrofoil. The experiment was carried out for a pitching and cavitating NACA hydrofoil in the TMIT cavitation tunnel. The pitching lift coefficient was clarified by load cell measurement with the cavity length and the reduced frequency as parameters. Moreover, particle and bubble image processing technique for PIV is applied to this unsteady cavitation flow. Accordingly, the equivalent void fraction, the velocity vector and the vorticity map including the inner cavity are qualitatively and quantitatively visualized under the shedding vortex cavitation lock-in phase.

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Effects of liquid viscosity on the coalescence of a pair of bubbles were experimentally studied by generating nitrogen gas bubbles in a pool filled with silicone oil. We focused on two types of coalescence/bouncing of bubbles, i.e., those between a rising bubble and a free surface, and between a pair of bubbles rising side by side. The former is considered as the extreme case, which is equivalent to coalescence/bouncing between bubbles with finite and infinite diameters. The later is more practical. That is, bubbles were generated simultaneously from a pair of pinholes on a pipe horizontally placed. We studied the viscosity effects on coalescence of bubbles by investigating the behavior of bubbles with both liquid viscosity and bubble diameter as the parameters. Previous studies reported that We number based on approach velocity could predict whether two bubbles would bounce or coalesce in superpurified water. Our experimental results show that the threshold in the case of low viscosity liquid indicates the same order as the one in the case of superpurified water. On the other hand, in the case of a large viscosity liquid, the threshold differs significantly from the one in the superpurified water.

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In order to clarify the gas-liquid two-phase flow characteristics in a plate heat exchanger, gas-liquid two-phase flows in simulated heat exchangers with a single channel placed in a vertical plane were visualized by a neutron radiography method. Adiabatic air-water two-phase flows and R 141 b boiling two-phase flows were visualized, and two-dimensional void fraction distributions were measured from visualized images via some image processing techniques. Moreover, total pressure loss of adiabatic airwater two-phase flows through the test section was measured, and the frictional pressure loss was calculated by using measured results of average void fraction. As a result, it was shown that the phase distributions in heat exchangers were strongly affected by the inlet configuration and the inlet conditions. In the case that the incoming flow was a gas-liquid two-phase flow, stagnant liquid at the test section inlet caused unsymmetrical phase distribution. For high gas volumetric flux, both phases tended to flow straight separately and liquid mixing in the channel with ribs was a little. It was also shows that the average void fractions and the frictional pressure loss of adiabatic air-water two-phase flows in the channel with ribs could be correlated by the drift-flux model and the L-M method, respectively.

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Thermal mixing characteristics in a T-junction area which has different type of 90-degree bend in the upstream area are evaluated in order to clarify the effect of the curvature ratio on the fluid mixing and wall-temperature fluctuation. The fluid mixing states at some velocity ratios are visualized with PIV measuring system first and its characteristics are associated with the temperature fluctuation data in the vicinity of wall measured with thin thermocouples. It is clarified that the curvature ratio of 90-degree bend strongly affects the thermofluid mixing state, and different effects on the temperature fluctuation depending on the curvature ratio are confirmed. Especially, there is a possibility that the low curvature ratio of bend, in which a separation occurs, is useful for the control of the wall temperature fluctuation due to the strong turbulent mixing effect

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A water experiment for thermal hydraulics in a mixing tee was performed to investigate thermal striping phenomena. Flow visualization, detailed temperature measurement using a movable thermocouple tree, and measurement of flow velocity using particle image velocimetry were carried out. The flow patterns of jet exiting from the branch pipe could be classified into (1) wall jet (2) deflecting jet and (3) impinging jet according to the inflow condition. The parameter experiments showed that the flow patterns could be predicted by a momentum ratio between the two pipes. Temperature fluctation intensity was high along the edge of the jet exiting from the branch pipe. Near the pipe wall, the intensity was high in the wall jet and the impinging jet cases. The velocity measurement showed that, in the wall jet case, the vortices were generated in the wake region behind the branch pipe jet like Karman vortex. This vortex was correlated with prominent frequency of the temperature fluctuation.

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The wave power generating system using the Wells turbine is installed in the breakwater in Sakata port, Japan, and consists of the air chamber, turbine, generator and safety devices. The purposes of this paper are to reveal the characteristics of each component in this system with the experimental data in the real sea, and to evaluate the accuracy of numerical models used in the simulation. The performance of Wells turbine is examined in detail for the unsteady and full-scale condition, comparing the data of the 1/4 scale model with the steady full-scale one. It is found that the performance of the system for the wave can be evaluated accurately with the steady characteristics of the turbine, in the condition that stall does not happen on the rotor. The angle of attack for the stall depends on the wave characteristics such as the magnitude of unsteadiness, requiring many trials to get the stall angle used by the calculations.

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The wave power generating system using the Wells turbine is installed in the breakwater in Sakata port, Japan, and consists of the air chamber, turbine, generator and safety devices. The purposes of this paper are to reveal the characteristics of each component in this system with the experimental data in the real sea, and to evaluate the accuracy of numerical models used in the simulation. As for the motion of water in the air chamber, the eigenfunction expansion method is introduced, and the wave height measured 275 m away from the chamber is employed for the input of the simulation. The error of the simulation for the total system is finally predicted to be less than 20% when the wave comes within the region of about 20 degree deviation angle.

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The purpose of this paper is to gain a greater understanding of the performance of practical wind turbine generating systems with differing output power controllers and controlling means for wind turbine speed. Use of operating wind turbines is practical for investigating the relations of wind speed, output power, and electric parameters including voltage and current under respective power generating conditions. Subjected wind turbines, both equipped with an asynchronous power generator, are located at two sites and are defined as *Wind turbine A and Wind turbine B in this study, respectively. Their performance differences are examined by measuring wind speed and electric parameters. Wind turbine A controls the output power by varying blade angles while a wound-rotor induction geneator controls the turbine speed. Wind turbine B performs output power control by stalling the blades, and a squirrel-cage induction generator with two speeds by change of poles is adopted for the turbine speed control. The study suggests that both wind turbines have a clear linkage between current and output power fluctuations. Comparison of the fluctuations to wind speed fluctuation, although they are triggered primarily by wind speed fluctuation, clearly indicates the specific behaviors inherent to the respective turbine control mechanisms.

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Numerical analysis has been performed for three-dimensional developed turbulent flow in a square duct with rib-roughened walls. Special attention pays for the prediction of turbulent heat transfer with roughened wall. Roughened wall is composed of small ribs which are located periodically on bottom wall of square duct. In order to clarify the influence of rib cross sectional shape on flow and temperature fields, three kinds of ribs, that are square, triangular and elliptical cross section, is examined from the point of heat transfer. In numerical calculation, algebraic Reynolds stress model is selected for flow field in order to predict anisotropic turbulent flow precisely and zero equation model assuming constant Prandtl number is applied for temperature field to make clear whether such simple model is able to evaluate Nusselt number correctly. Periodic boundary condition has been used for this flow to save computational time. Calculated results of temperature field are compared with the experimental data in order to examine the validity of the presented numerical method. As a result of this calculation, it has been found out that the present method could predict temperature contour lines and Nusselt number qualitatively although agreement is certainly not perfect in all detail. Adding to this, turbulent structure is affected by rib cross section shape, although rib height is small compared with side length of square. Especially, elliptical cross section promotes the production of vertical fluctuating velocity and shear stress which leads to generate the secondary flow of the second kind more actively than the other rib shapes. At the same time, calculated results suggest that heat transfer is enhanced by the elliptical cross section.

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The evaporation characteristics of an emulsion droplet of Oil-in-Water (O/W) type have been conducted experimentally. The evaporation time per initial surface area of droplet τ* is used to estimate the evaporation characteristics of different diameter droplets and to compare a water droplet and an emulsion droplet. As the results, τ* of an O/W emulsion droplet is shorter than a water droplet in the Leidenfrost film boiling regime. The four evaporation modes of O/W type emulsion droplets were observed and these depended on the mixing ratio of water and oil G_s and hot surface temperature T_w. Increasing Gs increases the Leidenfrost temperature of the emulsion droplet which is used to die-cast releasing agent. The micro explosion which occurs during the Leidenfrost film boiling were also observed when T_w was higher than 250°C.

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Measurement techniques for turbulence flow by high time resolution have been developed using Ultrasonic Velocity Profiling technique. The signal processing algorithm affects the time resolution whose maximum of a conventional Ultrasonic Velocity Profiler (UVP) based on the pulse-Doppler signal is on the order of 10 ms, which is insufficient for the investigation of turbulence characteristics. We used a cross correlation technique to estimate a time difference between paired echo signals of ultrasound pulses emissions to improve the time resolution of the UVP. This technique is susceptible to noise, so that the frequently signals of velocity information may hardly be detected out of measured signals especially in such as metal pipes. To solve this issue, a novel signal processing technique by combining the pulsed-Doppler and the cross-correlation techniques has been developed, in which the maximum time resolution attained to be less than 500 μ.s and robustness against noise. The deviation of the measured mean velocity between this novel UVP and existing LDV is within 0.1% even in stainless pipe.

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Utilization of gas-hydrates as a gas-storage medium has a possibility of highly economical transport and safety storage of natural gas. Based on the idea, a development of industrial techniques for high-rate formation of gas-hydrates with high gas-storage ratio is required. In order to improve the method to form gas-hydrate mash with high-storage ratio, a new method for monitoring gas-storage ratio map in gas-hydrate mash by magnetic resonance imaging (MRI) was developed. In this study, gas-hydrate mash was formed from HFC-32 and water in the nonmagnetic high-pressure vessel with fine-bubble injection and mixing paddles, and MR images of gas-hydrate mash were obtained using a portable MR microscope. At a same time, fluid motion of a hydrate mash mixed by the paddle was also observed through the vessel with transparence glass-cylinder using optical camera. The spin-lattice relaxation time, T1, and the spin-spin relaxation time, T2, of a uniform mixing hydrate mash were obtained quantitatively as a function of the gas-storage ratio, which is defined as the ratio of the net gas-volume including in a gas-hydrate mash to the water volume in the vessel. It was obtained experimentally that both relaxation times T1 and T2 did not change from the relaxation times of distilled water before gas-hydrate formation. Based on the results, it was shown that a linear relationship is established between the NMR signal intensity from gas-hydrate mash and the gas-storage ratio in it the derived equation agress to the experimental result measured by gas-hydrate mash mixed uniformly by the paddle. Using the equation, the maps of the gas-storage ratio in a hydrate mash can be quantitatively calculated from MR images. This method was applied to the non-uniform measurement of the gas-storage ratio formed in the gas-hydrate mash under non-uniformly mixing condition. The formation mechanism of the gas-hydrate mash with non-uniform ratio was discussed from the obtained maps of gas-storage ratio and the observation of fluid motion using optical method.

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An analysis is presented to predict on the transient thermal behavior regarding the permafrost formation taking account of periodic heating and cooling at the surface. Based on the preceding studies for the frozen-melting behavior of thermally active layer, it is important to understand the thermal structure in the deep underground from a viewpoint of the global climate changes in mid-and long-term perspectives. The numerical calculations are speculated to treat the boundary conditions in deep end and extended for accounting for the geothermal energy as well.

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An experimental study was performed to clarify the flame structure of a burning fuel droplet. Both OH and soot concentration distributions were measured along diametrical line passing through the center of fuel droplet and the front stagnation point of a fuel droplet flame in steady air stream.The laser induced fluorescence and the laser light scattering techniques were applied for the measurement of OH and soot concentration distributions, respectively. An Nd : YAG laser-pumped pulsed dye laser emitting monochromatic radiation at a wavelength of 283.56 nm was used as the light source for these measurements. Fuel employed were n-heptane, n-hexadecane, benzen, methanol and their mixtures. The results showed that the highly sooting region was located deep inside the flame front, and near the flame front was located the maximum of OH concentration. An increase in the relative humidity in the air stream caused the decrease of OH concentration.

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Extinction limits of counterflow CH₄-N₂/O₂-N₂ non-premixed flames were investigated experimentally by manipulating the global flame structure, that is flame location in counterflow, by varying stoichiometric mixture fraction : Z_st, and under fixed stoichiometric adiabatic flame temperature by keeping molar stoichiometry : M_st constant. Furthermore, the effects of two fluid dynamical fluctuations that were oscillated flow at frequency : 20 Hz and perforated plate turbulent flow on the extinction characteristics of the counterflow flames were also examined. As a result, the extinction limits of the laminar flame increase with increase in Z_st. Amount of oxygen in oxidizer flow increases with Z_st and oxygen promotes chain-branching reaction : O₂+H→OH+O. Therefore the laminar flames stability becomes higher with increase in Z_st under the constant adiabatic flame temperature. For the oscillatory flow, the extinction character indicates the similar tendency to the laminar flame, that is, the oscillated flame shows quasi-steady extinction phenomena and the extinction limits always depend on the flow condition of oxidizer even if the flame is located in the fuel side. On the other hands, the perforated plate turbulent flame stability always depends on both the flame location and the streamside with turbulence. The extinction limits of the counterflow turbulent flame are more influenced by the turbulent fluctuation of the flow in which the flame is located than that of the flow without the flame. It is thought to be that the difference for the extinction character between the oscillatory flame and the turbulent flame is due to unsteadiness of the fluctuation in the flow.

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Cellularity of the propagating spherical laminar flames induced by the flame instability was studied for methane and propane-air mixtures at the equivalence ratios from 0.8 to 1.3 and the initial pressure from 0.10 to 0.50 MPa. The Markstein number was employed to quantify the effects of the equivalence ratio and the pressure of the mixture on the cellularity due to the flame instability. The flame was unstable at the large Peclet number. Cracks due to the flame instability were formed on the flame during the propagation. As the flame propagated, cracks increased and then the flame became cellular. The flame divided by the cracks was stabilized by the increase in the flame stretch. The non-dimensional wave number of the instability increased with the flame propagation. This wave number increased with decreasing the equivalence ratio for the methane mixture and with increasing the equivalence ratio for the propane mixture. It increased with increasing the initial pressure at all the equivalence ratios. It increased as the Markstein number decreased.

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Combustion characteristics of the transient hydrogen jet were investigated by the experiments. Bulk quenching was found to occur in the periphery of the jet due to the low fuel concentration. Then the flame propagation into the lean region in the jet was investigated. Hydrogen was injected into the lean hydrogen-air mixture charge around the lower flammability limit of the premixed mixture. The flame generated in the fuel jet propagated into the lean mixture charge region as if it had as “inertia”. Then it was quenched in the premixed mixture charge. The flame seems to be supported by the burned region from its back until the decay of this support. In order to investigate this “flame inertia”, the interactions between the rich flame and the lean mixture were investigated by the numerical simulations of counterflow premixed flame. Reaction rate of the fuel in the lean mixture depended on the opposing gas temperature.

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The combustion process of natural gas in a premixed charged compression ignition (PCCI) engine is analyzed using computational fluid dynamics included in heterogeneity of mixture concentration and temperature with stochastic approach. The non-uniform states of turbulence mixing, ignition process is statistically described using the probability density functions (PDF). The results show that the course of in-cylinder pressure is good agreement with experimental data and the effect of mixture heterogeneity on the ignition delay and the rate of heat release is revealed.

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This paper describes experimental and calculative investigation results aimed to clarify the relationship between thickness of oil film on a cylinder wall and oil consumption rate of internal combustion engines. The oil film thickness and oil consumption rate have been measured at the same time by using 2-dimensional fluorescence method and hydrogen fuel method. By adopting the measured oil film thickness, the evaporative oil rate at the cylinder wall has been calculated and compared with measured oil consumption rate. The results show that the oil film formed by piston ring sliding motion does not achieve immediate cause of oil consumption.

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The effect of pressure atomization with wall impingement on the atomization characteristics was examined in a real scale jet engine burner. The air velocity was set from 41 to 92 m/s, and the liquid injection pressure was from 0.5 to 7.5 MPa. Two laser facilities were used for measuring the droplet size and the velocity. Applying the pressure atomization with wall impingement is effective to reduce the droplet size (Sauter Mean Diameter, SMD) by 1/3.6 to 1/14. There appeared a condition under which SMD was little affected by the air velocity at higher liquid injection pressure. It was also shown that the SMD dependence on the liquid injection pressure was reasonably consistent with that obtained in a basic study on pressure atomization with wall impingement. It was clearly shown that the liquid atomization regime transitioned from air blasting to pressure atomization in the correlation between size and velocity of each droplet.

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A new composition material for metal-hydrogen, which can store hydrogen, has been developed to increase amount of hydrogen absorption. Thermal diffusivity and conductivity for the new composition material are required to design a storage tank with the metal-hydrogen. For the metal-hydrogen called as AB₅, themal diffusivity and conductivity are measured by using a method newly developed based on an inverse solution for one dimensional heat conduction. It reveals that the thermal diffusivity, a, is almost constant value of 4.0×10^-7m/s² in a range of 10 to 30°C and of 0.148 to 0.502 MPa, while the thermal conductivity linearly increases from 1.0 to 3.0W/ (mK) for the different temperature with the pressure and the composition rate.

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