Top PDF Apparatus and method for transient thermal infrared spectrometry

Apparatus and method for transient thermal infrared spectrometry

Apparatus and method for transient thermal infrared spectrometry

A method and apparatus for enabling analysis of a material (16, 42) by applying a cooling medium (20, 54) to cool a thin surface layer portion of the material and to transiently generate a temperature differential between the thin surface layer portion and the lower portion of the material sufficient to alter the thermal infrared emission spectrum of the material from the black-body thermal infrared emission spectrum of the material. The altered thermal infrared emission spectrum of the material is detected by a spectrometer/detector (28, 50) while the altered thermal infrared emission spectrum is sufficiently free of self-absorption by the material of the emitted infrared radiation. The detection is effected prior to the temperature differential propagating into the lower portion of the material to an extent such that the altered thermal infrared emission spectrum is no longer sufficiently free of self-absorption by the material of emitted infrared radiation, so that the detected altered thermal infrared emission spectrum is indicative of the characteristics relating to the molecular composition of the material.
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Apparatus and method for transient thermal infrared spectrometry of flowable enclosed materials

Apparatus and method for transient thermal infrared spectrometry of flowable enclosed materials

A method and apparatus for enabling analysis of a flowable material enclosed in a transport system having an infrared transparent wall portion. A temperature differential is transiently generated between a thin surface layer portion of the material and a lower or deeper portion of the material sufficient to alter the thermal infrared emission spectrum of the material from the black-body thermal infrared emission spectrum of the material, and the altered thermal infrared emission spectrum is detected through the infrared transparent portion of the transport system while the altered thermal infrared emission spectrum is sufficiently free of self- absorption by the material of emitted infrared radiation. The detection is effected prior to the temperature differential propagating into the lower or deeper portion of the material to an extent such that the altered thermal infrared emission spectrum is no longer sufficiently free of self-absorption by the material of emitted infrared radiation. By such detection, the detected altered thermal infrared emission spectrum is indicative of characteristics relating to molecular composition of the material.
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Apparatus and method for transient thermal infrared emission spectrometry

Apparatus and method for transient thermal infrared emission spectrometry

A method and apparatus for enabling analysis of a solid material (16, 42) by applying energy from an energy source (20, 70) top a surface region of the solid material sufficient to cause transient heating in a thin surface layer portion of the solid material (16, 42) so as to enable transient thermal emission of infrared radiation from the thin surface layer portion, and by detecting with a spectrometer/detector (28, 58) substantially only the transient thermal emission of infrared radiation from the thin surface layer portion of the solid material. The detected transient thermal emission of infrared radiation is sufficiently free of self-absorption by the solid material of emitted infrared radiation, so as to be indicative of characteristics relating to molecular
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Apparatus and method for on line barkhausen measurement

Apparatus and method for on-line barkhausen measurement

Apparatus and method for measuring the Barkhausen signal of a moving magnetic film, ribbon or fiber wherein first and second stationary electromagnet coils are arranged and separated by a distance, d, along the path of movement of the film, ribbon or fiber. The first and second coils are energized in a manner to generate first and second opposing DC magnetic fields through which the moving film, ribbon or fiber passes along its path of movement. As the film, ribbon or fiber moves through the first and second opposing magnetic fields at a velocity, v, it experiences one complete cycle of magnetization in a period of time equal to d/v. A stationary third signal pick-up coil is disposed between the first and second coils to detect the Barkhausen signal from the moving film, ribbon or fiber. The pick-up coil typically is disposed midway between the first and second coils where the Barkhausen signal will be approximately maximum.
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Apparatus and method for driving an ultrasonic transducer

Apparatus and method for driving an ultrasonic transducer

A method and apparatus for electronically driving an ultrasonic acoustic transducer. The transducer is operable in two modes; in a first mode, the lock-in frequency of the transducer is determined; in a second mode, the lock-in frequency determined in the first mode is used to modulate a tone-burst pulse to drive the transducer in an efficient manner. Operating in the first mode, the lock-in frequency is determined by exciting the transducer with a series of tone bursts, where each tone burst comprises an electronic pulse modulated by a tone of one frequency selected from a range of frequencies, and measuring the response of the transducer to each tone burst. In an alternative embodiment, the excitation of the transducer in the first mode is provided by a signal whose frequency is swept over a range. The response of the transducer is sampled at various times during the sweep. The lock-in frequency is chosen by examining the responses and choosing the frequency which gives the best response. Operating in the second mode, the transducer is driven with an electronic tone burst generated by modulating said an electronic pulse with a tone of the determined lock-in frequency.
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Method and apparatus for measuring electrical conductivity

Method and apparatus for measuring electrical conductivity

A method of measuring electrical conductivity in a material, said method including the steps of: mounting a pair of electrically conducting elements to be in 15 contact with said materia[r]

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Experimental Study on Thermal Conductivity of Teak Wood Dust Reinforced Epoxy Composite Using Lee’s Apparatus Method

Experimental Study on Thermal Conductivity of Teak Wood Dust Reinforced Epoxy Composite Using Lee’s Apparatus Method

Out of the results obtained it may be concluded that the teak wood dust as reinforcing material is an eco-friendly, nontoxic, low cost and easily available material as compared to synthetic fibres. Epoxy as a matrix material has been used in a wide variety of products such as adhesives, casting compounds, body solders and encapsulates. Good chemical resistance, excellent mechanical properties and modification versatility make epoxy attractive while it’s inherent low viscosity and volatility as well as moderate cure temperature allow for production ease. The measured values of effective thermal conductivity are obtained for different volume fractions of teak wood dust fillers. Incorporation of teak wood dust results in reduction of thermal conductivity of composites there by improves its thermal insulation capability From the experiments it is observed that the composite with particle size 150µ at 35.9% volume fraction teak wood dust exhibited lowest thermal conductivity i.e 0.139W/m-K. Therefore the composite with particle size 150µ at 35.9% teak wood dust may be more suitable for insulation applications and coatings. The results of this study indicate that teak wood dust reinforced composites are light in weight, economical as it is easily available and posses a good thermal insulating properties. Hence the newly developed composite materials can be used for applications in automobile interior parts, electronic packages, ceiling
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Method and apparatus for bone sensing

Method and apparatus for bone sensing

The invention discloses an improved bone conduction sensor capable of use within a voice sound transmitting apparatus. The bone conduction sensor is adapted for placement in the external auditory canal of the user in a nonocclusive fashion. The bone conduction sensor has a contoured surface adapted-to fit against a wall of the external auditory canal increasing the surface area contact between the bone conduction sensor and the wall of the external auditory canal. The bone conduction sensor may also be associated with one or more contact sensors adjacent the bone conduction sensor for determining contact between the bone conduction sensor and the wall of the external auditory canal. In addition, the invention provides for the bone sensing element to be separated from the circuit portion of the bone conduction sensor so that the circuitry may be removed to the behind the ear portion of the earpiece.
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Three-dimensional Transient Heat Transfer Characterization of Crossflow Minichannel Heat Exchanger Apparatus

Three-dimensional Transient Heat Transfer Characterization of Crossflow Minichannel Heat Exchanger Apparatus

Since the suspended nanoparticles inside the base fluids are very fine, it has been considered that these nanoparticles may easily be fluidized. Subsequently, in many researches, nanofluids have been treated as a homogenous fluid by ignoring the relative motion between particles and fluid, and assuming the thermal equilibrium between them [266]. In this approach, the conservation equations of nanofluids are assumed to be similar to those of homogenous fluids; however, the effective properties of the nanofluids are applied for thermo-physical properties. Many researchers claimed that this method is simpler compared to the other approaches, needs less time for calculations, and provides relatively close results to the experimental ones. As a result, this method has attracted the attention of many researchers [266]. Mojarrad et al. [267] performed numerical studies using single-phase homogeneous and dispersion models. The authors studied the effect of nanoparticle concentration and Reynolds number on the convective heat transfer coefficient of nanofluids and compared their predictions with experimental results. They claimed that the homogeneous model is underestimated, whereas the dispersion approach provides more precise predictions.
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Soil Near Infrared Composition Detection Apparatus Design

Soil Near Infrared Composition Detection Apparatus Design

We used the northeast black earth as test samples which acquired from field environment. Acquisition depth was 20cm below the surface of earth and the weight of the sample was 2 kg. The sample was spread out for natural air drying in the indoor, grinding into powder after it was dry. Then used 1 mm sieve to filter, each group sample was divided into two seals to save after filtering. One of the seals was for a chemical method being a reference to measure organic matter and the exact value of total nitrogen content, another seal as the establishment of the forecasting model.
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Micro Calcifications Detection for Breast Cancer Diagnosis using Infrared Thermal Imaging Apparatus

Micro Calcifications Detection for Breast Cancer Diagnosis using Infrared Thermal Imaging Apparatus

A major amount of thermal radiation emitted by an object emitted radiation belongs to the thermal infrared range, in a wave length between 7 and 15 mm. Infrared thermography is the technique of producing an image from infrared radiation, otherwise invisible to the human eye. Thermal cameras have sensors that capture the emitted or reflected thermal radiation from the substance. Images generated by these cameras are referred as thermograms where each image pixel corresponds to a digital value, proportional to the amount of received energy. Infrared thermography is a non-invasive (noncontact, non- destructive) imaging method. This makes infrared thermography a widely applicable technique, for fields such as building and electrical installation inspections and in industrial environments but also in biology and medicine.
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The development of thermal conductivity measurement
apparatus

The development of thermal conductivity measurement apparatus

Thermal conductivity is the fundamental material property that is essential for characterizing the heat transfer. The measurement of thermal conductivity includes the measurement of the heat flux and temperature difference. The difficulty of measurement is always associated with heat flux measurement. None of the thermal conductivity measurement instrument has provided in UTHM and this consequently a number of projects that involves measurement of thermal conductivity cannot be carried out. This study aims to design, fabricate and develop a reliable instrument to measure the thermal conductivity. The design of the instrument was the simplified of the Guarded Hot Plate Method but a plate has been changed with block to see the effects of thermal conductivity value. The Guarded Hot Plate Apparatus is the most accurate method used to measure thermal conductivity of engineering applications. In other words, that apparatus is suitable for engineering applications. The level of reliability that based on the accuracy and consistent will be proven by comparing the experimental value with the theoretical value. The decision was made up upon determining the thermal conductivity for aluminium to test the level of reliability of the thermal conductivity measurement instrument. The result of the experiment depicted that still a small difference between the theoretical value and experimental value, but the best part of the instrument is it able to present almost constant temperature value and thermal conductivity value against time. This depicted the exact level of this instrument compared to the existing instrument.
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Realistic texture in simulated thermal infrared imagery

Realistic texture in simulated thermal infrared imagery

Figure 4.15 shows the LWIR results at all of the simulation times. The orig- inal and simulated versions of the same imaging time reside next to each other throughout Figures 4.15a-l. The 5 AM, 11 AM, & 5 PM images were used in the estimation algorithms. Once again, the 4 PM image represents a separate imag- ing time that can be used to test how well we have estimated the physical thermal parameters using the methods described in Chapter 3. Notice that the night-time 5 AM image does not have the same reverse-contrast issue. This is most likely due to a superior gain/bias DC-to-brightness temperature calibration allowing for nearly perfect estimation of thermal parameters. The challenge of this scene is the ‘beetle’. It is a protruding mound on the order of 20’-across with an unknown ele- vation change. Even with the existing registration error, the movement of the shad- ows as the day progresses reveals to the BDOM algorithm how to estimate the pixel azimuth/zenith angles. The lower-temperature shadow regions of the ‘beetle’ ap- pear in the correct geometric areas of the simulated imagery. However, the extent of the shadowed areas is incorrect due to the mis-registration. As with the ‘Dirt Track’ scene in Section 4.2, the DIRSIG TPM methodology clearly outperforms the prior DIRSIG FM approach. The DIRSIG FM approach rapidly breaks down in the presence of elevation changes as scene geometry is not well-represented.
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Infrared Thermal Mapping, Analysis and Interpretation in Biomedicine

Infrared Thermal Mapping, Analysis and Interpretation in Biomedicine

In medicine, clues to the identification of skin/body regions where disease or injury may exist can be provided by the patient him/herself. In Fig. 3a, the patient had complained of pain at the muscles of the thenar eminence. In Fig. 3a, the painful region is identified by an arrow. An adjacent spot measure (SP2) reveals the tem- perature value; one of a number of regions in this thermogram close to the maximum value in the field of view (maximum being 34.4 °C). In Fig. 3b much greater detail is provided by exploring pixel boundaries around the site (arrow). At least three dif- ferent colour coded regions can be identified within which the temperature values are similar. By using computer-aided software, it is possible to distinguish each of these regions as a separate temperature “ boundary ” . Furthermore, the boundaries make the size and shape of each region, having similar temperature values, become evident. In this way, these images have the potential to map areas of skin temperature linked to the anatomical distribution of pain. This method for outlining areas of similar temperature will aid the objective assessment of the size and position of the area of interest because accuracy of diagnosis depends on how well the segmentation of the ROI is performed in a thermogram [18].
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Infrared Thermography of Cavitation Thermal Effects in Water

Infrared Thermography of Cavitation Thermal Effects in Water

Bearing in mind such a specific nature of cavitation, it is clear that an experimental approach on a local level is very difficult and not many experimental methods are available. For all types of cavitation it is also important that it reflects certain conditions of the flow so that the experimental method used does not alter the flow. Therefore, it is understandable that only few experimental data of cavitation thermal effects are available. This applies especially to the temperature measurements [4] and [5]. Some estimations of the influence of the thermal effect were done by comparing cavitation structures, based on visualization and pressure measurements [6] to [8].
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Discovery of a long lived, high amplitude dusty infrared transient

Discovery of a long lived, high amplitude dusty infrared transient

We report the detection of an infrared-selected transient which has lasted at least five years, first identified by a large mid-infrared and optical outburst from a faint X-ray source detected with the Chandra X-ray Observatory. In this paper we rule out several scenarios for the cause of this outburst, including a classical nova, a luminous red nova, AGN flaring, a stellar merger, and intermediate luminosity optical transients, and interpret this transient as the result of a young stellar object (YSO) of at least solar mass accreting material from the remains of the dusty envelope from which it formed, in isolation from either a dense complex of cold gas or massive star formation. This object does not fit neatly into other existing categories of large outbursts of YSOs (FU Orionis types) which may be a result of the object’s mass, age, and environment. It is also possible that this object is a new type of transient unrelated to YSOs.
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Thermal Infrared vs. Active Infrared: A New Technology Begins to be Commercialized

Thermal Infrared vs. Active Infrared: A New Technology Begins to be Commercialized

In conclusion, it appears that we as thermographers need to be cognizant of this new industry and the terminology being used. For the vast majority of us, this information will provide us with some insights into a new technology and may provide us with a solution for a future problem. At the very least, we have become more knowledgeable about the uses of infrared and how it is changing the world we live in.

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Transient thermal analysis of modified emergency container

Transient thermal analysis of modified emergency container

Abstract—Conventional emergency containers used in steel industry are of less capacity and they had to line with refractory lining which is not economical and time killing process and even the material used for the container is replaced by spheroidal graphite iron instead of cast iron. The intension of this paper is to replace the conventional one with modified emergency container and thus to avoid refractories also to increase the capacity and optimized design for easy handling of the device. The proposed one may subjected to enormous thermal loads hence thermal analysis is carried on the container before its construction. We make use of software ANSYS 10.0 to simulate the model. This paper analyses whether the changing emergency container can be fit for the intensity demand or not so that it could provide the important theory gist to the corporation.
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Transient thermal and structural analysis of disc brake

Transient thermal and structural analysis of disc brake

ALMMC has lower density and thermal conductivity higher compared to GCI and it results in a reduction of the weight of 50 to 60% in the braking circuit as well as improves the fuel economy of the vehicle. Because of the production of heat is more in the cars in the race ALMMC with brake disc can not bear these high temperatures so that it is appropriate to use the brakes to the consumption ALMMC in cars and in vehicles of military transport. The rate of heat generation with the speed is less for ALMMC compared to other materials taking into account all the above parameters is ALMMC is good for disk brake of brake when it is appropriate for the load conditions.
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TRANSIENT THERMAL ANALYSIS OF CAR BRAKE ROTOR DISC BY USING ANSYS SOFTWARE THROUGH FEA METHOD

TRANSIENT THERMAL ANALYSIS OF CAR BRAKE ROTOR DISC BY USING ANSYS SOFTWARE THROUGH FEA METHOD

On studying the background of brakes the main purpose of conducting this research work was finalized. The main objective was to propose a conceptual design for a disc brake rotor using exiting material Aluminum Alloy, Titanium Alloy, Gray Cast iron and new material Carbon Fiber, called a modular brake rotor. The efficient working of brake system depends on how the brake behaves at high temperatures. Thus the aim of the research work will be to reduce the thermal deformation in the modular brake rotor

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