K-type Thermocouples Research Articles

Design and Implementation of a Temperature Monitoring System in Industrial Environments

Abstract The proposed paper presents the development of a temperature monitoring system designed for industrial environments, based on a Raspberry Pi 3 microcomputer equipped with a touchscreen and a K-type thermocouple connected via the MAX6675 module. The system enables temperature monitoring and recording through an intuitive interface, providing users with real-time visualization and data logging functionalities. The touchscreen interface allows for easy and efficient interaction, enabling operators to quickly access essential information. The system was implemented and tested on an industrial oven capable of reaching temperatures up to 800°C, demonstrating stability and reliability in extreme environmental conditions. Experimental results show that the system provides precise monitoring and enhanced control over high-temperature industrial processes.

Temperature Measurement of Ballistic Evaluation Motor Using K-Type Thermocouple

The paper presents an investigation of the burning rate of the selected solid propellant using a Ballistic Evaluation Motor (BEM) for solid-rocket propulsion study. A K-type thermocouple was used to capture the temperature of the BEM. Previous studies on BEM have been customized to specific experiments accordingly without any standardized approach for temperature measurement. Variations in the methodology have led to inconsistent and potentially unreliable results across different research efforts. The purpose of the study is to establish a more reliable and standardized method for temperature measurement in BEM by validating the temperature readings recorded by a K-type thermocouple. The scope of the study includes recording the ignition and combustion temperature of the BEM against the time. Three different propellants were used in the experiments, ammonium perchlorate with sorbitol and magnesium, potassium nitrate with sucrose, and ammonium perchlorate with sorbitol and iron (III) oxide. The results indicate that ammonium perchlorate with sorbitol gives the highest maximum temperature which is at 101℃. The other propellants, ammonium perchlorate with magnesium and potassium nitrate with sucrose, recorded maximum temperatures of 75.20 °C and 57.25 °C, respectively. The validation process confirmed the reliability of the K-type thermocouple, with an average deviation of 2.3 °C to 3.7 °C from the reference thermometer readings. A notable performance was observed for the propellant using sorbitol andammonium perchlorate with iron (III) oxide. The experiment contributes to significant findings of the solid-rocket propulsion study, hence advanced solidrocket research can be explored from here onwards.

The Effects of Intensity, Exposure Time, and Distance of Polymerization Light on Vickers Microhardness and Temperature Rise of Conventional Resin-Based Composite.

(1) Background: This study investigates the effects of curing light intensity, exposure time, and distance on the Vickers microhardness (VMH), hardness bottom-to-top ratio (HR), and temperature rise (TR) of conventional dental resin-based composite (RBC). (2) Materials and Methods: Specimens of one conventional RBC (Tetric EvoCeram, Ivoclar Vivadent) were cured with 12 different curing protocols (CPs), created with three different light intensities (Quartz Tungsten Halogen 300 mW/cm2, LED 650 mW/cm2, LED 1100 mW/cm2), two exposure times (20 and 40 s), and two distances of curing tip (0 and 8 mm). The VMH of top (VMH-T) and bottom (VMH-B) surfaces was measured. The hardness bottom-to-top ratio (HR) was calculated from VMH-B and VMH-T. The HR below 80% was rated as inadequate polymerization. The TR at the depth of 2 mm within the RBC was measured using a K-type thermocouple. Data were analyzed using Levene's test and the multivariate analysis of variance (MANOVA). The level of significance was set at p < 0.05. (3) Results: Exposure time and distance significantly influenced VMH-B and HR. Increased distance significantly reduced VMH-B, HR, and TR. CPs 300 mW/cm2/8 mm/20 s and 650 mW/cm2/8 mm/20 s produced inadequate polymerization (HR < 80%). Prolonged exposure time produced higher values of VMH-B and HR. The TR was significantly influenced by light intensity and distance. (4) Conclusions: Suboptimal light intensity (<800 mW/cm2) can produce inadequate polymerization at the lower side of the composite layer when used from a distance. Prolonged irradiation can improve the polymerization to a certain extent. Clinicians are advised to monitor the intensity of the LCUs in order to optimize the photopolymerization process. Caution is required when polymerizing with high-intensity curing light in direct contact with the RBC with longer exposure times than recommended.

Polynomial fitting calibration method for K-type thermo-couples based on the least squares method

Abstract Thin-film thermocouples, a crucial technology for accurate temperature measurement, have attracted considerable attention in energy utilization, environmental monitoring, and advanced manufacturing. This paper provides an overview of the evolution of thin-film thermocouples, with a focus on the calibration methods and experimental performance of K-type thermocouples. Utilizing a five-layer film structure that includes a polyimide substrate, aluminum oxide insulation layer, nickel-chromium and nickel-silicon metal films, and a silicon oxide protective layer, we have designed and implemented a new thin-film thermocouple temperature measurement system, which has been experimentally validated for stability and repeatability under high-temperature conditions. The results indicate that the system demonstrates excellent thermoelectric potential output and good repeatability in temperature measurement within the range of 50°C to 250°C. Although the long-term stability in extremely high-temperature environments requires further study, this research provides theoretical and experimental support for the future development of thin-film thermocouple technology.

Physical Heat Cycle Measurement of Resistance Spot Welding

Resistance spot welding (RSW) is still the ideal joining method in the automotive industry. Mostly steel sheets are used in the car body, so overlap and layering are required for welding or riveting, as spot welding provides simultaneous clamping force with interfacial welding to ensure the required strength and quality. A fundamental understanding of heating and cooling rates in thermal distributions is essential for predicting microstructure formation in the weld and the heat-affected zones (HAZ) of RSW joints. The ability to measure the heat cycle in the RSW process can be valuable in weld control and welding parameter optimization. RSW parameters can be optimized through tensile shear tests and microscopic investigations. Heat cycle measurement (HCM) demonstrates the welding consequences in terms of the change in mechanical properties and microstructural formations. The accuracy of cooling rate measurements including t8/5 cooling time is very important to predict the microstructural evolution in the HAZ, however, the thermocouple measurement raises numerous challenges due to the high temperature gradient and small weld and HAZ size. During our investigations heat cycle measurement has been conducted experimentally by a K-type thermocouple. The data logger is connected to the output of the thermocouple for recording the voltage to measure the temperature distributions as a function of both time and position during the welding process. Measurement results of 1 mm thick martensitic MS1400 steel overlapped RSW joints are discussed, and the HCM curve of heating and cooling rates of the spot-welding process is presented. The heat cycle during RSW was measured with two different welding parameter combinations. In addition to welding current, welding time, and electrode force, pulsation has shown disparate curves. Numerous experiments have been attempted to measure the heat cycle in HAZ sub-zones due to the difficulty of positioning the thermocouple accurately, uppercritical HAZ, intercritical HAZ, and subcritical HAZ were investigated and measured in both welding parameter combinations. Difficulties were encountered in the experimental work as a result of the instantaneous welding time and the vibration resulting from the passage of alternating electrical current between the two electrodes. A magnetic field is generated that affects the thermocouple measurement and appears as a noisy curve that is filtered out and smoothed. Joule heat, interfacial heat generation, and cooling effects of electrodes are also considered in the experiment.

Design and evaluation of a gas, temperature profiling and data acquisition system to monitor the performance of a batch fixed dome biogas digester

Recovering energy from biomass and treating organic waste can be done effectively through a biogas digester system. However, monitoring the performance and control of the system to produce biogas is possible through the online process. Therefore, this study developed a novel low-cost gas and temperature profiling system (GTPS) and data acquisition system (DAS) used in biogas digester. The GTPS is designed to monitor and record the amount of methane (CH4) and carbon dioxide (CO2), the main constituent of biogas, from 0 to 100% and to measure the slurry temperature in the digester using a K-type thermocouple. To test the developed monitoring system, the biogas yield (%) and temperature were monitored, and the result obtained agreed with that reported and obtained in the literature (50–70% and 30−40%) for CH4 and CO2, respectively, followed by the desired mesophilic temperature condition for biogas production (20–35 °C). The study employed an RS-232/RS-485 converter for data communication and a low-cost thermocouple module (isolated analog input) that was installed in the data acquisition system. Interestingly, the application of the converter equipment has never been used in any study on monitoring a biogas digester.

Measurement and Analysis of Surface Temperature Gradients on Magnetron Sputtered Thin Film Growth Studied Using NiCr/NiSi Thin Film Thermocouples.

In the general analysis of thin-film growth processes, it is often assumed that the temperature of the film growth surface is the same as the temperature of the film growth substrate. However, a temperature gradient exists between the film growth surface and film growth substrate. Using the growth surface of TiO2 thin films as an example, the temperature gradient of the film growth surface is tested and analyzed. A NiCr/NiSi thin-film thermocouple is fabricated using the direct-current pulse magnetron sputtering method. A three-layer NiCr/NiSi thin-film thermocouple temperature measurement system is established to measure the temperature gradient of the film growth surface. The growth surface temperature and substrate temperature of the TiO2 thin films are measured. For a sputtering power density of 0.83W cm- 2, the temperature difference between the first and second layers is 104.79°C, while the temperature difference between the second and third layers is 39.92°C. A standard K-type thermocouple is used to measure the substrate temperature, which is recorded to be 132.05°C, consistent with common measurements of substrate temperature. The heat conduction on the film growth surface in the vacuum chamber is examined and a model for the temperature measurement device during film growth is constructed.

Investigation of Temperature at Al/Glass Fiber-Reinforced Polymer Interfaces When Drilling Composites of Different Stacking Arrangements

This attempt covers an investigation of cutting temperature at interfaces of Fiber Metal Laminates (FMLs) made of glass fiber-reinforced polymer (GFRP) stacked with an Al2020 alloy. GFRP/Al/GFRP and Al/GFRP/Al composite stacks are both investigated to highlight the effect of stacking arrangement on thermal behavior within the interfaces. In a first test series, temperature history is recorded within the metal/composite stack interfaces using preinstalled thermocouples. In a second test series, a wireless telemetry system connected to K-type thermocouples implanted adjacent to the cutting edge of the solid carbide drill is used to record temperature evolution at the tool tip. Focus is put on the effects of cutting speed and stacking arrangement on the thrust force, drilling temperature, and delamination. From findings, the temperature histories show high sensitivity to the cutting speed. When cutting Al/GFRP/Al, the peak temperature is found to be much higher than that recorded in GFRP/Al/GFRP and exceeds the glass transition point of the GFRP matrix under critical cutting speeds. However, thrust force obtained at constitutive phases exhibits close magnitude when the stacking arrangement varies, regardless of cutting speed. Damage analysis is also discussed through the delamination factor at different stages of FML thickness.

Quantification of core noise using coherent output method: experiment and result on turbofan demonstrator

New turbofan architectures have increasing bypass ratios which makes the core noise an more important source. An identification of its contribution in the total noise has been performed on a DGEN380 turbofan demonstrator using pressure measurement: The remote pressure probes with piezo-electric pressure sensors are installed at 14 locations in the nozzle. The far field noise was caught using 25 microphones array parallel to the engine axis. A coherent output power analysis based on multiple reference channels was applied to identify the active part of the combustion noise and in a reciprocal way the acoustic component in the duct propagated in the test room. The processing allows to calculate the far field contribution and directivity of the core noise. K-type thermocouples were implemented to quantify temperature fluctuations in the engine nozzle. The thermocouples were manufactured with two different wire diameters (from 25 to 80µm) which give different frequency responses. An in-situ compensation method was developed to correct the signal and increase the useful frequency range of the temperature measure. This allows to cover the whole core noise frequency range. This project has received funding from the Clean Sky 2 Joint Undertaking (JU) under grant agreement No. 886554.

Analisis performa inkubator grashof dengan menggunakan lampu LED sebagai pemanas

The high infant mortality rate that occurs between the time after the baby's birth and the time when the baby is not exactly one year old is due to hypothermia/hypertermia, insufficient access to doctors and inability to pay for the use of pre-natal care equipment. Research has been conducted on the analysis of the performance of grashof incubators using LED lamps and copper fiber as heaters to determine the efficiency of LED lights when used for heating in a baby incubator (grazhof inkubator). The results of the research show that 20 watt LED lamp with the addition of fibre as a medium for the heating of air inside incubators is more efficient in tempering the air to reach a temperature of 35oC compared to a 25 watt fiber lamp that does not use a heater fiber. Temperature testing in a baby incubator is measured using a K-type thermocouple due to good accuracy and high sensitivity to temperature changes that need to be monitored in real time. From the results of the analysis of energy efficiency and heating speed (free convection) obtained results that show that with the addition of copper syrup as a heating medium in the incubator has a real influence on the speed of heating air inside the incubators.

Photothermal Effect of 970 nm Diode Laser Irradiation on Enterococcus faecalis Biofilms in Single-Rooted Teeth Ex Vivo.

Objective: The aim of this study was to evaluate the photothermal effect of a 970 nm diode laser on Enterococcus faecalis biofilms. Methods: 72 extracted human single-rooted teeth were prepared, sterilized, and inoculated with Enterococcus faecalis to establish a two-week-old biofilm. The specimens were divided into six groups (n = 12): Group 1 (G1)-negative control (PBS-no laser), Group 2 (G2)-positive control (1% NaOCl rinse-no laser), Group 3 (G3)-a 970 nm laser in 1.5 W pulse mode, Group 4 (G4)-a 970 nm laser in 2 W pulse mode, Group 5 (G5)-a 970 nm laser in 1.5 W continuous mode, Group 6 (G6)-a 970 nm laser in 2 W continuous mode. Bacterial viability was evaluated using the LIVE/DEAD BacLight kit and analyzed by flow cytometry (FCM). Temperature changes on the root surface during irradiation were analyzed using a K-type thermocouple. Data were statistically analyzed using one-way ANOVA and Tukey's multiple comparison test (α = 0.05). Results: Bacterial viability was significantly reduced after laser irradiation in continuous mode using 1.5 W (21% of live bacteria) and 2 W (14% of live bacteria). When the pulsed mode was applied, the reduction in bacterial viability was less, with a mean survival of 53% (1.5 PF, whereas 29% of bacteria survived after 2 W irradiation). Conclusions: The 970 nm diode laser at 2 W continuous mode effectively reduced the viability of E. faecalis biofilms in root canals without causing unacceptable temperature rises at the root surface.

BASE SURFACE TEMPERATURE OF BULK FILL RESIN COMPOSITE WITH DIFFERENT THICKNESS

Background: The material thickness is one factor that influences the polymerization of resin composites. Bulk fill resin composite is an efficient dental resin composite restoration material because it can be cured to a thickness of up to 4-5 mm. The thickness of the material can also affect the temperature rise, while maintaining the temperature is very important because a significant increase can damage the pulp. Purpose: This research aimed to analyze the base surface temperature of bulk fill resin composite with different thicknesses. Methods: Thirty bulk fill resin composite samples with a diameter of 5 mm were divided into three groups with different thicknesses, namely group I (3 mm), group II (4 mm), and group III (5 mm). Each group of samples was cured using an LED Light Curing Unit for 20 seconds, and carried out simultaneously with the measurement of the base surface temperature using a type-K digital thermocouple. Data analyzed using One Way ANOVA and LSD post hoc tests. Results: The mean and standard deviation of the base surface temperature of bulk fill resin composite in groups I, II, and III, respectively, is 37.56 ± 1.06oC, group II 36.89 ± 1.23oC, and group III 36.00 ± 1.2 oC. It showed significantly different between the groups (p&lt;0,05). Conclusion: The thicker the bulk fill resin composite, the lower the base surface temperature.

Combinative effects of thinning and prescribed burning on fuel reduction and soil arthropods: A case study in a Mediterranean pine forest.

Wildfire pressure involves today to implement silvicultural practices that provide a good compromise between reducing fire risk and maintaining ecological functioning. Thinning reduces tree density and low branches, but results in the deposition of a considerable biomass of woody debris on the ground (up to 4800 g m2 in this study). They can be eliminated by prescribed burning, but this raises questions about the fire intensity that can be generated and the impact on soil fauna. We undertook the monitoring of a thinning and prescribed burning operation, separated and combined, in November 2020, in a Pinus laricio stand prone to fire risk, located in Bavella, Corsica. Fuel load was determined, and temperature measurements in the soil were performed using K-type thermocouples. Soil arthropod populations were monitored using pitfall traps, in particular Collembola, Acari, Aranae, and Coleoptera. The combination of thinning and burning resulted in a fire intensity of 75.8 versus 8.4 kW m-1 for burning alone. Maximum temperature rise measured at -2 cm below the surface was less than 5°C for both treatments. The combination of thinning and burning did not result in higher fire intensity at ground level than burning alone, and the soil showed high insulation capacity. Most of the woody debris that burned was small-diameter, and large-diameter debris remained unconsumed. This burning, performed during a period of low biological activity, had no effect on soil arthropods, and the presence of large debris may have provided refuge areas. Collembola group was the faster to recover, and were followed by cohorts of predators in summer, especially Acari. Our results suggest that a combination of burning and thinning in autumn may be beneficial for fire prevention. However, the decomposition of woody debris in relation to fire risk, and the occurrence of pests after these treatments need to be monitored.

Sintering parameter optimization by inverse analysis in direct metal deposition of Inconel 718

PurposeThe net power delivered to the surface of parts (i.e. the actual heat flux) is a key parameter in the laser melting process and its exact control has a great impact on the numerical solutions. In this paper, the impact of laser additive manufacturing parameters including laser power, scanning speed and powder injection rate on thermal efficiency, net power delivered to the part and power loss due to powder flow has been investigated.Design/methodology/approachThe response surface method was applied to measure the net laser power in laser deposited Inconel 718 using k-type thermocouples. The temperature history obtained by thermocouples was used to calculate the net power delivered by inverse analysis method. The applied model is Rosenthal's optimized model, in which all the thermal properties of the material are considered to vary with temperature.FindingsThe results indicated that the thermal efficiency, power delivered to the part and power loss can be optimized simultaneously at laser power of 400 W, scanning speed of 2 mm/s and powder injection rate of 200 mg/s. The microstructure analysis indicated that a high-quality sample without microstructural defects was formed under optimal condition of parameters. Moreover, the primary dendrite arm spacing for the optimal sample was higher than that obtained for other samples.Originality/valueThe novelty of this research summarized as follows: Prediction of the thermal efficiency and power loss during the laser metal deposition of Inconel 718 superalloy using the inverse analysis. Finding the optimal values of thermal efficiency, power delivered to the surface and power loss in the laser metal deposition of Inconel 718 superalloy. Investigating the effect of laser power, powder injection rate and scanning speed on the thermal efficiency and power loss of Inconel 718 superalloy during the laser metal deposition.

Startup characteristics of a water loop heat pipe with dual heat sources for battery thermal management system in electric vehicle

Abstract The usage of electric vehicles has significantly reduced emissions of greenhouse gases and other pollutants. However, the high heat release generated by the electric vehicle batteries poses a challenge. To solve this problem, scientists have created a passive cooling thermal management system specifically for electric vehicle based on heat pipes, particularly loop heat pipes. A battery pack often consists of several battery modules, which results in multiple heat sources being dispersed according to their power capacity. Startup behavior of loop heat pipe has been investigated extensively in the literature. However, most of the studies use only one heat source. This paper aims to fill the research gap, particularly when the system is implemented in dual heat sources managed by only one evaporator. To achieve the research objectives, a custom loop heat pipe was constructed. This cooling system’s design is briefly described. The evaporator is made of copper, deionized water was selected as the working fluid because of its high merit number, which indicates strong performance as a heat pipe working fluid and the stainless-steel wire mesh serves as the porous wick. Battery simulator was built using aluminum material and a cartridge heater to mimic the heat produced by the battery. Two case studies were done. First, only one battery simulator was used. Second, two battery simulators were placed on both sides of the evaporator. A type-K thermocouple attached to the NI DAQ 9214 module was used to measure the temperature while the electric heat load varied between 10 W and 50 W. The study investigated the interaction between the heat load distribution and the startup behavior of the loop heat pipe. Startup behavior is crucial for the performance of the loop heat pipe. Based on the experimental results, the loop heat pipe demonstrates outstanding startup performance. It can effectively initiate operation even at a minimal heat load as low as 30 W for the first and second case study. The findings of the study indicate that the dual heat source arrangement effectively mitigates overshoot temperatures and enhances heat transfer performance by increasing the contact area.

Effect of Shade and Light-Curing Intensity on Bulk-Fill Composite: Heat Generation and Chemo-Mechanical Properties (In Vitro Study)

The aim of this study is to assess the effect of shade and light-curing intensity on the heat generation and degree of conversion of bulk-fill composite. A commercially available bulk-fill composite resin was used in this study. A total of 250 cylindrical specimens of each composite shade (n = 25/group) were prepared (125 for testing heat generation and 125 for testing degree of conversion, then cured using a monowave light-curing unit (LCU) with a single light intensity of 1470 mW/cm2 and a polywave LCU with three different light intensities (1200, 2000, and 3000 mW/cm2). Heat generation during polymerization was measured by five K-type thermocouples placed in each 1 mm layer from top to bottom. FTIR was used for evaluating the degree of conversion. Regarding heat generation, significant differences were seen in layers 4 and 5. Curing types and times also showed significant impacts on heat generation and the degree of conversion. Heat generation relates more to curing time than light intensity. Darker shades generate and retain more heat. Lighter shades exhibit higher degrees of conversion with longer curing.

Impact of Mass Flow Rate on Thermal Behavior of PCM-Based SWH during Charging Operations

Using phase change materials in solar water heaters presents an intriguing prospect due to their notable energy density and potential for substantial thermal energy storage capacity. In the context of active-type solar water heaters, careful consideration must be given to the water flow rate as a crucial parameter. This paper investigates the thermal dynamics of active-type solar water heaters equipped with phase change materials, examining variations in mass flow rate during the charging process. Indoor experiments utilized horizontal tanks, flat plate collectors, pumps, and solar simulators. Cylindrical capsules filled with paraffin wax were employed and arranged horizontally within the tank, while K-type thermocouples were utilized to monitor water and paraffin wax temperatures. Charging procedures were executed over 160 minutes with mass flow rate adjustments. Data analysis was performed to evaluate the system's thermal performance during charging. Results indicate higher mass flow rates correspond to increased instantaneous, cumulative heat storage, and charging efficiency. The mass flow rate notably affects the thermal efficiency of solar water heater systems incorporating phase change materials.

Comparative evaluation of increase in temperature on the external root surface of teeth during retrieval of broken NiTi instrument using two ultrasonic tips and two power settings: An in vitro study.

An unfavorable event that can hinder endodontic treatment and affect the outcome of root canal treatment is the separation of endodontic instruments. Endodontic instrument separation can occur due to clinical or metallurgical factors. Friction between the ultrasonic tip and the remaining dentin generates heat, which is subsequently transferred to the external root surface. Elevated temperatures exceeding 10°C above body temperature for more than a minute may result in injury to periodontal or bone tissue. The aim of this study was to evaluate and compare temperature rise on the external root surface of teeth during retrieval of broken NiTi instrument using two different ultrasonic tips and two power settings. In each group, a sample size of 8 was sufficient to attain a statistical power exceeding 90%, enabling the detection of a minimum mean difference of 0.9204 (delta) through a one-way ANOVA test at a 95% confidence level (alpha 0.05). After access opening and working length determination, samples were randomly distributed into two groups - Group 1 (A and B) - ProUltra tip at high and low power settings and Group 2 (A and B) - Cric Dental IR3 at high and low power settings. The temperature rise was measured using K-type thermocouple thermometer. The comparisons were analyzed using the Kruskal-Wallis test with pairwise comparisons using the Dunn's test. Group 1A and Group 1B resulted in lower heat generation compared to Group 2A and 2B and its difference was statistically significant (P < 0.05). Minimum temperature rise is seen in the ProUltra group at lower power settings (Group 1A) at the apical level and maximum temperature rise is seen in the Cric Dental IR3 group at higher power settings (Group 2B) at the middle third level. It was found that there is a significant temperature rise seen when ultrasonic tips are used for the retrieval of separated files, especially at higher power settings. The ProUltra tip demonstrated the lowest temperature rise at lower power settings, particularly at the apical level, whereas the IR3 Cric Dental tip exhibited the highest temperature rise, notably at higher power settings and the middle third level.

Oil and Gas Pipeline Integrity Monitoring and Alert System

The oil and gas industry face significant risks of explosions, often due to factors like gas and oil leakage as well as external corrosion. These substances are highly flammable, and even minor leaks can create volatile environments where the smallest spark can lead to catastrophic explosions. While internal corrosion in pipelines receives attention, external corrosion is often overlooked. Over time, pipeline coatings deteriorate, leaving them susceptible to external corrosion, which can result in leaks, endangering workers and the environment. Detecting and addressing corrosion promptly is crucial for preventing accidents and environmental harm. To address these challenges, a pipeline monitoring system has been developed using a Raspberry Pi Model 3B+ and advanced sensors. This system continuously monitors temperature, pressure, and external corrosion along pipeline routes. It utilizes a K-type thermocouple and a 1.2MPa pressure transducer for real-time data collection. Additionally, a laptop camera integrated with YOLOv8 enables visual inspection for detecting corrosion. The Raspberry Pi processes sensor data and images, triggering alerts for anomalies like temperature or pressure drops indicating leaks, or corrosion spots identified by YOLOv8. The system interfaces with ThingSpeak for remote data visualization and analysis, empowering operators to make informed decisions and take prompt corrective actions.

Exploring morphometric transformations in temperature-sensitive NiTi instruments alongside real-time intracanal temperature dynamics.

This study was twofold: (i) it aimed to investigate the morphometric changes of three temperature-sensitive nickel-titanium (NiTi) instruments at different temperatures, and (ii) to conduct an invivo real-time analysis of intracanal temperature changes. Changes in the shape and length of XP-Endo Shaper, XP-Endo Finisher, and XP-Endo Finisher-R were evaluated in real time whilst heated in a temperature-controlled water bath from 22 to 45°C. Instruments were fixed to a laminated water-resistant 1 mm graph paper attached to a stone block. Instruments were imaged whilst subjected to increasing temperature using a digital camera attached to an operating microscope. From recorded videos, still frames were extracted at 10-s intervals and changes in the length and shape of each instrument were measured and changes were plotted against time. Moreover, the intracanal temperature of distal roots of lower molars was measured invivo for patients attending the clinic for non-surgical root canal treatments. The temperature was measured using a K-type thermocouple probe inserted into the mid-root level after irrigating the canal with a solution set at room temperature (22°C) or heated to 45°C. The intraoral and intracanal temperatures were recorded using a video camera for 180 s at 5-s intervals to plot the change in the intraoral and intracanal temperature, after both irrigation solution temperatures, with time. The shape transformation of XP-Endo Shaper began at 31.5 ± 2.0°C and reached its optimal transformation at 35.1 ± 1.0°C. For the Finisher and Finisher-R, shape transformations began at 29.2 ± 1.9 and 26.9 ± 2.2°C reaching the optimal transformation at 33.9 ± 1.4 and 32.7 ± 1.7°C, respectively. The average decreases in lengths of XP-Endo Shaper, Finisher, and Finisher-R after full transformation were 0.43 ± 0.23, 1.07 ± 0.22, and 1.15 ± 0.22 mm, respectively. The intracanal temperature reached 32.9 ± 0.8 and 33.2 ± 1.0°C after 3 min of application of irrigation solutions set at 22 or 45°C, respectively. The tested instruments exhibited diverse changes in their shapes and lengths at varying temperatures. Despite the temperature of the irrigation solution, the intracanal temperature consistently remained lower than the intracanal temperature once equilibrium was reached. This highlights the importance of considering the temperature of irrigation solution during invitro testing of endodontic instruments.