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The purpose of this paper is to study the heat transfer effect of copper sensor and skin simulant on skin.

For the sensor, the physical and mathematical models of the thermal sensors were used to obtain the definite conditions in the heat transfer process of the sensor, and the heat transfer models of the two sensors were developed and solved respectively by using ANSYS WORKBENCH 19.0 software. The simulation results were compared with the experimental test results. For the skin, the numerical model of the skin model was developed and calculated. Finally, the heat transfer simulation performance of the two sensors was analyzed.

It is concluded that the copper sensor is more stable than the skin simulant, but the material and structure of the skin simulant is more suitable for skin simulation. The skin simulant better simulates the skin heat transfer. For all the factors in the model, the thermal properties of the material and the heat flux level are the key factors. The convective heat transfer coefficient, radiation heat transfer rate and the initial temperature have little influence on the results, which can be ignored.

The results show that there are still some differences between the experimental and numerical simulation values of the skin simulant. In the future, the thermal parameters of skin simulant and the influence of the thermocouple adhesion should be further examined during the calibration process.

The results suggest that the skin simulant needs to be further calibrated, especially for the thermal properties. The copper sensor on the flame manikin can be replaced by the skin simulant with higher accuracy, which will be helpful to improve the accuracy of performance evaluation of thermal protective clothing.

The application of computational fluid dynamics (CFD) technology can help to analyze the heat transfer simulation mechanism of thermal sensor, explore the influence of thermal performance of thermal sensor on skin simulation, provide basis for the development of thermal sensor and improve the application system of thermal sensor. Based on the current research status, this paper studies the internal heat transfer of the sensor through the numerical modeling of the copper sensor and skin simulant, so as to analyze the effect of the sensor simulating skin and the reasons for the difference.

In this paper, the sensor itself is numerically modeled and the heat transfer inside the sensor is studied.

The measurement of heat flux is of importance to the development of aerospace engine as basic physical quantities in extreme environment. Heat radiation is one of the basic forms of heat transfer phenomenon. The structure optimizing can improve the performance and infrared absorptivity of the thin film sensor.

This paper designed one kind of thin film heat flux sensor (HFS) with antireflective coating based on transparent conductive oxide thermopile. The introduced membrane structure is so thin that it has little impact on sensor performance. Fabrication of thin film sensors were fabricated by physical vapor deposition (PVD) process.

The steady-state and dynamic response characteristics of the HFS were investigated by calibration platform. The experimental results shown that the absorptivity of the membrane structure (for1070nm) improved compared with that before optimization. The sensitivity of heat flux gauge was 48.56 µV/ (kW/m2) and its frequency response was determined to be about 1980 Hz.

The thin film HFS uses thermopile based on Indium Tin Oxid and In2O3. The antireflective coating is introduced to hot endpoint of HFS to improve sensitivity on laser thermal source. The infrared optical properties of membrane layer structure were investigated. The steady-state and the transient response characteristics of the heat flux sensor were also investigated.

The aim of this paper is to investigate the behavior of a new nanometric particle NTC thermistor paste and thick films obtained by screen printing.

Nanometric powder of NTC thermistors based on complex spinel was made by calcination of an oxide mixture and ultra fast ball milling. Characterization of the new powder was done on compacts sintered in different conditions. Segmented thermistors were screen printed on alumina substrata, dried and fired in a conveyor furnace at 850°C/10 min. Segmented thermistors were indirectly heated by a glass sealed heater placed between them in the middle. The system was put in a tube with a regulated air flow to serve as a volume thermistor sensor based on heat loss.

The sintered thick film samples and NTC powder compacts measurements could help in choosing the optimal technology conditions during the production of NTC devices. The NTC segmented thermistors were suitable both for heated sensors and self heated sensors.

Low temperature thick film thermistor pastes based on nanometer powder of complex spinel are of interest due to their importance in sensor applications.

This work predicts that high temperature pastes of the same material can be realized with characteristics superior to those of low temperature paste such as NTC 3K3 or similar.

The need for sensors and actuators is an important issue in the field of smart textiles and garments. Important developments in sensing and heating textile elements consist in using non‐metallic yarns, for instance carbon containing fibres, directly in the textile fabric. Another solution is to use electro‐conductive materials based on conductive polymer composites (CPCs) containing carbon or metallic particles. The purpose of this paper is to describe research based on the use of a carbon black polymer composite to design two electro‐conductive elements: a strain sensor and a textile heating element.

The composite is applied as a coating consisting of a solvent, a thermoplastic elastomer, and conductive carbon black nanoparticles. In both applications, the integration of the electrical wires for the voltage supply or signal recording is as discreet as possible.

The CPC materials constitute a well‐adapted solution for textile structures: they are very flexible, and thus do not modify the mechanical characteristics and general properties of the textile structure.

In the case of the heating element, the use of metallic yarns as electrodes makes the final structure a more rigid. This can be improved by choosing other conducting yarns that are more flexible, or by developing knitted structures instead of woven fabrics.

The CPC provide a low cost solution, and the elements are usually designed so as to work with a low voltage supply.

The CPC has been prepared with a solvent process which is especially adapted to flexible materials like textiles. This is original in comparison to the conventional melt‐mixing process usually found in literature.

For the production of sensor elements, thick film technology can be used. Advantages of this technology such as ease of production, low cost, high reliability and the possibility of integration with front‐end electronic circuits, make the thick film sensor an interesting alternative to existing sensor elements. In this paper two examples of thick film thermal sensors are presented.

Pyrolysis means to heat a material up to high temperatures at which its molecular structure is thermally cracked. The residues of the heated material are gases and ashes. In modern consumer ovens this method is used to clean the walls of the oven cavity. The cavity is heated up to about 480°C. At this temperature the dirt sticking on the walls is thermally cracked into gases and ashes. The approach of the system described in this paper is to estimate the quantity of dirt to be pyrolysed in the cavity. This is done by using a gas sensor. The sensor measures the concentration of the gaseous residues in the exhaust air of the oven. Evaluation of the sensor signal makes it possible to minimise the energy consumption during the process. Furthermore, the sensor can be used as a safety device.

The purpose of this paper is to provide the details of developments to researchers in test apparatus and evaluation methods to rate the thermal protective performance (TPP) of firefighters’ clothing under high-temperature and high-humidity condition.

This review paper describes the influence laws of moisture on thermal protection and the moisture distribution in actual fire environment. Different evaluation methods used for assessing the effect of moisture on the TPP were investigated, with an emphasis on test devices, evaluation indexes as well as their relationship and limitations.

The moisture from the ambient, clothing and human perspiration plays an important role in determining the TPP of firefighter protective clothing. It is obvious that research on moisture-driven heat transfer in firefighter’s clothing system are comparatively little, primarily focussing on pre-wetted methods of multi-layer fabric. Further studies should be conducted to develop more standardized moistening systems and improve the current calculation methods for evaluating the performance of protective clothing. New explorations for heat and moisture transfer mechanism in protective clothing should be investigated.

Protective clothing is the efficient way to provide fire-fighting occupational safety. To accurately evaluate the TPP of protective clothing under high-temperature and high-humidity condition will help to optimize the clothing performance and choose the proper clothing for providing firefighters with the best protection under multiple thermal hazards.

This paper is offered as a concise reference for scientific community further research in the area of the TPP evaluation methods under high-temperature and high-humidity condition.

The purpose of the paper is to improve the control of vapour phase soldering (VPS). To enable better productivity and assembling quality, the industry needs to provide precise control and measurements during assembling. In the paper, a special monitoring method is presented for VPS to enable improved process control and oven state identification.

The work presents the investigation of the workspace with dynamic and gage type pressure sensors in fusion with thermocouples. Different sensors were evaluated to find an appropriate type. The relation between the temperature and the pressure was investigated, according to the setup of the oven. The effect of inserting a printed circuit board (PCB) on the pressure of the vapour inside the oven was also investigated with the pressure/power functions.

It was found that the novel gage-type sensors enable better precision than solutions seen in previous literature. The sensors are able to monitor the decreasing vapour concentration when a PCB is inserted to the workspace. It was found that there is a suggested minimum power to sustain a well-developed vapour column for soldering in saturated vapour. An inflexion point highlights this in the pressure/power function, in accordance with the temperature/power curve.

The research presents original works with aspects of a novel sensor fusion concept and work space monitoring for better process control and improved soldering quality.

Atmospheric dependent, gas sensitive resistors seem to be good candidates for detecting critical air pollution levels. Recently, great progress has been made in the development of various sensor types, but less attention seems to be paid to the integration of sensor elements with different characteristics. The aim of this international project is to develop a smart hybrid gas multi‐sensor module for environmental applications, i.e. by combining classical thick‐ and thin‐film elements with polymer‐film based sensors and also a signal processing ASIC within a single package, which should be useful for all sensor types. The module should enable multi‐sensor operation as well, when connected to an intelligent signal‐processing unit.