Smoke Removal Research Articles

Smoke and Hot Gas Removal in Underground Parking Through Computational Fluid Dynamics: A State of the Art and Future Challenges

Smoke and Hot Gas Removal in Underground Parking Through Computational Fluid Dynamics: A State of the Art and Future Challenges

მიწისქვეშა ავტოსადგომების კვამლისაგან დაცვა ხანძრის დროს

The work examines current issues of fire, sanitary, hygienic and environmental safety of ventilation of underground parking lots. It has been established that, according to European standards, smoke removal systems with jet fans act much more efficiently than air ducts, quickly displacing smoke and exhaust gases towards the air intake grilles, from where and they come out. The design and parameters of the ventilation system are selected based on its ability to quickly and safely ensure the evacuation of people through smoke-free exits, as well as provide air parameters in the parking lot that meet the requirements of the design and installation of a ventilation unit in accordance with industry regulations of Georgia.

A Self-Supervised Network-Based Smoke Removal and Depth Estimation for Monocular Endoscopic Videos.

In minimally invasive surgery videos, label-free monocular laparoscopic depth estimation is challenging due to smoke. For this reason, we propose a self-supervised collaborative network-based depth estimation method with smoke-removal for monocular endoscopic video, which is decomposed into two steps of smoke-removal and depth estimation. In the first step, we develop a de-endoscopic smoke for cyclic GAN (DS-cGAN) to mitigate the smoke components at different concentrations. The designed generator network comprises sharpened guide encoding module (SGEM), residual dense bottleneck module (RDBM) and refined upsampling convolution module (RUCM), which restores more detailed organ edges and tissue structures. In the second step, high resolution residual U-Net (HRR-UNet) consisting of a DepthNet and two PoseNets is designed to improve the depth estimation accuracy, and adjacent frames are used for camera self-motion estimation. In particular, the proposed method requires neither manual labeling nor patient computed tomography scans during the training and inference phases. Experimental studies on the laparoscopic data set of the Hamlyn Centre show that our method can effectively achieve accurate depth information after net smoking in real surgical scenes while preserving the blood vessels, contours and textures of the surgical site. The experimental results demonstrate that the proposed method outperforms existing state-of-the-art methods in effectiveness and achieves a frame rate of 94.45fps in real time, making it a promising clinical application.

Smoke Removal Method of Industrial Images Based on Dark Channel Prior Approach and Second-Generation Wavelets

Smoke Removal Method of Industrial Images Based on Dark Channel Prior Approach and Second-Generation Wavelets

Synchronizing Detection and Removal of Smoke in Endoscopic Images With Cyclic Consistency Adversarial Nets.

Smoke removal is an important and meaningful issue for endoscopic surgery, which can enhance the visual quality of endoscopic images. Because it is practically impossible to construct a large training dataset of pair-matched endoscopic images with/without smoke, the Generative Adversarial Nets (GANs) based models are usually used for endoscopic image desmoke. But they have difficulties in either locating the accurate smoke area, or recovering realistic internal organ or tissue details. In this paper, we propose a new approach, called Desmoke-CycleGAN, which combined detection, estimation, and removal of smoke together, to improve the CycleGAN model for endoscopic image smoke removal. In addition, both pixel-level and perceptual-level consistency loss have been incorporated in the proposed model, which helps the model to be more stable and efficient for recovering realistic details in endoscopic images. The experimental results have demonstrated that this method outperforms other state-of-the-art smoke removal approaches with unpaired real endoscopic images.

Association Between Osteoporosis Self-Assessment Tool for Asians and Airflow Limitation in Japanese Post-Menopausal Women.

This study aimed to reveal the association between the osteoporosis self-assessment tool for Asians (OSTA) and airflow limitation (AL) in post-menopausal Japanese women. This cross-sectional study included 1580 participants undergoing a comprehensive health examination using spirometry and dual-energy X-ray absorptiometry. The OSTA was calculated by subtracting the age in years from the body weight (BW) in kilograms, and the result was multiplied by 0.2. The OSTA risk level was defined as low (>-1), moderate (-4 to -1), or high (<-4). AL was defined as forced expiratory volume in 1 s/forced vital capacity (FEV1/FVC) <0.7. The association between the OSTA and AL was assessed using logistic regression analysis. The prevalence of AL was significantly higher in the high OSTA group (15.3%) than in the low OSTA group (3.1%) (p<0.001). In multiple linear regression analysis, the OSTA was independently associated with FEV1/FVC. In logistic regression models adjusted for smoking status, alcohol consumption, current use of medication for diabetes, hyperglycemia, rheumatoid arthritis, second-hand smoke, and ovary removal showed a significantly higher risk of AL (odds ratio: 5.48; 95% confidence interval: 2.90-10.37; p<0.001) in participants with OSTA high risk than in those with OSTA low risk. These results suggest that the OSTA high risk indicates reduced BMD at the femoral neck and presence of AL in Japanese post-menopausal women aged ≥45 years.

Revealing patterns in improving the performance of portable smoke and heat removal devices when using fine sprayed water

An issue related to the application of portable smoke and heat removal devices for buildings and structures is to provide for their effectiveness when removing smoke and reducing temperature. That us why the object of this study was a change in the performance of a portable smoke and heat removal device when using finely sprayed water. Improved efficiency of the use of portable smoke and heat removal devices was based on experimental studies. It was proved that the reduction of smoke concentration and temperature in the room to the initial conditions was achieved for independent smoke dispersion in 5340 s, and cooling occurred in 3120 s. With the use of a smoke and heat removal agent during air supply, the smoke dissipated in 720 s, and cooling took 1560 s. And with the simultaneous supply of air and a sprayed jet of water, smoke dispersal occurred in 360 s, and cooling in 1020 s, respectively. To determine the efficiency of the smoke and heat release device, a calculation-experimental method has been devised that makes it possible to estimate the coefficient of the smoke and heat release agent when supplying air and water. According to experimental data, it was calculated that the coefficient of effectiveness of the smoke and heat removal devices when supplying air and water compared to the means when supplying only air increases by 2.1 times. The practical significance is that the results were taken into account when devising methodical recommendations for extinguishing fires. Thus, there are reasons to assert the possibility of targeted regulation of the processes of smoke reduction and temperature reduction through the use of a smoke and heat release device that simultaneously supplies air and finely sprayed water

Operational uptime and other measures of performance of an open car park in fire

192 coupled wind and fire CFD simulations were performed using ANSYS Fluent to study the wind and fire interaction in an open car park. The natural ventilation was insufficient for removal of smoke and heat for the majority of investigated fires. Blockage effect was observed for wind directions parallel to the open walls, which resulted in reduced smoke removal and higher smoke temperatures. With known probabilities of all the investigated wind speed and directions, we have estimated the percentage of time in which fire outcomes are acceptable. This value was coined as the car park operational uptime, and was 84.9 %–92.8 % in relation to the fire with HRR = 1.4 MW; 36.5 %–56.1 % at 4.0 MW; 34.1 %–54.4 % at 6.0 MW and 12.13–25.5 % at 8.8 MW. In 6.22 % of wind cases, the velocity inside the car park exceeded 3.0 m/s, which could potentially contribute to the growth of the fire. Limitations of the study include the assumed wind probability distribution relevant to the Warsaw region, the single location of the fire used in the assessment and the implicit modelling of topography and architecture through an introduced wind profile and terrain roughness model.

Problems of operation of positive pressure ventilators on the basis of surveys of Polish officers of the State Fire Service

Positive pressure ventilators (PPV) used by 97.7% of officers of the National Fire Service in Poland, are characterized by work that is not in line with the expectations of the firefighters. In order to improve the technical and operational features of these devices, a survey was conducted among 25,000 eligible firefighters, identifying the application of these devices, problems in use and expected development directions. A total of 682 officers voluntarily completed the survey. Based on their findings, it was determined that ventilators are most often used to smoke out buildings after or during a fire. Mentioned problems when using these devices were mainly noise (78.2%), exhaust emissions (68.5%), and impediments to mobility through the device’s relatively heavy weight (40.2%). Other inconveniences were mentioned by less than 20% of firefighters. Polish firefighters expect the development of these devices mainly in terms of the above-mentioned features (noise reduction (81.7%) and reduction of the weight and size of the ventilators (about 50%)). Other expectations relate to the improvement of smoke removal in buildings: increasing the efficiency of smoke removal (46.4%) and efficiency regarding the rate of smoke removal in a building by increasing the size of the incoming airflow from the building’s surroundings (33.2%). About 15% of firefighters expect changes in the operation of the ventilator itself, that is, an increase in the effective operating time (electric ventilators) and an increase in the device’s uptime. The aim of the article is to identify the issues encountered during the operation and to indicate the expected direction of development for PPV by users. This information can be used by engineers to initiate new development work on these devices.

Smoke deposition and extraction in compartment fires with different ignition sources

The paper presents the experimental research findings on the characteristics of smoke emission and deposition during compartment fires with different ignition sources: an open flame, a heated surface, local heating sources and exposed electrical conductors. The research involved the interior design and construction materials typical of residential and industrial premises: wood, linoleum and cardboard. Adaptive approaches were proposed to the creation of smoke deposition conditions at incipient fire stages using limited volumes of liquid. The foaming agent emulsion was found to be very effective for smoke suppression. The efficiency of several methods of smoke extraction using supply and exhaust ventilation was investigated. Efficient combined techniques of smoke extraction and deposition were identified. Smoke extraction was found to be most efficient at an air velocity of less than 3 m/s. The alternation of intermittent activation of the spraying system and supply and exhaust ventilation system is the most efficient method of smoke removal. Mathematical equations were derived to predict the characteristics of sprinkler and ventilation systems, providing effective smoke deposition and extraction.

Complex smoke removal in image: Integrating frequency learning network with data synthesis method

This paper introduces a novel neural network architecture and an enhanced data synthesis method that significantly boost the performance in removing complex smoke from images. The architecture features a multi-branch and multi-scale feature fusion design, which effectively integrates multiple feature streams and adaptively restores the background by identifying specific smoke characteristics within the image. A newly designed Fourier residual block is incorporated to capture frequency domain information, enabling the network to process and transform information across both spatial and frequency domains. To improve the network’s generalization ability and robustness, an in-depth analysis of the imaging process in smoky environments was conducted, leading to an improved method for synthesizing smoke images. This methodology facilitates the creation of a more varied and realistic training dataset, substantially enhancing the neural network’s capabilities in image restoration. Experimental results show that this approach is highly effective on both synthetic and real-world smoke datasets, outperforming existing image de-smoking methods in terms of quantitative metrics and visual perception. The code for this method is available at https://github.com/Exiagit/MFSR.

Industrial chimneys – as a potential art object

Industrial chimneys – as a potential art object

Controllable baffle-type exhaust-hood in home kitchen

In order to reduce the pressure of the central smoke shaft in high-rise apartments, a controllable baffle-hood was proposed to improve the smoke removal efficiency without increase the exhaust airflow rate in the kitchen. A series of baffle-type hoods with various locations and shape of panel were explored to evaluate the pollutant removal efficiency. The results showed that the baffle design reduces pollutant concentration by 8%–71% and lowers temperature by 0.8 °C–2.0 °C compared to conventional range hoods. A power function relationship was found between pollutant concentration and air velocity at cross-sectional of inlet. The panel is still a simple and useful technology in the home kitchen, if it can solve the convenience of cooking operations.

Research on New Whitening and Water-Saving Technology Based on Industrial Equipment

Energy conservation and consumption reduction have always been the goals pursued by the power industry. Based on these goals, this study explored a new type of whitening and water-saving technology for industrial equipment. Unlike existing direct heating and condensation heating technologies, the main innovation of this work lies in not changing the saturated wet flue gas before it is discharged into the atmospheric environment. A series of experiments were conducted on electrode plates with different wind speeds, supersaturation levels, and porosities using three principles, namely droplet electrostatic adsorption, ionic-wind-enhanced condensation, and droplet dipole deflection, through the construction of a parameter-adjustable and -controllable enthalpy and humidity chamber and a pilot development platform with a wind volume of 10,000 m3/h. In addition, the collection efficiency was calculated using thermodynamic laws. The results showed that, under the working conditions of white mist supersaturation of 5.77 g/kg, a hole opening rate of 70%, and a wind speed of 3 m/s, the water collection efficiency was the highest—close to 60%—verifying the feasibility of this technology. This technology not only eliminates white smoke but also saves water resources and has certain economic benefits, providing support for the development of industrial equipment for smoke removal in the future.

Modernization of an automated smoke removal control system in the silicate plant office building

The modernization of the smoke removal system in the security room of the silicate plant office building is considered. To maintain the specified excess pressure and temperature of the supply air in the security room, an air pressurization system is designed, consisting of two subsystems, one of which maintains excess pressure when the door to the security room is open, and the other when the door is closed. To select fans for the air pressurization system, the required air to ensure the maintenance of the specified excess pressure in the room is calculated. In accordance with fire safety rules, appropriate equipment for the air pressurization system is selected. Keywords safety, smoke removal, safety room, automation, automated control system, fan, fan performance, pressure, temperature

The Impact of Design Solutions for Smoke Ventilation during Commissioning: Organizing A Smoke Removal System in an InterApartment Corridor

The Impact of Design Solutions for Smoke Ventilation during Commissioning: Organizing A Smoke Removal System in an InterApartment Corridor

Smoke veil prior regularized surgical field desmoking without paired in-vivo data

Though deep learning-based surgical smoke removal methods have shown significant improvements in effectiveness and efficiency, the lack of paired smoke and smoke-free images in real surgical scenarios limits the performance of these methods. Therefore, methods that can achieve good generalization performance without paired in-vivo data are in high demand. In this work, we propose a smoke veil prior regularized two-stage smoke removal framework based on the physical model of smoke image formation. More precisely, in the first stage, we leverage a reconstruction loss, a consistency loss and a smoke veil prior-based regularization term to perform fully supervised training on a synthetic paired image dataset. Then a self-supervised training stage is deployed on the real smoke images, where only the consistency loss and the smoke veil prior-based loss are minimized. Experiments show that the proposed method outperforms the state-of-the-art ones on synthetic dataset. The average PSNR, SSIM and RMSE values are 21.99±2.34, 0.9001±0.0252 and 0.2151±0.0643, respectively. The qualitative visual inspection on real dataset further demonstrates the effectiveness of the proposed method.

Understanding surgical smoke in laparoscopy through Lagrangian Coherent Structures.

In laparoscopic surgery, one of the main byproducts is the gaseous particles, called surgical smoke, which is found hazardous for both the patient and the operating room staff due to their chemical composition, and this implies a need for its effective elimination. The dynamics of surgical smoke are monitored by the underlying flow inside the abdomen and the hidden Lagrangian Coherent Structures (LCSs) present therein. In this article, for an insufflated abdomen domain, we analyse the velocity field, obtained from a computational fluid dynamics model, first, by calculating the flow rates for the outlets and then by identifying the patterns which are responsible for the transportation, mixing and accumulation of the material particles in the flow. From the finite time Lyapunov exponent (FTLE) field calculated for different cross-sections of the domain, we show that these material curves are dependent on the angle, positions and number of the outlets, and the inlet. The ridges of the backward FTLE field reveal the regions of vortex formation, and the maximum accumulation, details which can inform the effective placement of the instruments for efficient removal of the surgical smoke.

HEATING SYSTEM OF PUBLIC DWELLING IN THE CENTRAL TRANSDNIPRIAN REGION (Part 2. Smoke removal devices and functional segmentation of the furnace)

HEATING SYSTEM OF PUBLIC DWELLING IN THE CENTRAL TRANSDNIPRIAN REGION (Part 2. Smoke removal devices and functional segmentation of the furnace)

Smoke removal technique of industrial scene images based on second-generation wavelets and dark channel prior model

Smoke removal technique of industrial scene images based on second-generation wavelets and dark channel prior model