Temperature Of Mixture Research Articles

Automated Control System for Drum-Type Biofermenter

Modern production increasingly relies on the implementation of automated control systems to improve the efficiency, precision, and safety of technological processes. In the agricultural sector, complex technologies involve the processing or disposal of organic waste through biotransformation or degradation. These processes occur in multiple phases, each requiring specific operating conditions. To enhance overall effectiveness, there is a need for an automated system capable of monitoring the biothermal reaction process and managing the operational modes of a biofermenter in accordance with the current phase of organic waste processing. (Research purpose) The aim of this research is to develop an automated control system for a drum-type biofermenter. (Materials and methods) The study was conducted using an experimental drum-type biofermenter operating under conditions of aeration of the processed organic matter. The automated control system is built on a three-level architecture: the upper level consists of a server and an operator’s automated workstation, the middle level includes a programmable logic controller, and the lower level comprises sensors and actuators. Temperature inside the bioreactor is measured using resistance temperature detectors housed in immersion sleeves. Airflow is calculated based on readings from a diff erential pressure sensor. The drum’s rotation speed is monitored using an optical non-contact sensor. (Results and discussion) The proposed control system enables automated monitoring of key processing parameters and supports effective management of the biofermenter’s operating modes. Testing demonstrated the system’s ability to accurately monitor and display the mixture temperature, aeration airfl ow, and drum rotation speed. The system also allows for rapid mode adjustments to operating modes and facilitates the identification of optimal parameters for efficient organic waste processing. (Conclusions) The automated control system for organic waste processing in a drum-type biofermenter ensures continuous monitoring of key parameter. This capability facilitates the identification of optimal operating modes and the development of adjustment algorithms tailored to different types of organic mixtures, ultimately contributing to the production of a high-quality end product.

Dehydration of lean gas from carbon black production technology: process design scheme and techno-economic assessment

Abstract In pyrolysis, liquid hydrocarbons are partially combusted with air, followed by water quenching, which produces carbon-black particle aggregation and lean gas. The lean gas consists of H2, CO, CO2, and C2H4 constituents, and dominant water vapor and nitrogen contents. The study synthesizes process design schemes based on dew point techniques to dehydrate lean gas economically and calculates the process’s payback period. A chart was prepared to determine the dew point temperature of gas mixtures at different operating pressures and water vapor compositions. Two process design schemes were proposed to achieve up to 98 % dehydration of lean gas. The Techno-Economic Analysis (TEA) was employed to assess the economic viability of various process schemes by estimating capital expenditures (CAPEX), operational expenditures (OPEX), and the payback period. The process is capable of producing dry gas (fuel gas) at a cost as low as $0.20 per kilogram. Overall, the process design scheme offers an environmentally friendly, sustainable, and cost-effective solution for dehydrating wet lean gas, making it suitable for long-distance pipeline transportation.

Feasibility Study of Waste Rock Wool Fiber as Asphalt Mixture Additive: Performance Test and Environmental Effect Analysis

To investigate the feasibility of utilizing waste rock wool fiber as an additive in asphalt mixtures for resource recycling, this study evaluates and analyzes the performance of asphalt and asphalt mixtures, as well as their environmental benefits. Initially, the properties and mechanisms of modified asphalt mortar are examined under different shapes (powdery rock wool fiber (RWP) and fibrous rock wool fiber (RWF)) and varying rock wool fiber contents (0%, 1%, 2%, 3%, and 4% of matrix asphalt mass). Subsequently, the pavement performances of asphalt mixtures with different RWF contents (0%, 0.1%, 0.2%, 0.3%, and 0.4% of asphalt mixture mass) are compared. The environmental and economic impacts of RWF-modified asphalt mixtures are assessed using the life cycle assessment (LCA) method and the benefit cost analysis (BCA) method. Finally, the carbon property ratio (CPR), an innovative index, is proposed. It comprehensively evaluates the pavement performances and economic benefits of RWF modified asphalt mixtures in relation to carbon emissions (CEs). The results indicate that compared to RWP, RWF primarily functions as an inert fiber stabilizer. It provides a physical reinforcing effect through its three-dimensional network skeleton structure. Both RWP and RWF-modified asphalts exhibit improved performance compared to matrix asphalt. RWF demonstrates superior temperature susceptibility and high temperature performance. The optimal contents for achieving the best high temperature, water stability, and low-temperature crack resistance performances of RWF-modified asphalt mixtures are 0.3%, 0.2%, and 0.2%, respectively. As the RWF content increases, the energy consumption (EC) and CEs during the pavement construction stage slightly rise within an acceptable range, while positive economic benefits also increase. Additionally, the CPR index can comprehensively assess the favorable effects of pavement performances or economic benefits against the adverse effects of CEs. It offers theoretical guidance for the design of optimal rock wool fiber content.

Correlation Studies on Sensorial and Textural Characteristics of Mohanthal During Optimization of Sugar Syrup Concentration

ABSTRACT Traditionally, Halwais used their experience to determine the concentration of sugar syrup, which plays a critical role in the body and texture of Indian sweets such as Mohanthal. However, variations in sugar syrup concentration can significantly alter the final product’s quality. This study aimed to optimize the sugar syrup concentration and ghee-besan mixture temperature and to establish correlations between the sensory, textural, and color attributes of Mohanthal. Preliminary trials determined the optimal roasting temperature and the use of freshly milled besan. Three sugar syrup concentrations (70, 75, and 80°Brix) and three mixture temperatures (75, 100, and 125°C) were evaluated. Significant effects (p < 0.05) of syrup strength, mixing temperature, and their interaction were observed on hardness, cohesiveness, springiness, gumminess, chewiness, color indices (browning and whiteness), and moisture content. The highest sensory acceptance was achieved using 75°Brix sugar syrup added at 100°C. Using powdered sugar instead of syrup resulted in a less desirable product with poor texture and sensory quality. The findings provide a scientific basis for standardizing Mohanthal production, enabling industrial-scale manufacturing with consistent quality. Future research is recommended to focus on shelf-life extension, packaging technologies, and adaptation of optimized processes for large-scale production.

Dynamic modulus and viscoelastic properties of rock compound asphalt modified asphalt mixtures

Abstract The rock-compound asphalt-modified additive (RCA), synthesized from natural rock asphalt, nano-high fractions, and other components, is a novel high-modulus asphalt mixture additive. When applied to pavement surface layers, it enhances fatigue and rutting resistance. This study investigates the influence of RCA dosage on the high-temperature stability, fatigue resistance, and water stability of asphalt mixtures and identifies the optimal binder/aggregate ratio and RCA content. Results demonstrate that RCA incorporation significantly improves rutting resistance, fatigue resistance, and water stability of asphalt mixtures. The optimal mix road performance is achieved at a binder/aggregate ratio of 4.0% and an RCA dosage of 1.0%. Under high-temperature and low-frequency loading conditions, the dynamic modulus of RCA-modified high-modulus asphalt mixtures substantially exceeds that of conventional mixtures. Viscoelastic behavior depends on mix gradation and temperature: increasing coarse aggregate proportion or decreasing temperature reduces creep deformation in the asphalt mixture.

Identifying key parameters for reliable assessment of entomopathogenic nematodes viability as affected by spray application stress-related factors.

Conventional pesticide application equipment (PAE) is used to apply entomopathogenic nematode (EPN)-based bioinsecticides, but their closed hydraulic systems could raise the temperature of the spray mixture up to 40 °C, potentially harming EPN, since temperatures above 30 °C can immobilize nematodes, reducing their infective capacity. This study aimed to identify the most suitable method to evaluate EPN viability under the effects of PAE technology. Three EPN species-Heterorhabditis bacteriophora, Steinernema feltiae, and Steinernema carpocapsae-were exposed to thermal stress (10, 20, 30, and 40 °C for 270 min) to simulate spray application conditions. Three viability evaluation methods were compared: prodding stimulation, NaCl chemical stimulation, and no stimulation. Viability was measured by two parameters depending on the assessment method: % actively EPN moving (activity), or % total live EPN, both actively moving and immobile (survival). Additionally, a novel parameter estimating non-lethal stress (Δnl s) was defined by measuring the live but inactive EPNs. NaCl stimulation was optimized comparing different concentrations and durations and then set at 0.1 g mL-1 for 1 min. Temperature significantly affected EPN viability over time. Temperatures around 20 °C preserved optimal conditions, and above 30 °C negatively affected EPN viability, with mortality close to 80% within 90 min at 40 °C. Prodding (measuring survival) yielded higher viability compared to NaCl and no stimulation, which measured activity. Non-lethal stress parameter increased accordingly to stress increment showing potential as EPN stress-marker. The study concluded that combined measurement of survival, activity and non-lethal stress should be considered in EPN viability assessments when designing PAE to ensure high efficacy of biocontrol agents. © 2025 The Author(s). Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Prediction for Critical Temperature and Critical Pressure of Mixtures by Improved Empirical Correlations

Prediction for Critical Temperature and Critical Pressure of Mixtures by Improved Empirical Correlations

Physics-Informed Multifidelity Gaussian Process: Modeling the Effect of Water and Temperature on the Viscosity of a Deep Eutectic Solvent.

Knowledge of shear viscosity as function of temperature and composition of an aqueous deep eutectic solvent mixture is essential for process design but can be highly challenging and costly to measure. The present work proposes to combine a small set of experimentally determined viscosities with a small set of simulated values within a linear multifidelity approach to predict the dependency of shear viscosity on temperature and composition. This method provides a simple approach that requires a physics-based transformation of viscosity data prior to training, without the need for additional data such as densities. This allows reduction in cost with experiments and reduces the number of experiments and simulations required to characterize a specific system. The data-driven component of the model does not concern the viscosity itself but rather the excess free energy term within the framework of a mixture viscosity model according to Eyring's absolute rate theory. Moreover, we illustrate the application of kernel-based machine learning approaches to daily research questions where data availability is limited compared to the data set size typically required for neural networks.

The Solubility of Four DNA and RNA Bases at Five Different Temperatures in Aqueous Mixtures of Dipolar Aprotic Acetonitrile and the Insights into the Solvation Phenomena

The Solubility of Four DNA and RNA Bases at Five Different Temperatures in Aqueous Mixtures of Dipolar Aprotic Acetonitrile and the Insights into the Solvation Phenomena

Dynamics of unsteady premixed flames in meso-scale channels and the effects of varying the wall heating conditions

Understanding the dynamics of flames at small scales opens up opportunities to enhance the performance of small-scale power generation devices, micro-reactors, fire safety devices and numerous other systems that confine combustion to micro/meso scales. The current study investigates the dynamics of laminar premixed methane–air flames in meso-scale channels. A cylindrical quartz tube, functioning as an optically accessible meso-scale combustor, is externally heated by a primary heater to facilitate the auto-ignition of the reactant mixture flowing through the tube. Experiments were conducted over a wide range of Reynolds numbers ( $Re$ ) and equivalence ratios ( $\Phi$ ). Apart from the previously documented observations of unsteady flames with repetitive extinction and ignition (FREI) characteristics, this study identifies an additional unsteady propagating flame (PF) regime. While FREI appeared at stoichiometric and fuel-rich conditions, PFs were observed at the equivalence ratio of $0.8$ . Unlike the FREI regime, where the flame extinguishes after a characteristic travel distance, PFs continue to travel till they reach the upstream end of the combustor tube, where they extinguish upon encountering a meshed constriction. These flames are associated with a characteristic heat release rate oscillation that couples with the pressure fluctuations at frequencies close to the natural harmonic of the combustor tube. The study further investigates how variations in the wall temperature profile affect the dynamics of FREI and PF regimes. To achieve this, a secondary heater is introduced at varying distances from the primary heater, effectively imposing distinct bimodal wall heating profiles over the combustor tube. The observations and trends from the study were justified using simplified theoretical arguments based on the estimate of the mean flow temperature of the reactant mixture and a flame propagation model that accounts for wall heat losses. The novel findings from this work provide valuable insights that can significantly impact the design and development of advanced micro/meso-scale combustion systems.

Synergistic improvement on temperature and moisture stability of asphalt mixture with steel slag aggregate coated by waterborne polyurethane

Synergistic improvement on temperature and moisture stability of asphalt mixture with steel slag aggregate coated by waterborne polyurethane

Numerical simulations of a turbulent lifted hydrogen flame in vitiated coflow with flamelet generated manifold approach

Abstract Numerical investigation of turbulent lifted H2/N2 jet flame in vitiated hot coflow is presented. Turbulent combustion modeling is performed by using flamelet generated manifold approach and presumed probability density function for turbulence-chemistry interaction. Sensitivity analysis of scalar dissipation modeling for mixture fraction and progress variable suggests that the combustion temperature is more sensitive to mixture fraction variance, whereas the flame lift-off height is more sensitive to progress variable variance. The present simulations provide overall good agreements with experimental measurements for mixture fraction, temperature, and chemical species, which gives further information regarding the global flame structure and reaction characteristics. Investigation on mixture fraction conditional scatter plot reveals that the evolution of lifted flame branch and flame dynamics are well captured. Two combustion modes are identified in flame zone. It indicates that non-premixed combustion dominates in core flame region, however low probability of premixed combustion is observed occurring in central fuel-rich zone.

Study on hangfire failure mechanism in firearm firing-ignition systems

To investigate the hangfire failure mechanism in firearm firing-ignition systems, gas pressure responses were experimentally analyzed using a firing-ignition simulation test device. Pressure characteristic parameters were statistically evaluated using the “3σ” criterion to establish the hangfire failure thresholds. A finite element model simulating the mechanical-thermal-chemical multi-mechanism coupling process during primer mixture ignition was developed and validated against experimental results. The effects of percussion energy, interlocking gap, charge surface height, and anvil height on primer mixture temperature and gas pressure dynamics were systematically studied. Single-factor and coupled two-factor analyses revealed critical failure boundaries and their influence on ignition performance. Results indicate that reduced percussion energy and charge surface height, combined with increased interlocking gap and anvil height, diminish energy conversion efficiency, delay hotspot formation, and prolong pressure initiation.

Low-cost ceramic membrane supports based on ukrainian kaolin and saponite

The synthesis of ceramic membranes using natural raw materials, especially kaolin and saponite clays, is a rational approach to reducing the cost of ceramic membranes for water purification. This study investigated the effect of sintering temperature and phase composition of the initial mixture on the physicochemical, mechanical, and transport properties of ceramic membranes based on kaolin and saponite. The initial clay components and ceramic membrane matrices obtained from them were characterised using diffraction methods, FTIR and thermal analysis. It was shown that the kaolin phase primarily determines the structural-adsorption characteristics of the ceramic membrane matrices. The determined mechanical properties indicate a significant influence of temperature and composition of the initial mixture on the flexural strength limit, with the selected ceramic matrices being in the range of 10–16 MPa. The electrical properties suggest potential resistance to contamination during operation. The revealed a macroporous structure of the obtained membranes provides their good permeability for pure water.

Modeling two-dimensional linear detonation engines with ANSYS Fluent package

In this paper methodology for simulation of the Rotating Detonation Engines in ANSYS Fluent is developed. The overall approach relies on a 2D geometry, global reaction models of the homogeneous kerosene-air mixture, and appropriate boundary and initial conditions. It leads to development and steady propagation of the detonation wave in a periodic channel. The wave structure and basic parameters are analyzed and compared to the data in the literature and an ideal Chapman-Jouguet detonation. The trends of the detonation speed are analyzed for range of equivalence ratios, mixture temperatures and pressures, mesh resolution and combustion models. The software is capable of simulation of complex phenomena occurring in the detonation wave. A cellular structure visible in real detonations can be predicted by CFD, although its scale differs due to simplifications employed. The study shows that this methodology can be used for analysis of propulsion systems operating on detonative combustion. It also indicates its limitations and areas for improvements. ANSYS Fluent flexibility and user-friendly interface combined with this methodology help the user concentrate on R&amp;D instead of coding.

Analytical Investigation of TAR for Enhancing Performance Using Varied Stack configuration and Varied Working Fluid

Thermoacoustic cooling, which uses sound waves to transfer heat, is an environmentally friendly and simple alternative to conventional refrigeration. Gas mixture adjustment to improve cooling performance is understudied compared to pure gas use. Previous studies focused on pure gas systems, but helium-argon combinations can boost thermoacoustic efficiency. Studying these gas mixtures' synergy could improve cooling efficiency. This study examined different working fluid i.e. pure gas and blend of helium-argon gas to a Thermoacoustic Refrigerator (TAR) to improve performance. A helium-argon gas mixture's thermoacoustic COP and temperature differential were measured experimentally. The resonator stacks were made of spiral, parallel, and honeycomb with polynamide nylon 6 material. The study focuses on cooling load, frequency, and operating pressure. Our findings suggest that adding helium-argon gas to TARs may improve their performance, broadening refrigeration and cooling applications. Energy was saved by lowering the thermoacoustic activity start temperature using this mixture. The right mix of these gases can outperform pure gas systems, enabling sustained cooling, according to experiments. Researchers employ Mylar, Photographic films, and other stack materials to cool TAR, but 3D printing can create intricate stack structures with polynamide nylon 6. This study highlighted the use of single gas and blend of helium-argon gas mixture to explore polynamide nylon 6 stack materials with varied geometries. The system can be tested with other stack material and different gases at an optimum frequency of 500Hz, the cooling performance was observed. The experimental data simulated with the DELTAEC software

A general viscosity model for high moisture extrudates of pea protein isolates/gluten blend

A capillary pre-shearing rheometer, Rheoplast®, allowing for simulation of an extrusion process, was used to determine the viscosity of 60/40 pea protein isolate/gluten blends previously extruded at different temperatures (130 °C, 140 °C, 150 °C) and moisture contents (50%, 55%, 60% w/w). Electronic microscopy and mechanical testing showed that the materials displayed distinct anisotropic and fibrous structures. Pressure profiles were determined over an apparent shear rate range of 10–104 s−1, using capillary dies with length/diameter (L/D) ratios 8, 16, and 32 (D = 1 mm). For all materials, the pressure profiles are regular, suggesting the absence of wall slip. All flow curves could be fitted with the Ostwald–de Waele model. The values of consistency index (K), ranging from 480 to 5000 Pa.sn, and those of the flow index (n), from 0.25 to 0.7, were inversely correlated, reflecting the effect of material structuring. Furthermore, the time-temperature superposition principle was extended to account for the influence of water content by introducing the glass transition temperature (Tg) of the protein mixture with curve shift factors depending linearly on Tg/T. All results can then be fitted using a Carreau model, describing the viscous behavior within the range [1, 105 s−1] with plateau viscosity (η0) values varying between 240 and 1050 Pa.s. Finally, by extrapolating Bagley plots to L/D = 0, entry pressure was derived, and, consequently, apparent elongational viscosity was determined, leading to Trouton number values around 100. Results are interpreted by structural differences and the viscosity model can be used for computer simulation of flow in the die.

Experimental and Chemical Kinetic Study on Laminar Burning Velocity of p-Xylene + Air Mixtures at Elevated Temperatures

ABSTRACT Xylene, a significant aromatic component in fuels like gasoline, diesel and aviation fuels, plays a crucial role in combustion dynamics. Analyzing their flame dynamics under engine-relevant conditions is essential for a comprehensive understanding of their combustion behavior and performance. To analyze the flame propagation behavior and combustion chemistry, the present study focuses on the experimental and chemical kinetic study on laminar burning velocity (LBV) of p-xylene + air mixture at elevated temperatures (361 - 638 K) for various mixture equivalence ratio (ϕ = 0.7 - 1.4) under atmospheric pressure conditions using externally heated diverging channel method. The present measurements were compared with the predictions from chemical kinetic models, namely, Narayanswamy, Kukkadapu, and Yuan. The Yuan model showed an overall good match with the present measurements at various mixture equivalence ratios and temperatures. The LBV follows a parabolic profile with an equivalence ratio and peaks at a slightly rich mixture equivalence ratio, ϕ = 1.1, whereas the profile of the temperature exponent shows a reverse parabolic profile with minima at ϕ = 1.0. The present experimental results show that LBV increases with mixture temperatures and the peak LBV is increased by 32.4 cm/s as the mixture temperature is increased from 500 to 600 K. The present study extends LBV measurements up to 638 K, compared to the existing reported LBV at 353 K. This higher temperature LBV data will help optimize chemical kinetic models for improved accuracy and enhanced understanding of combustion dynamics, which helps reduce emissions of nitrogen oxides, carbon monoxide, and particulate matter. By optimizing flame propagation and maximizing energy release, cleaner and more efficient combustion systems can achieve higher efficiency, resulting in lower fuel consumption and minimized environmental impact.

Phase Transformations in MOFs Induced by Adsorbate Exchange.

Deformation of nanoporous materials induced by gas adsorption is a ubiquitous phenomenon that plays an important role in adsorption separations, gas and energy storage, nanosensors, actuators, secondary gas recovery, and carbon dioxide sequestration in coal and shale reservoirs. One of the most prominent examples is the breathing phase transformation in metal-organic frameworks (MOF) associated with significant volume variations upon adsorption and desorption of guest molecules. Here, we present a theoretical framework for the quantitative description of the breathing transitions upon adsorption of binary mixtures, drawing on the practically important example of the displacement of methane by carbon dioxide in the MIL-53 MOF. The proposed approach, which is based on the concept of adsorption stress, reveals the mechanisms of framework deformation and breathing phase transformation between the large pore (LP) and narrow pore (NP) conformations. We show that when pure CH4 adsorption proceeds entirely in the LP phase, even a small addition of CO2 makes the LP phase unstable and triggers conversion to the NP phase, and the reverse NP-LP transformation occurs upon further displacement of CH4 by CO2. The theoretical predictions of adsorption and strain isotherms are confirmed by an agreement with the literature experimental studies performed on MIL-53(Al) at different CH4-CO2 mixture pressures and temperatures. The proposed general approach is applicable to other flexible nanoporous structures and gas mixtures.

One-Dimensional Simulation on the Propagation of Cool and Hot Flames for Methanol/n-Heptane Dual-Fuel Premixtures

ABSTRACT Numerical simulations of stratified methanol/n-heptane dual-fuel mixtures with various stratification configurations are conducted using a skeletal chemistry mechanism. The transient initiation and propagation of cool and hot flames are studied under various thermal and compositional stratifications under engine-like conditions. The ignition delay times (IDTs) for stratified dual-fuel premixtures are significantly reduced when the initial temperature is within the negative temperature coefficient (NTC) region. Different initiation regimes are identified under various initial conditions. When the initial temperature of the n-heptane mixture is below or within the NTC region, the propagation of a cool flame front dominates the early stage of ignition. When the initial temperature is within the NTC region, hot flames are formed behind the cool flame front where the reactivity is enhanced due to the thermal stratifications. The lower temperature at the mixing layer tends to shorten the IDT. A double-flame structure for the coexistence of cool and hot flames is observed. At higher temperatures, the high reaction rate for the n-heptane/air premixture plays the dominant role during the decomposition process. Thus, high-temperature kernels appear in the n-heptane/air mixture. By increasing the equivalence ratio of the n-heptane/air mixture, the double-flame structure transitions to a single-flame structure in which the hot flame propagation plays the dominant role.