Operating Conditions Research Articles

Evaluation of Damper Winding Application in a PMSM Under Different Operating Conditions

Evaluation of Damper Winding Application in a PMSM Under Different Operating Conditions

High-frequency Resonance Suppression of Railway Traction Power Supply System Based on the Combination of Single-tuned and C-type Filters

Background: Railroad transportation in the actual operation process, there are also many dangerous accidents caused by resonance, which greatly affect the safety of railroad transportation. A comprehensive examination of the operational dynamics within the power branch of a traction substation is imperative for sustaining system equilibrium. Discrepancies between these facets pose a potential threat to the safety of railway transport. Thus, a meticulous analysis of highfrequency resonance characteristics and the formulation of effective suppression techniques become paramount. Objective: Harmonics from grid-side locomotive traction braking are scrutinized under different operational scenarios and different train runs. The aim is to develop an effective harmonic management strategy to normalize the THD and thus maintain the traction power supply system to become more stable. Methods: This study investigates the high-frequency harmonic resonance characteristics using a control variable approach. Harmonics and negative sequences generated during locomotive traction braking under different operating conditions are investigated by means of extensive analysis. These challenges require the implementation of a harmonic management method. This method uses a combination of two monotonic filters and a C filter in parallel. This method applies to different operating conditions and can dynamically adapt harmonics to changes in the number of trains, which is related to the actual dynamics of the traction power system closely. Results: A comparative evaluation of seven operating conditions shows that the filter in this patent exceeds the efficiency of existing methods. The filter reduces the fluctuations during spectral changes, and the voltage distortion rate decreases from the previous 2.33% to 0.55%, making it more adaptable and promising effective harmonic management in high voltage and high current situations. Conclusion: Through multiple simulation tests, a synergistic configuration involving the C-type filter and two single-tuned parallel connections under regenerative braking conditions emerges. This refined, patented filter design not only mitigates the impact of negative sequence during the filtration process but also substantially diminishes high harmonics and THD.

Dynamic modeling and analysis of compressed air energy storage for multi-scenario regulation requirements

Compressed air energy storage (CAES) technology has received widespread attention due to its advantages of large scale, low cost and less pollution. However, only mechanical and thermal dynamics are considered in the current dynamic models of the CAES system. The modeling approaches are relatively homogeneous. CAES power stations have gradually increased the demand for auxiliary services such as frequency modulation mode and voltage regulation mode in addition to the peak regulation mode. Therefore, it is urgent to pay attention to the dynamic response characteristics at shorter time scales. Due to the lack of an accurate and complete dynamic model of the CAES system for multi-scenario adaptation requirements, the development of system optimization design and control technology has been severely limited. The paper establishes a dynamic model of advanced adiabatic compressed air energy storage (AA-CAES) considering multi-timescale dynamic characteristics, interaction of variable operating conditions and multivariate coordinated control. The simulation data is compared with the measured data of the peak regulation, frequency regulation and voltage regulation scenarios of the Jintan Salt Cave CAES (JTSC-CAES). The results show that the deviation of the dynamic model is <7 %, which verifies the validity and accuracy of the proposed AA-CAES dynamic model. The established model and research results provide the theoretical model foundation for dynamic characteristic research, system design and optimization control of the JTSC-CAES.

Optimization of Ecofriendly L-Fe/Ni Nanoparticles prepared using extract of black tea leaves for Removal of tetracycline antibiotics from Groundwater by Response Surface Methodology

This article focuses on employment of nanotechnologies in remediation of tetracycline antibiotics (TC) from groundwater by green synthesized bimetallic Fe/Ni supported by limestone particles. An in-situ green synthesis nanoparticles was prepared using black tea leaves extract to generate a L-Fe/Ni nanocomposite. The synthesized nanocomposite was characterized using several techniques, such as, X-Ray Diffraction (XRD), Scanning Electron microscopy (SEM), transmission electron microscope (TEM), Energy dispersive X-ray (EDX), FTIR (Fourier Transform-Infra Red) spectroscopy and surface area. We then use response surface methodology (RSM) to optimize the synthesis process and evaluate the effectiveness of the prepared nanocomposite for tetracycline remediation. We took different simulated concentrations of the TC contaminant without relying on actual TC concentrations in grounwater, the best removal of the TC contaminant in batch study was investigated with relying on the initial concentrations of TC and other experimental factors such as pH, adsorbent nanomaterial concentration and time. A pilot plant was then constructed to eliminate the TC contaminant from groundwater in different concentrations, where the removal efficiency was found decreased with increasing in the concentration of the TC Many parameters affecting the removal mechanisms in statistical and continuous systems were examined to select the best results that accomplish the maximum elimination rate. With the improved operating conditions, (L-Fe/Ni concentration: 1500 mg/L; concentration of TC: 20 mg/L; pH: 7.2; contact time: 128 min), removal percent of TC was found 87 % based on RSM system. The L-Fe/Ni reactive medium of continuous column has a main role in slowing down the movement of the TC plume. This study showed that the ecofriendly nanocomposite could be an appropriate and novel method for remediation of antibiotics and other contaminants in groundwater.

Enhancing prediction of elemental composition through machine learning decision tree models for biomass gasification optimization

Abstract The worldwide transition to cleaner, sustainable energy sources, prompted by population growth and industrialization, responds to uncertain fossil fuel prices and environmental concerns, highlighting the substantial benefits of renewable energy in reducing greenhouse gas emissions and addressing climate change. Derived from non-fossilized organic materials, biomass emerges as a significant and sustainable contributor to renewable energy. Its diverse nature is complemented by a range of conversion technologies, encompassing combustion, pyrolysis, gasification, and liquefaction, providing versatile avenues for biomass energy transformation. Gasification, the transformative process of converting organic matter into combustible gases under controlled oxygen levels, is accomplished through direct oxygen supply or pyrolysis. This method yields a dependable gaseous fuel versatile for heating, industrial processes, power generation, and liquid fuel production. Machine learning employs advanced statistical techniques for modeling across diverse industries, showcasing particular efficacy in optimizing thermochemical processes by precisely identifying the optimal operating conditions required for achieving desired product properties. These models utilize proximate biomass data to predict the elemental compositions of N2 and H2. Assessment of both single and two hybrid models indicated that the introduced optimizers significantly enhanced the estimation of N2 and H2 when combined with Decision Tree (DT), with Decision Tree Coupled with Artificial Hummingbird Algorithm (DTAH) proving particularly effective. Notably, DTAH demonstrated outstanding performance with remarkable R 2 values of 0.990 for N2 and 0.992 for H2. Additionally, the minimal Root Mean Square Error (RMSE) values of 1.291 and 1.550 for N2 and H2 predictions respectively underscore the precision of DTAH, establishing it as a suitable choice for practical real-world applications.

Modeling the Operating Conditions of Electric Power Systems Feeding DC and AC Traction Substations

Modeling the Operating Conditions of Electric Power Systems Feeding DC and AC Traction Substations

A low voltage load balancing distribution method considering street information and V2G technology application

The low-voltage distribution network (LVDN) is the final stage in delivering electric energy from power plants to consumers, and its operational condition greatly impacts many power users. While medium-voltage and high-voltage distribution networks can be managed through intelligent digital systems, load imbalance issues in LVDNs often rely on planners’ experience, leading to significant limitations. With advancements in electric vehicle (EV) charging technology and vehicle-to-grid (V2G) technology, where EVs act as distributed energy storage units, bidirectional energy exchange between vehicles and the grid can now contribute to LVDN operation. This paper proposes a low-voltage load distribution planning method that integrates street information and V2G technology. A two-stage stochastic programming mixed-integer model is developed to tackle load imbalance in LVDNs, with the planning scheme derived from solving this model. A case study is presented to verify the effectiveness of the method, demonstrating that incorporating V2G technology enhances load distribution accuracy and reduces reliance on manual planning, improving network stability and operational efficiency.

A Demonstration of the Risk-Informed NEI 18-04 Design Evaluation Model for the Modular High-Temperature Gas Reactor

Several advanced reactor designs are now under active development in the United States and elsewhere, promising sustainable solutions to the growing world energy needs. The designs currently being considered are quite diverse and different from the more established light water reactor technology that has dominated the operating commercial nuclear landscape. While advanced reactor concepts were first explored in the dawn of the nuclear age, they are now being reconsidered under the light of modern needs, and specifically, for their flexible operating conditions and inherent safety characteristics. In response, the U.S. Nuclear Regulatory Commission staff is moving forward with development of 10 CFR Part 53 rulemaking, which is a more risk-informed, technology-agnostic framework for licensing and regulating such new designs. The nuclear industry response to this regulatory initiative resulted in the technical report by the Nuclear Energy Institute, NEI 18-04 Revision 1, which provides an implementation roadmap of the risk-informed approach when defining the safety case for a new plant design. The implementation of this safety case may be a nontrivial exercise for an actual reactor design. This paper provides a demonstration of performing such an analysis for a representative advanced reactor. Public information from the General Atomics high-temperature gas reactor design was considered in this demonstration. The analysis workflow was facilitated with the FPoliSolutions’ proprietary Risk-Informed System Engineering (RISE) digital platform, a product that was presented in previous publications. RISE is one application of FPoli’s enterprise digital platform, which was created to facilitate orchestration of complex workflows leveraging recent technologies developed at national laboratories, such as Idaho National Laboratory’s RAVEN and EMRALD frameworks. The analysis described in the paper includes the selection and classifications of events, the integration of probabilistic risk analysis artifacts, and event modeling simulations for consequence evaluations. The results are then used for system, structures, and components safety classification and a synthesis of the safety case for the design in line with the frequency-consequence targets presented in NEI 18-04. The purpose of the analysis, as framed in RISE, is to readily produce outputs and views that can aid users and regulators in making risk-informed decisions to demonstrate their plant safety case.

Evaluation and Upscaling of Impregnated La0.20Sr0.25Ca0.45TiO3 Fuel Electrodes for Solid Oxide Electrolysis Cells

Abstract Recent research into Rh and Ce0.80Gd0.20O1.90-impregnated La0.20Sr0.25Ca0.45TiO3 fuel electrodes for solid oxide fuel cells has demonstrated the high-stability of these material sets to a variety of harsh operating conditions at small scales (1 cm2 active area button cells), as well as commercial scales (100 cm2 cells) in short stacks (5 cells) and full micro-combined heat and power systems (60 cells). In this work, the authors present a comprehensive evaluation of the ability of these novel titanate-based materials to function as fuel electrodes in solid oxide electrolysis cells (SOECs). Short-term and durability testing of button cell scale SOECs highlighted the limited stability of lanthanum strontium manganite-based air electrodes, under CO2 and steam electrolysis conditions, with lanthanum strontium cobaltite ferrite-based air electrodes offering improved degradation characteristics. Upscaling of this optimized cell chemistry to a 16 cm2 active area SOEC and testing under CO2, CO2/H2O and H2O electrolysis conditions demonstrated encouraging performance over a period of ~600 hours, with stable co-electrolysis performance at ~−7.5 A at 1.47 V for the first 100 hours.

Environmentally Acceptable Lubricants for Stern Tube Application: Shear Stability and Friction Factor

Stern tube lubricants are essential in maritime operations, safeguarding ship propeller shafts from wear and corrosion while ensuring efficient propulsion. Their role in reducing friction and maintaining system integrity is critical. With growing environmental concerns, the adoption of environmentally acceptable lubricants (EALs) for stern tubes has gained importance, balancing operational performance with environmental protection. This study investigates the rheological and tribological properties of EALs formulated for ship propeller stern tube applications. The primary focus is on comparing these EALs with conventional mineral oils to assess their suitability in marine environments. EALs are increasingly favored due to their biodegradability and reduced environmental impact. Key parameters such as shear stability, friction factor, and temperature dependency were evaluated using a range of experimental methods including rotational viscometry and tribological analysis. The results indicate that the newly formulated EALs based on synthetic esters exhibit the highest viscosity index, a higher range of shear stability, and lower friction factors, compared to commercially available mineral oils, especially under varying operational conditions. These findings contribute to the ongoing efforts to promote eco-friendly lubricants in maritime industries, aligning with global environmental protection initiatives.

An Evaluation Modeling Study of Thermal Runaway in Li-Ion Batteries Based on Operation Environments in an Energy Storage System

According to the green growth and carbon-neutral policy in Korea, the installation of large-capacity ESSs is rapidly being increased, but a total number of 50 ESS fire cases have occurred since the end of 2023. ESSs are typically composed of series-parallel connections with numerous Li-ion batteries, and when the temperature of a deteriorated cell increases due to thermal, electrical, and mechanical stress, thermal runaway can occur due to additional heat generated by an internal chemical reaction. Here, an internal chemical reaction in a Li-ion battery results in the different characteristics on the decomposition reaction and heat release depending on the operation conditions in the ESS, such as the rising temperature rate, convective heat transfer coefficient, and C-rate of charging and discharging. Therefore, this paper presents mathematical equations and modeling of thermal runaway, composed of the heating device section, heat release section by chemical reaction, chemical reaction section at the SEI layer, chemical reaction section between the negative and positive electrodes and solvents, and chemical reaction section at the electrolyte by itself, based on MATLAB/SIMULINK (2022), which were validated by a thermal runaway test device. From the simulation and test results based on the proposed simulation modeling and test device according to the operation conditions in ESSs, it was found that the proposed modeling is an effective and reliable tool to evaluate the processing characteristics of thermal runaway because the occurrence time intervals and maximum temperatures had almost the same values in both the test device and simulation modeling. Accordingly, it was confirmed that the rising temperature rate and the convective heat transfer coefficient were more critical in the thermal runaway than the C-rate of charging and discharging.

Enhancing quality in Lot reception: A comparative analysis of innovative attribute acceptance sampling plans

Purpose: This study aims to enhance production quality by applying Quality Control (QC) principles through acceptance sampling, specifically analyzing the efficacy of attribute acceptance sampling plans in final lot receptions.Design/methodology/approach: Through a comprehensive review and critical evaluation of various sampling methodologies found in literature, this paper assesses their efficiency under distinct administrative and operational conditions. It emphasizes the comparison of different attribute acceptance sampling plans by examining variations in parameters and key performance indicators, such as Average Outgoing Quality (AOQ) and inspection time allocation percentage. Furthermore, it proposes a model for Continuous Sampling Plans (CSP) to evaluate these plans' performance in response to operational characteristic variations.Findings: The analysis reveals that the selected methodologies significantly aid in decision-making processes for lot acceptance, utilizing non-conforming rates depicted by the Average Quality Level (AQL). This provides a robust framework for improving Quality Control strategies, demonstrating the potential of these methodologies to optimize production quality through strategic lot acceptance.Practical implications: This paper outlines a practical approach for industry practitioners to enhance decision-making in lot acceptance, offering a method to balance quality control with operational efficiency effectively.Originality/value: By comparing a wide range of attribute acceptance sampling plans and introducing a novel CSP model, this research contributes valuable insights into the optimization of QC strategies. It offers a unique perspective on enhancing production quality, marking a significant advancement in the field of Quality Control and management.

Analysis of Thermo-Acoustic Instabilities Induced by Hydrogen Swirling Flames

Abstract A considerable research effort has been concerned combustion dynamics of systems fed with hydrocarbon fuels. The case of pure hydrogen/air flames deserves to be specifically considered because hydrogen is highly reactive, has a tendency to develop thermo-diffusive instabilities, is envisaged in many future applications, most notably in gas turbines, and is less well documented. Thermo-acoustic instabilities of pure hydrogen flames are here investigated in a configuration where hydrogen is injected in-crossflow in a swirling stream of air. The study is focused on operating conditions that lead to oscillatory regimes. Using Abel-transformed phase-averaged images of OH* emission and visible light emission in burnt gases, it is shown that the OH* signal evolves approximately in phase with the heat release rate. This signal is then used to determine the local Rayleigh source term that feeds acoustic energy in the oscillation. The contributions of this term are examined using a space–time analysis based on an integration of the source term in the transverse direction. This procedure allows a detailed analysis of the processes that contribute to the acoustic energy in the system, showing, in particular, that a strong positive addition of acoustic energy results from a roll-up of the flame tip and from the quick cyclic back propagation of the flame to the injector tip. A global integration of the Rayleigh source term is then used together with a volume-integrated acoustic energy to estimate the growth rate associated with these driving processes and estimate the damping rate. A special experimental method is then exploited to determine the effective growth rate of the instability. The system allowing a sweep in frequency, self-sustained instabilities obtained at different frequencies are used to extract the specific instability frequency band of the burner. Finally, the flame is externally forced in order to measure its flame-describing function.

Optimization of the Design of a Greenhouse LED Luminaire with Immersion Cooling

Modern agriculture, with the use of artificial lighting, requires high-intensity LED luminaires with compact dimensions. In this regard, new approaches to the design of LED luminaires using both new materials and technical solutions have been considered. The theoretical evaluation of the influence of different materials on the efficiency of removal of thermal energy from LEDs was shown. A new material PMS-5 is proposed and evaluated as an immersion liquid, which can be used as an effective heat sink in the lower part of the luminaire up to the level of LEDs located in the top light LED luminaires. The proposed polymethylsiloxane PMS-5 liquid has more than twice the thermal conductivity (0.167 W/(m·K)) of HFE7200 and NS15 liquids used in immersion-cooled LED luminaires. Based on the theoretical evaluation, the requirements for parameters, such as metal profile area, immersion liquid volume, wall thickness area, and external area of the cylinder, are highlighted and shown. The noted parameters have a key role in the design of an efficient top light LED luminaire. It has been shown that the design of the metal profile significantly affects the efficiency of the removal of thermal energy from LEDs and it is necessary to use specialized profiles optimized for the diameter of the LED luminaire cylinder. A number of LED luminaire designs were proposed, depending on the thermal properties of the construction materials, technical and economic performance, as well as actual operating and installation conditions. The analysis of the presented theoretical evaluations allowed overlay of the design basis of LED luminaires within the presented concept and top light.

Investigation of the Sigma Approximation Technique for the Solution of the Time Spectral Equation System

Abstract The time spectral method is commonly utilized to analyze periodic unsteady flows within turbomachines. However, the time spectral solutions in regions with large temporal and spatial gradients, such as wakes, shocks, and boundary layers, can be plagued with unphysical oscillations, known as the Gibbs phenomenon. This paper presents an investigation into the sigma approximation technique, which is capable of significantly attenuating the Gibbs phenomenon by dampening high-frequency nonlinear components in the time spectral solutions. However, the optimal combination of the sigma factors remains to be ascertained considering the trade-off between the accuracy of solutions and the reduction of unphysical oscillations. In this study, a two-row compressor configuration is first selected, and numerical simulations are performed to evaluate the efficacy of this technique under near peak-efficiency and near-stall operating conditions. It is found that Gibbs-type unphysical oscillations can be effectively mitigated without notably compromising solution accuracy through an optimal combination of sigma factors. The NASA Stage 35 case study further verifies the effectiveness of the proposed optimal sigma factor combination in preserving the accuracy of time spectral solutions based on the data from test rig. Moreover, the von Neumann analysis reveals that the sigma approximation technique can enhance the numerical stability of the time spectral equation system, thereby allowing the use of aggressive numerical parameters to accelerate convergence. The stability analysis results are verified by a two-dimension bump under two different flow conditions and further assessed using the two-row compressor.

Catalytic Potential-Guided Design of Multi-Enzymatic System for DHA Production from Glycerol

The growing demand for sustainable chemical production has spurred significant interest in biocatalysis. This study is framed within the biocatalytic production of 1,3-dihydroxyacetone (DHA) from glycerol, a byproduct of biodiesel manufacturing. The main goal of this study is to address the challenge of identifying the optimal operating conditions. To achieve this, catalytic potential, a lumped parameter that considers both the activity and stability of immobilized biocatalysts, was used to guide the design of a multi-enzymatic system. The multi-enzymatic system comprises glycerol dehydrogenase (GlyDH) and NADH oxidase (NOX). The enzymatic oxidation of glycerol to DHA catalyzed by GlyDH requires the cofactor NAD+. The integration of NOX into a one-pot reactor allows for the in situ regeneration of NAD+, enhancing the overall efficiency of the process. Furthermore, immobilization on Ni+2 agarose chelated supports, combined with post-immobilization modifications (glutaraldehyde crosslinking for GlyDH), significantly improved the stability and activity of both enzymes. The catalytic potential enabled the identification of the optimal operating conditions, which were 30 °C and pH 7.5, favoring NOX stability. This work establishes a framework for the rational design and optimization of multi-enzymatic systems. It highlights the crucial interplay between individual enzyme properties and process conditions to achieve efficient and sustainable biocatalytic transformations.

An Experimental Study on the Effect of Intake Pressure on a Natural Gas-Diesel Dual-Fuel Engine

Abstract Natural gas-diesel dual-fuel (NDDF) combustion can be a viable method to reduce diesel usage in compression ignition (CI) internal combustion engines. Potential benefits of NDDF engines in comparison to conventional diesel engines include decreases in soot and carbon dioxide emissions. This study focuses on the effect of intake pressure on a dual-fuel engine with intake port injected natural gas (NG) and direct injected diesel at two engine operation conditions – low load-high speed and high load-low speed. The research work was performed on a heavy-duty, single-cylinder engine at a NG-diesel energy ratio of approximately 3:1. The results show that when the intake pressure was increased, the indicated thermal efficiency (ITE) increased for diesel combustion. The trend was similar at the high load-low speed condition but opposite at the low load-high speed condition for NDDF. ITEs of diesel combustion were generally higher than NDDF combustion due to higher unburned hydrocarbon (HC) emissions associated with the latter. For low load-high speed dual-fuel combustion, increasing intake pressure increased the HC and soot emissions, but decreased the nitrogen oxides (NOx) emissions. For high load-low speed case, increasing intake pressure caused the HC emissions to increase and the NOx and soot emissions to decrease. In-cylinder temperature measured at the tip of the diesel injector showed that the injector tip temperatures were higher for NDDF cases compared to diesel cases. These temperatures could be correlated with the combustion phasing and NOx emissions.

Validation of a Methodology To Assess The Flutter Limit Cycle Oscillation Amplitude of Low-Pressure Turbine Bladed-Disks - Part II: Rotational Speed Effects

Abstract The effect of the operating conditions on the vibration amplitude trends of an isolated low-pressure turbine rotor is described. The study utilizes an analytical model correlating the aerodynamic and dry-friction work introduced in Part I of the paper. In this Part II, the analysis has been extended to incorporate the influence of rotational speed. The force distribution and the penetration length of the fir-tree contact surfaces are key parameters within the heuristic micro-slip model used to characterize the friction forces. These parameters change with rotational speed, consequently influencing the dry-friction work involved in the process. The model is closed with numerical simulations to compute the aerodynamic damping, and it is compared against experimental data gathered from the experimental campaign detailed in Part I. The results demonstrate a significant impact of the shaft speed on flutter vibration amplitude. The vibration amplitude has been observed to reach a maximum near the on-design conditions. The analytical model can correctly capture this trend indicating that the essential physics is retained in it. Nonlinear friction, mistuning and 3D unsteady aerodynamics have shown to play a predominant role to explain the change of vibration amplitude with the shaft speed.

A position-free control strategy in the full speed domain based on an electro-hydraulic pump

The electric plunger hydraulic pump plays a crucial role in hydraulic transmission technology by integrating an electric motor and a hydraulic pump. The main objectives in designing such devices are to improve efficiency, achieve miniaturization, and promote environmental sustainability. This paper introduces a speed control strategy for an electric hydraulic pump that operates across its entire speed range without relying on position sensor feedback. We begin by establishing the overall model of the electric hydraulic pump and motor characteristics under different operating conditions. Next, we employ a high-frequency injection control method to enable the electric hydraulic pump to start at zero-speed or low-speed states. Additionally, the optimized extended Kalman filtering control method enhances the robustness and tracking performance of the electric hydraulic pump in the medium to high-speed range. Finally, considering the motor characteristics under different operating conditions, we achieve sensorless control of the electric hydraulic pump across the full speed range. Our proposed control strategy provides a promising solution for the control of electric plunger hydraulic pumps, with widespread industrial applications.

New characterization models for macroscopic chemical-hydrodynamic behavior of catalytic cracking riser-reactor with interactive patterns of severe operating conditions using CFD calculations

BackgroundFCC is the core of refining technologies for production of high-valued chemicals including, light olefins, and fuels. Global capacity of catalytic cracking unites is projected to grow from 14.4 to 15.8 million barrels per day from 2022 to 2026. Moreover, global production of 57 % ethylene, 42 % propylene and 69 % butylene is based on deep/fluid catalytic cracking. Therefore, optimization of catalytic cracking process is our indispensable industrial approach. MethodsThis study is optimization of industrial catalytic cracking unit for maximizing the yield of light gases, gasoline and gasoil conversion using CFD calculations. Hydrodynamic behavior and performance of the riser-reactor was investigated at severe operating conditions, including feed temperature, catalyst temperature and catalyst to oil ratio (CTO) in the range of 788–903 K, 813–1013 K and 6–18, respectively. New characterization models were proposed for macroscopic chemical-dynamic behavior of the process. Models validated with ANOVA analysis, RSM methodology. Significant findingsResults showed that the maximum products yield and gasoil conversion occur between 4 and 8 s. It was obtained that the maximum yield of nearly 12 wt% light gases, 38–39 wt% gasoline and 54 % conversion is possible for this geometry of industrial unit via optimization of operating conditions. Coefficients of obtained models and interactive patterns of operating conditions showed that CTO is the most influential parameter on riser-reactor performance.