Dynamic modelling and simulation of a heated brine spray system

This paper discusses dynamic modeling and simulation of distributed static compensators (DSTATCOM) in system impact studies involving renewable applications, e.g., wind or solar power plants. Two dynamic simulation models of the DTSTACOM are presented and discussed. Dynamic simulations are presented to show that a reactive compensation system (RCS) assembled with the DSTATCOM as a master controller complies with reactive power, voltage control, and low voltage ride-though requirements for a wind power plant. Benchmark and real system models integrate the mechanically switched capacitors and the wind turbine generator reactive power capability into the total RCS system. The reactive characteristics of the DSTATCOM are also discussed.

<div class="htmlview paragraph">The purpose of dynamic modeling and simulation of Advanced Life Support (ALS) systems is to help design them. Static steady state systems analysis provides basic information and is necessary to guide dynamic modeling, but static analysis is not sufficient to design and compare systems. ALS systems must respond to external input variations and internal off-nominal behavior. Buffer sizing, resupply scheduling, failure response, and control system design are aspects of dynamic system design. We develop two dynamic mass flow models and use them in simulations to evaluate systems issues, optimize designs, and make system design trades. One model is of nitrogen leakage in the space station, the other is of a waste processor failure in a regenerative life support system.</div> <div class="htmlview paragraph">Most systems analyses are concerned with optimizing the cost/benefit of a system at its nominal steady-state operating point. ALS analysis must go beyond the static steady state to include dynamic system design. All life support systems exhibit behavior that varies over time. ALS systems must respond to equipment operating cycles, repair schedules, and occasional off-nominal behavior or malfunctions. Biological components, such as bioreactors, composters, and food plant growth chambers, usually have operating cycles or other complex time behavior. Buffer sizes, material stocks, and resupply rates determine dynamic system behavior and directly affect system mass and cost. Dynamic simulation is needed to avoid the extremes of costly over-design of buffers and material reserves or system failure due to insufficient buffers and lack of stored material.</div>

Dynamic simulation is a powerful tool for chemical process optimizing design, which gives an intuitionistic sight for engineer to understand chemical process and analyzing process design. In this work, a dynamic simulation model for the full flow isopropyl benzene plant is presented. The dynamic model is based on detailed configuration of equipment data from a 300,000 t/a isopropyl benzene plant. It was discovered that the benzene column has the problem of pressure fluctuation. The cause of this fluctuation was analysed and the solutions to solve problem were presented by using dynamic model. Emergency condition, and partial power failure, both were considered for isopropyl benzene column design. The dynamic relieving rate was calculated, and the results compared with that calculated from conventional method. In order to avoiding the relieving rate, high integrated protective system (HIPPS) was applied to the dynamic model. The results shown that (1) The reason of benzene column pressure fluctuation is that the solubility of propane in condensate is sensitive to process parameters. A pressure control scheme with tuned PID parameters was proved in good performance; (2) The relieving rate of isopropyl benzene column calculated from dynamic model decrease 65% compared with that of conventional method; (3) The relieving rate of isopropyl benzene column was cut to zero by using HIPPS.

The production process of robot castings mainly includes processes such as robot core taking, core assembly, core setting, dipping, pouring, sand casting, polishing, and cleaning. The handling process involves every process of the casting production line and is one of the key processes of the casting production line. For the 6-axis robot used for handling, the kinematics model of the robot is carried out according to the improved DH parameter method, and the dynamic model of the robot is established by using Newton-Euler equation and Lagrangian equation respectively. Secondly, according to the requirements of casting handling technology, the motion trajectory is planned according to the established kinematics model and dynamics model, and the dynamic simulation is carried out with MATLAB. The joint torques of the robot dynamic models established by the two methods are very close, which verifies the correctness of the dynamic model.

Steel cord conveyor belts are widely used in long-distance transportation of various materials. The steel cord belt is composed of rubber and steel cord core, exhibiting excellent viscoelasticity and complex dynamic characteristics during operation. The existing static elastic modulus cannot accurately reflect the real dynamic properties of the conveyor belt. In this paper, based on the catenary theory, the formula for the dynamic elastic modulus of the conveyor belt is derived by introducing the sag and elastic deformation of the steel cord conveyor belt on the basis of the static elastic modulus. The dynamic modeling of the steel cord conveyor belt is carried out using rigid belt block element + flexible beam method. Then, the RecurDyn software is used to establish the dynamic simulation system of the belt conveyor and conduct simulations, which are validated through a test bench. The results show that dynamics simulation based on the dynamic elastic modulus is closer to the real dynamic characteristics of the belt conveyor. Finally, the dynamic characteristics of belt conveyors under different start-up times, different start-up speeds, and idler spacing are analyzed using this modeling and simulation method. The results demonstrate that the dynamic elastic modulus can accurately reflect the real dynamic properties of the conveyor belt, providing a more accurate dynamic modeling and simulation method for the design of belt conveyors.

Servo electric cylinders have been widely adopted in high-performance linear drive applications such as aerospace systems, robotic servo systems, medical equipment, advanced manufacturing, precision testing, and high-end equipment due to their advantages, including high cleanliness, compact structure, high transmission efficiency, and ease of achieving precise control. However, under complex operating conditions, system performance is influenced not only by control strategies but also closely related to factors such as friction, clearance, transmission flexibility, structural vibrations, and modeling accuracy. This paper reviews mainstream control strategies and dynamic simulation methods for servo electric cylinders, providing structured analysis and systematic evaluation of representative research. In terms of control strategies, key approaches, including classical PID control, robust nonlinear control, intelligent and learning-based control, and active disturbance rejection control, are discussed, with comparative analysis of their characteristics and limitations in tracking accuracy, robustness, adaptability, and engineering feasibility. Regarding dynamic modeling and simulation, methods such as multibody dynamics, finite element analysis, rigid-flexible coupling, and multi-domain collaborative simulation are reviewed, examining their applicability in nonlinear mechanism characterization, local structural response assessment, and high-fidelity system modeling. Current research indicates that servo cylinder control is evolving from single-method improvements toward integrated and composite approaches, while dynamic modeling has progressed from low-order simplified analyses to system-level, multi-level, and high-fidelity descriptions. Existing studies still face challenges, including insufficient unified evaluation criteria, inadequate cross-method comparisons, and insufficient integration between control design and high-fidelity models. Future research should focus on enhancing control-model co-design, experimental validation under complex conditions, and system-level optimization oriented toward intelligent and high-reliability systems.

In order to further reduce the incisions of laparoscopic surgery and the possibility of infection, the organic combination of single-incision laparoscopic surgery (SILS) and robotics has made the degree of minimally invasive surgery further improved. A new 5-DOF single-incision laparoscopic surgery robot was designed based on Axiomatic Design Theory, whose structure consisting of the movement mechanism, the endoscope and the position and pose adjustment mechanism. The robot parts are connected in series and parallel, allowing a pivotal motion of the endoscope in the center of the robot for realizing the incision. In order to achieve a performance optimization and a dynamic control of the single-incision laparoscopic surgical robot, the kinematics and dynamic modeling and dynamic stiffness analysis of the robot are especially important. The forward kinematics equation, inverse kinematics equation and Jacobian matrix of the SILS robot are derived based on D-H method and geometric method, and the kinematics numerical simulation is carried out by Matlab. The dynamic equation of the robot is derived by Kane method. Subsequently, a numerical simulation of the robot dynamics equation is performed, with its virtual prototype utilized to set the motion plan of the robot mechanism. After robot’s dynamic simulation, the numerical changes of the driving force and torque for each robot’s moving mechanism are obtained. The performed simulation results further verify the correctness of the established robot’s dynamic model. Finally, utilizing the above methods, the dynamic stiffness model and evaluation index of the robot are determined, and the dynamic stiffness of the robot is analyzed and evaluated. The results of the kinematics, dynamic and stiffness analysis of the SILS robot further validate that the 5-DOF SILS robot has a reasonable structure, motion and sufficient stability to meet the needs of single-incision laparoscopic surgery.

A dynamic dehumidifier model for simulations and control of liquid desiccant hybrid air conditioning systems

Modeling of CSTR and SPR small-scale isothermal reactors for heavy oil hydrocracking and hydrotreating

In view of mechanism principles, dynamic model of rectifying tower, one of the most important unit operations in chemical industry, was built in this work, and abnormal simulation for some typical faults was performed. The constant-volume flash model was proposed and utilized to model each distillation stage. During the modeling procedure, MATLAB software was used to code the model and execute dynamic simulation. The final steady-state result thus obtained was compared with the one from PRO/II to verify the correctness and accuracy of the model. Based on the above model, we choose three kinds of fault, that is, change of reflux ratio, feed thermal condition, and bottom heating quantity. Having the corresponding fault parameters set in the model, dynamic simulation is utilized to demonstrate consequences which these faults cause, thus it is possible to investigate fault occurrence behavior and facilitate early stage detection and control of abnormal event.

Dynamic modelling and simulation of the biscuit baking oven process

An integrated dynamic modelling and simulation system for analysis of particulate processes

The dynamic model of wire rope is established by discrete beam finite elements and the relative nodal displacements method. The dynamic simulation model of wire rope involving contact with a winch drum is presented based on finite element method and the flexible multi-body dynamics theory considering large deformation motion by putting the contact force between the wire rope and drum. Simulation results show that the dynamic model of wire rope with contact can be applied in the nonlinear dynamic analysis of flexible body transmission and realized the visualization dynamic simulation.

Conventional subsurface reservoir candidates for CO2 Sequestration are usually just deeper than 800 m to ensure CO2 is injected at supercritical state, typically these are shallow, gently dipped, low pressure saline aquifer or completely depleted and abandoned hydrocarbon reservoirs. However, in this study within the western desert of Egypt, none of the reservoirs are abandoned and the saline aquifers below 800 m are too tight with no injectivity. So, the only way was to target ultra deep saline aquifer deeper than 3 km with virgin pressure of more than 5000 psi. These ultra deep aquifers are usually highly titled, surrounded by major faults, and highly saline and those factors act against the typical trapping mechanisms for CO2 sequestration such as structural trapping, residual trapping and CO2 solubility. In this case study, we present a novel approach that relies on innovative technology to solve this unconventional challenge to sequester 0.5 Mton CO2 per annum in ultra deep saline aquifers and open the pathway for carbon storage in unconventional storage sites. The applied approach is divided into three phases. Phase one is site screening to automatically identify the best possible sites for CO2 storage based on a scientific scorecard. Then in Phase two, dynamic simulation of the injected supercritical CO2 plume movement within the formations while honoring advanced trapping mechanisms such as CO2 trapping due to residual trapping and dissolution in saline water. Then the dynamic reservoir simulation models are fully coupled to 3D geomechanics models to study the impact of the injection on the well integrity, cap rock integrity as well as fault reactivation and integrity. Finally in Phase 3, an economical surface facility configuration and pipelining scenarios that fit the subsurface sites’ requirements. It was concluded through an ensemble of geological scenarios that safe CO2 trapping mechanism can be increased by 30% using a time and rate managed sequential injection scheme starting from the bottom of the formation and upwards. the dynamic simulation results show that this technique helps increasing the contact area with the saline water while leveraging high pressure to overcome low solubility in highly saline water and creating convective water density currents, hence increasing CO2 solubility in water as well as residual trapping of CO2 even in structurally marginal sites. The followed scientific approach unlocked the potential for CO2 sequestration in ultra deep saline aquifers within the western desert to be deployed for a long-term and safe sequestration of CO2 while accounting for the complex subsurface structure to pave the way for future successful CCS projects in similar environments.

The swath-plate engine is an engine with high pressure air as working medium, and it is designed to meet the underwater launch. In order to explore the performance of the engine, the dynamic model is built by using the method of Kane on the basis of the kinematics and dynamic analysis of the main parts of the engine such as the pistons and links, etc. The simulation of the work process of the engine is realized by the use of the simulation program based on the dynamic model. The prototype engine is tested on the experiment system. The comparison of the experimental results and simulation results show that the dynamic simulation model is basically correct and can be used to optimize the engine design.