Weirong Hong

Zhejiang University | ZJU · Department of Chemical and Biological Engineering

Autonomous vehicles have gained popularity over the past few years. In this paper, an MPC-based lateral motion controller for autonomous vehicles through serially cascade discretization method is developed. A single discretization method in the entire prediction horizon is usually adopted in MPC. This article seeks to cascade discretization methods...

Dynamic optimization constrained by partial differential equations (PDE) involves the state distribution on space, and can generate improved operational policies compared to ODE-constrained dynamic optimization. With the help of space-time orthogonal collocation on finite elements (ST-OCFE) which can guarantee relatively high accuracy in both space...

Autonomous vehicles have gained popularity over the past few years. In this paper, we present a nonlinear model predictive control approach for autonomous vehicles to follow the desired path in various driving environments. Instead of utilizing Euler discretization method which is common in the literature related to MPC-based path tracking, our for...

A newly developed flat-chip solid oxide fuel cell (FCSOFC) shows advantages for its improved tolerance towards fast start-up and thermal shock, which makes it suitable to serve as portable or backup power supplier. In this study, a three-dimensional electro-chemo-thermo coupled numerical model is developed to analyze the factors limiting the power...

In this study, the effects of residual stress induced by three different cooling methods during heat treatment on the crack propagation behaviour of the GH4169 disc were investigated. Different levels of stress fields were induced to the specially designed discs by using air cooling (AC), air jetting cooling (AJC) and water quenching (WQ) methods a...

As a novel renewable energy cell type, flat tubular solid oxide fuel cell (FT-SOFC) has the advantages of easy sealing, low resistance, and better stability. Optimization for fuel cell output performance was traditionally implemented through the combination and comparison of a set of experiments or simulations. Optimization algorithms are rarely us...

Labyrinth-honeycomb seals are a state-of-the-art sealing technology commonly used in aero-engine interstage seal. The undesirable severe rub between the seal fins and the honeycomb due to the clearance change may induce the cracking of the seal fins. A pervious study investigated the wear of the seal fins at different radial incursion rates. Howeve...

Labyrinth seals as a noncontact sealing technology are widely used in aero-engine. To improve the efficiency of the aero-engine, the clearance between the rotor and stator must be as small as possible. However, the change of the clearance between the rotor and stator because of thermal expansion, vibration, mechanical loading may lead to undesirabl...

To investigate the containment characteristics and mechanisms of axial compressor blade and casing in turboshaft engine, experimental and simulation research is conducted on Titanium alloy axial compressor blades and stainless steel simulator casings in this paper. Experiments for four thicknesses (from 0.8 mm to 1.4 mm) of casings are presented on...

Abradable seal rubber has been widely used in aero-engine fans to improve their efficiency by reducing the clearance between rotating and stationary components. To investigate the high-speed scraping behavior between a vulcanized silicone rubber and a Ti-6Al-4V fan blade and evaluate the abradable performance of seal rubber, abrasion tests were con...

To investigate the containment mechanism of the soft wall casing, a series of tests were conducted on a high-speed spin tester. A special testing method using spin tester for the containment of soft wall casing is developed. The subscale casing was fabricated by wrapping multiple layers of Kevlar49 plain woven fabric around the inner thin aluminum...

To study the effects of multi-blade interaction on the blade containment capability of the aero-engine casing, series of blade containment tests and the corresponding numerical analysis for the fan and the turbine components are carried out. Numerical models are validated through the correlation of the numerical results with the experimental data....

In reciprocating compressors, partial unloading stepless capacity regulation causes the power consumption to reduce in proportion to the decrease in capacity. To enable the widespread application of this method, it is necessary to analyse the changes in the mechanical status of a reciprocating compressor while its capacity is being regulated. This...

Two dimensional (2D) triaxial braided composites have been successfully used in aero-engine fan containment system for weight reduction. In the current study, blade containment tests were conducted on high-speed rotor spin tester to investigate the containment process and failure mechanisms of the composite casing. The composite casing was fabricat...

Film flow is often employed to improve the mass transfer between gas and liquid in chemical industry application. Corrugations on packing surface are used to alter the flow characteristics of liquid film to enhance the mass transfer efficiency. In this investigation, film flow over three dimensional corrugations was simulated with numerical method....

The rated capacity of reciprocating compressor tends to be higher than the level needed, so the capacity regulation needs to be implemented to save unnecessary energy waste. Among the methods for reciprocating compressor capacity regulation, holding the suction valves open in partial stroke is a widely used method for its economy, full-range and ea...

The packing structure and surface geometry can change the flow pattern, and has significant influence on the mass transfer between liquid film and gas phase in packing column of chemical industry. It is necessary to investigate the flow pattern and factors that affect the tower efficiency. The Packing with different structure including triangular c...

Liquid film flow over triangular corrugations is investigated by simulations and experiments. The volume of fluid (VOF) method is used to track the free surface between the liquid and gas in computational fluid dynamics (CFD) simulations. In the experiments, a sCMOS camera is applied to capture the film flow in a channel. The comparison of the resu...

Chromatographic separation processes such as simulated moving bed (SMB) are widely used in the petrochemical, fine chemical, sugar, and pharmaceutical industries. Their separation efficiency can be improved by optimizing the components’ adsorptivity in the different unit sections through, e.g., the use of solvent, temperature, or PH gradients. In t...

Thick film flow in a narrow channel is investigated by simulations and experiments. The influence of obstacle and corrugations on liquid film flow is studied in simulations. LIF (light induced fluorescence) method is applied to visualize the flow field close to the substrate in the experiments. With the validated 3-D simulations, numerical investig...

The existing researches of stepless capacity regulation system by depressing the suction valve for reciprocation compressor always adopt hypothesis that the compressor valves are open or close instantaneously, the valve dynamic has not been taken account into thermal cycle computation, the influence of capacity regulation system on suction valves d...

The structure of the plate rib roof can’t meet the need of the constantly enlarging storage tanks, thus more steel/aluminum net shell roofs have been used on the large storage tanks. The bearing between the roof and the tank wall is a key component, because it directly affects the strength and stability of the net shell roof. In this paper, a new t...

A comparison of arithmetic operations of two dynamic process optimization approaches called quasi-sequential approach and reduced Sequential Quadratic Programming (rSQP) simultaneous approach with respect to equality constrained optimization problems is presented. Through the detail comparison of arithmetic operations, it is concluded that the aver...

We present an improved quasi-sequential approach to large-scale dynamic process optimization. This new approach incorporates the quasi-sequential approach with the interior point method to handle inequality constraints. In this way the eventual optimization problem to be solved becomes a NLP without constraints. Mathematical derivations and computa...

The present article focuses on a stepless capacity regulation system for reciprocating compressors in the capacity range between 0 and 100 per cent. This system is based on the so-called reverse flow regulation principle. The principle works by reversing part of the total gas that has been taken into the cylinder by conveying it back to the suction...

The electric conductive polymer composites, which were made of carbon black particles through dispersing in mixtures of polyacrylonitrile (PAN)/nylon6 (PA6), were prepared in a Haake Thermo-mixer. The morphology, conductivity, thermorheology properties and their relationships were studied. Microphase separations and partial miscibility were confirm...

The method that depresses the suction valves in the partial compression stroke to realize the stepless capacity regulation for reciprocating compressor makes the compressor power consumption reduce along with the decreasing of capacity. However, the operation condition of suction valves is greatly changed by this method and it is necessary to analy...

Zum Vol. I von: Computer science meets automation: 52. IWK, Internationales Wissenschaftliches Kolloquium ; proceedings ; 10 - 13 September 2007 Zum Vol. II von: Computer science meets automation: 52. IWK, Internationales Wissenschaftliches Kolloquium ; proceedings ; 10 - 13 September 2007

A novel sequential approach for solving dynamic optimization problems containing path constraints on state variables is presented and its performance analyzed. As in the simultaneous approach, we discretize both state and control variables using collocation on finite elements, so that path constraints can be guaranteed inside each element. The stat...

Unlike steady-state optimization and linear model predictive control, dynamic optimization and nonlinear model predictive control is underway to industry application. This paper discusses the implementation issues of two-level control strategy integrated dynamic real-time optimization and nonlinear model predictive control of a heat-integrated dist...

Because of their higher efficiency of energy utilization, heat-integrated distillation columns are widely used in the chemical industry. The strong coupling of columns due to the heat integration leads to difficulties for control and optimization. This work concerns the dynamic optimization of heat-integrated columns, because such processes are oft...