scholarly journals Development of a Model for Stormwater Runoff Prediction on Vertical Test Panels Coated with Plaster and Mortar

Water ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2593
Author(s):  
Pablo Vega-Garcia ◽  
Regina Schwerd ◽  
Christian Scherer ◽  
Christoph Schwitalla ◽  
Brigitte Helmreich
Keyword(s):  
Stormwater Runoff ◽  
Construction Materials ◽  
Sampling Period ◽  
Analytical Models ◽  
New Model ◽  
Fraunhofer Institute ◽  
Building Facades ◽  
Simulation Results ◽  
Building Physics ◽  
Vertical Test

Leaching outdoor tests (LOT) are commonly used to assess the leaching of substances from construction materials. In this context, the amount of stormwater in contact with the surface material is of special interest for analyzing the runoff loads of substances from building façades. A numerical model was developed in MATLAB on the basis of previous analytical models to calculate the collected stormwater runoff volumes from the vertical test panels (VTP) during LOT. In the model, wind-driven rain (WDR) is considered to be the main mechanism for determining the amount of water impinging on the VTP, so it is a crucial factor in the modeling for the façade runoff. The new model makes it possible to simulate the runoff volumes from VTP that are covered with a wide variety of plaster and mortar. Using the new model, it was possible to relate the VTP runoff volumes obtained during an 18-month sampling period for LOTs performed at the Fraunhofer Institute for Building Physics in Valley, Germany. When comparing the simulation results with the field test accumulated runoffs, the model exhibited a difference of no more than 3.5% for each of the analyzed materials. The simulation results are satisfying, and the paper demonstrates the feasibility of the modelling approach for the runoff assessment of VTP covered with a variety of plaster and mortar.

Coupled Pitch Links for Multiharmonic Isolation Using Fluidic Circuits

2014 ◽  
Vol 59 (4) ◽  
pp. 1-11
Author(s):  
Lloyd H. Scarborough III ◽  
Christopher D. Rahn ◽  
Edward C. Smith ◽  
Kevin L. Koudela
Keyword(s):  
Experimental Validation ◽  
Analytical Models ◽  
Main Rotor ◽  
Fluidic Devices ◽  
Simulation Results ◽  
Fluidic Circuits ◽  
Blade Loads

Replacing stiff pitch links on rotorcraft with coupled fluidic devices has the potential to reduce the aerodynamic blade loads transmitted through the pitch links to the swashplate. Analytical models of two fluidic devices coupled with three different fluidic circuits are derived. These passive fluidlastic systems are tuned, by varying the fluid inertances and capacitances of each fluidic circuit, to reduce the transmitted pitch-link loads. The different circuit designs result in transmitted pitch-link loads reduction at up to three main rotor harmonics. The simulation results show loads reduction at the targeted out-of-phase and in-phase harmonics of up to 88% and 93%, respectively. Experimental validation of two of the fluidic circuits demonstrates loads reduction of up to 89% at the out-of-phase isolation frequencies and up to 81% at the in-phase isolation frequencies.

scholarly journals Kinematic Analysis of Three-Wire-Driven Parallel (TWDP) Robot

2011 ◽  
Vol 2-3 ◽  
pp. 302-307 ◽  
Author(s):  
Tao Yu ◽  
Qing Kai Han
Keyword(s):  
Static Analysis ◽  
Parallel Robot ◽  
Analytical Models ◽  
Kinematics Analysis ◽  
Mechanism Model ◽  
Good Movement ◽  
Dynamics And Control ◽  
Movement Stability ◽  
Simulation Results ◽  
And Control

In the paper, a novel new gravity-constrained (GC) three-wire-driven (TWD) parallel robot is proposed. With its mechanism model, three typical kinematics analytical models, including horizontal up-down motion, pitching motion and heeling motion and their corresponding simulations are given in detail. In static analysis, the change of tensions in the wires is calculated based on previous kinematics analysis. The simulation results show the robot has good movement stability. The paper can provide useful materials to study of dynamics and control on wire-driven robot.

Study of Rider Model for Motorcycle Racing Simulation

2020 ◽  
Author(s):  
Masatsugu Nishimura ◽  
Yoshitaka Tezuka ◽  
Enrico Picotti ◽  
Mattia Bruschetta ◽  
Francesco Ambrogi ◽  
...  
Keyword(s):  
Predictive Control ◽  
Running Speed ◽  
Steering Angle ◽  
Conventional Model ◽  
Linear Region ◽  
New Model ◽  
Constant Radius ◽  
Simulation Results ◽  
Braking Force ◽  
Motorcycle Dynamics

Various rider models have been proposed that provide control inputs for the simulation of motorcycle dynamics. However, those models are mostly used to simulate production motorcycles, so they assume that all motions are in the linear region such as those in a constant radius turn. As such, their performance is insufficient for simulating racing motorcycles that experience quick acceleration and braking. Therefore, this study proposes a new rider model for racing simulation that incorporates Nonlinear Model Predictive Control. In developing this model, it was built on the premise that it can cope with running conditions that lose contact with the front wheels or rear wheels so-called "endo" and "wheelie", which often occur during running with large acceleration or deceleration assuming a race. For the control inputs to the vehicle, we incorporated the lateral shift of the rider's center of gravity in addition to the normally used inputs such as the steering angle, throttle position, and braking force. We compared the performance of the new model with that of the conventional model under constant radius cornering and straight braking, as well as complex braking and acceleration in a single (hairpin) corner that represented a racing run. The results showed that the new rider model outperformed the conventional model, especially in the wider range of running speed usable for a simulation. In addition, we compared the simulation results for complex braking and acceleration in a single hairpin corner produced by the new model with data from an actual race and verified that the new model was able to accurately simulate the run of actual MotoGP riders.

scholarly journals Active-Varying Sampling-Based Fault Detection Filter Design for Networked Control Systems

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Yu-Long Wang ◽  
Tian-Bao Wang ◽  
Wei-Wei Che
Keyword(s):  
Fault Detection ◽  
Control Systems ◽  
Networked Control Systems ◽  
Filter Design ◽  
Sampling Period ◽  
Networked Control ◽  
Packet Dropouts ◽  
Fault Detection Filter ◽  
Simulation Results ◽  
Detection Filter

This paper is concerned with fault detection filter design for continuous-time networked control systems considering packet dropouts and network-induced delays. The active-varying sampling period method is introduced to establish a new discretized model for the considered networked control systems. The mutually exclusive distribution characteristic of packet dropouts and network-induced delays is made full use of to derive less conservative fault detection filter design criteria. Compared with the fault detection filter design adopting a constant sampling period, the proposed active-varying sampling-based fault detection filter design can improve the sensitivity of the residual signal to faults and shorten the needed time for fault detection. The simulation results illustrate the merits and effectiveness of the proposed fault detection filter design.

A New Lattice Boltzmann Model for Phase Transition Process

2009 ◽  
Author(s):  
Longjian Li ◽  
Jianbang Zeng ◽  
Quan Liao ◽  
Wenzhi Cui
Keyword(s):  
Phase Transition ◽  
Lattice Boltzmann ◽  
Equations Of State ◽  
Density Ratio ◽  
Transition Process ◽  
Lattice Boltzmann Model ◽  
New Model ◽  
Phase Transition Process ◽  
Simulation Results ◽  
Boltzmann Model

A new lattice Boltzmann model, which is based on Shan-Chen (SC) model, is proposed to describe liquid-vapor phase transitions. The new model is validated through simulation of the one-component phase transition process. Compared with the simulation results of van der Waals fluid and the Maxwell equal-area construction, the results of new model are closer to the analytical solutions than those of SC model and Zhang model. Since the range of temperature and the maximum density ratio are increased, and the value of maximum spurious current is between those of SC and Zhang models, it is believed that this new model has better stability than SC and Zhang models. Therefore, the application scope of this new model is expanded. According to the principle of corresponding states in Engineering Thermodynamics, the simulations of water and ammonia phase transition process are implemented by using this new model with different equations of state. Compared to the experimental data of water and ammonia, the results show that the Peng-Robinson equation of state is more suitable to describe the water, ammonia and other substances phase transition process. Therefore, these simulation results have great significance for the real engineering applications.

The New Rural Residential Building Materials of Low Carbon Mode of Thinking

2012 ◽  
Vol 443-444 ◽  
pp. 110-114
Author(s):  
Yuan Luo
Keyword(s):  
Real Estate ◽  
Rural Areas ◽  
Building Materials ◽  
Construction Materials ◽  
Residential Building ◽  
Actual Situation ◽  
Low Carbon ◽  
New Model ◽  
Construction Methods ◽  
Current Transition

In the current transition conditions, living in rural areas how to form a new model to address the issue of live and living is very necessary. Mountainous rural areas and more for less, construction methods and how to inject carbon idea behind such issues as the actual situation in rural areas of the construction line tools and real estate construction materials, forming a certain significance of the ideas and methods.

Upgrading the Building Facades in Low-Density Residential Areas

2020 ◽  
pp. 216-243
Author(s):  
Katerina Tsikaloudaki ◽  
Dimitra Tsirigoti ◽  
Stella Tsoka ◽  
Theodore Theodosiou
Keyword(s):  
Energy Performance ◽  
Building Envelope ◽  
Building Performance ◽  
Residential Areas ◽  
Energy Needs ◽  
Building Facades ◽  
Thermal Bridging ◽  
Negative Impacts ◽  
Building Physics ◽  
Common Action

The most common action for the buildings' energy upgrade across Europe is the addition of thermal insulation on the external walls. Such interventions, although simple on their construction, cause significant changes on the building's behavior, not only on its energy needs, but also on the hygrothermal and visual performance. The effects are not always positive; for example, thicker insulation may result in lower thermal transmittance and better thermal energy performance, but on the other hand the thermal bridging effect is amplified, and the daylight levels are decreased. This research intends to quantify these impacts by analyzing the relevant parameters for different regions of Europe. The analysis aims at explaining the complicated interrelationships on the building physics' aspects encountered through interventions on the building envelope, but also at identifying appropriate measures that could counterbalance the negative impacts and enhance the overall building performance.

Coupled Pitch Links for Multi-Harmonic Isolation Using Fluidic Circuits

2012 ◽  
Author(s):  
Lloyd H. Scarborough ◽  
Christopher D. Rahn ◽  
Edward C. Smith ◽  
Kevin L. Koudela
Keyword(s):  
Analytical Models ◽  
Main Rotor ◽  
Fluidic Devices ◽  
Simulation Results ◽  
Fluidic Circuits ◽  
Blade Loads ◽  
Even Harmonics

Replacing rigid pitch links on rotorcraft with coupled fluidic devices has the potential to reduce the aerodynamic blade loads transmitted through the pitch links. Analytical models of two fluidic devices coupled with three different fluidic circuits are derived. These passive fluidlastic systems are tuned, by varying the fluid inertances and capacitances of each fluidic circuit, to reduce the transmitted pitch-link loads for up to three main-rotor harmonics. The simulation results show loads reduction at the targeted odd and even harmonics of at least 95% and 72%, respectively.

scholarly journals Potential for Use of Veneer-Based Multi-Material Systems in Vehicle Structures

2019 ◽  
Vol 809 ◽  
pp. 633-638
Author(s):  
David B. Käse ◽  
Giovanni Piazza ◽  
Elmar Beeh ◽  
Horst E. Friedrich ◽  
Daniel Kohl ◽  
...  
Keyword(s):  
Thin Sheet ◽  
Construction Materials ◽  
Natural Material ◽  
Lightweight Construction ◽  
Sustainable Solutions ◽  
Second Moments ◽  
Fraunhofer Institute ◽  
Material Systems ◽  
German Aerospace ◽  
The University

In the past, the focus for the development of modern vehicle structures was very much on lightweight construction. However, there are increasing aspirations to develop not only light but also sustainable solutions which use resources efficiently. As a result, natural materials become more attractive compared to conventional lightweight construction materials. The "For (s) tschritt" research project investigates the use of veneer-based multi-material systems in vehicle structures. For this purpose, various concepts were developed, ranging from a use of the material to reinforce thin sheet metals to structural components which are produced completely from wood and are only reinforced locally. In order to evaluate the aspired solutions, generic components were derived, manufactured at the Department for Cutting and Joining Manufacturing Processes of the University of Kassel (TFF) and the Fraunhofer Institute for Wood Research, Wilhelm-Klauditz-Institut (WKI), and tested at the Institute of Vehicle Concepts of the German Aerospace Center (DLR). The advantages of the use of wood are particularly evident in structures which are subjected to bending stress and pressure loads: As a result of the lower density, they can be designed with reinforcement. This allows the second moments of inertia to be increased without affecting the weight. The disadvantages of the natural material, such as reduced reproducibility and the complex failure behaviour, are offset by systematic hybridisation of wood and the use of veneer multilayer composites.

Prediction of Collapse Area of Construction Materials for Cooling Tower with Different Cut Height Due to the Blasting Demolition

2016 ◽  
Vol 723 ◽  
pp. 801-806
Author(s):  
Tie Jun Tao ◽  
Lian Sheng Liu ◽  
En An Chi ◽  
Ming Sheng Zhao
Keyword(s):  
Numerical Simulation ◽  
Finite Element ◽  
Cooling Tower ◽  
Construction Materials ◽  
Ground Vibration ◽  
Parallel Study ◽  
Finite Element Software ◽  
Dynamic Finite Element ◽  
Simulation Results

The effect of cut height on collapse area is simulated and analyzed by dynamic finite element software. Meanwhile, the simulated collapse processes of the cooling tower with different cut height were completed in a parallel study, the results of which are briefly introduced in this paper. The results show that: as the cut height increases, ground vibration on surrounding structures and collapse area of cooling tower decreases. At last, numerical simulation results were used in blasting project, which reduced hazard of collapse vibration and verify the scientific of this method.

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