Active Road Rumble Energy Harvesting Panels

Vehicles traveling through busy roads and highways waste a huge portion of their kinetic energy. Up to five percent of the car’s energy is lost due to braking. In an effort to save energy it is possible to harvest some of this lost energy through a mechanical device built into the road. With over 1 billion cars, there is a huge potential for a man made untapped energy to be collected and harvested. This presentation focuses on designing a mechanical system that collects the energy of cars passing over a depressible flapping road rumble panel. As the car passes over the flap, the panel depresses and turns a directional shaft. The energy of many panels is collected and is summed up in a continuously turning flywheel. The collected mechanical energy can then be converted into electrical energy. The panels would be located where car drivers encounter deceleration ramps, when approaching a stop sign or entering a toll plaza. The analysis of this active road rumbles concept involved 1) designing a prototype using a computer drawing software such as SolidWorks, then 2) modeling the system mathematically to figure out all the important and intervening parameters factoring in the expression of the equation of motion of such systems, and then finally 3) building a physical prototype to analyzes the performances of such systems. The SolidWorks drawings for the model have been created. The dynamical model used free body diagrams and Newton’s second laws to determine the different loads and the equation of motion of the road rumble system. The mathematical model took into consideration the parameters of a shock absorber with a spring/mass/damper system. The kinematic equations of the shaft and flywheels were used to determine the speed and acceleration of the power train. A physical prototype was tested manually for time and frequency responses. It has been found that the energy collecting flywheel is lightly damped and loses a small part of its energy to friction. A feasibility study was conducted to evaluate the economic viability of such system. The harvested energy was estimated by measuring the RPM of the flywheel, and it was found that such system have an acceptable return on the investment. It is envisioned that such harvesting energy systems can be used in many ways one of them is to empty a huge offshore silo tank filled with sea water and producing peak electrical energy by allowing the sea water back into the silo through a hydraulic turbine.

Enhanced Electrical and Mechanical Properties of Nanotube Reinforced Composites

Halloysite nanotube (HNT) and clay were introduced into the composites to improve the dispersion of MWNT. Combining the nanotubes with HNT/clay allows both electrical and mechanical behavior to be simultaneously enhanced with the addition of HNT and clay, dielectric property is also increased tremendously. MWNTs appear to have an affinity for clay that causes them to become more exfoliated and better networked in these composites.

Computational Study of Single-Sided Ventilation Through a 3-Dimensional Room With Rounded Edges

A commercial Computational Fluid Dynamics (CFD) software package is used to investigate numerically a 3-dimensional rectangular-box room with rounded edges. The room has all its window openings located on one wall only. The standard K-ε turbulence model is used. Air’s flow rate and flow pattern are considered in terms of wind speed and the openings’ characteristics, such as their number, location, size and shape. Especially, comparison with ventilation rate corresponding to when the room edges are sharp is made; and thereby the effects of the edges being rounded are examined.

Modeling and Simulation Method Comparison for the Lotka-Volterra Model

The Lotka-Volterra or predator-prey models contain a pair of first order, non-linear, differential equations, which describe the dynamics of two species interaction in biological systems. Hence, accurate simulation strategies development for mentioned equations is crucial. In this paper, first, the presented model equations are simulated by ARX, ARMAX and BJ parametric models of the Identification Toolbox in MATLAB software. Afterwards, this simulation has been done in the Neural Network Toolbox by Feed-Forward and Elman networks with equal number of neurons, layers and same transfer functions. Finally, the results of these two simulations have been compared to introduce the best simulation methodology. It is shown that more accurate results are achieved by Elman network. In addition, the paper demonstrates that the simulation error can be decreased by simply increasing the number of these neural networks’ neurons.

Performance Analysis of a Simplified Model of Cooling Load for a Typical Office Building

Buildings are responsible for at least 40% of energy use in most countries of the world, and for up to 21% of greenhouse gas emissions globally. As this trend continues, real-time building load measurements are essential for dynamic load response control, understanding and improvement of load distributions and profiles, and for climate-responsive design, particularly in commercial buildings. The focus in this paper is the cooling load, which is the rate at which heat must be removed from the controlled zone to maintain the desired temperature. Estimation of maximum cooling load is necessary for sizing of cooling equipments. However, details needed for whole-building simulation are often unreliable or unavailable. As such, simplified models with reasonable accuracy and computational requirements are often used. A cyber-physical system, integration of physical sensors and mathematical model, is proposed in this paper for cooling load estimation. The physical sensor measurements are limited to outside air temperature, solar radiation, room air temperature, and building plug load. Meanwhile, resistance-capacitance (RC) concept was adopted to describe the physics and dynamics of the building envelope for its simplicity and reasonable computational requirements. The cyber-physical system was tested using a typical office having two thermal zones and compared with simulation results from EnergyPlus, a whole building simulation program. Phenomenon such as infiltration, inter-zone air mixing, and air moisture control were not taken into account for the model. Results are presented to determine the accuracy of the simplified model for cooling load estimation.

Effect of Catalyst Used in the Sol-Gel Process on the Microstructure and Adsorption/Desorption Performance of Silica Aerogels

Silica aerogels are often deployed as solid desiccants in enthalpy wheels used for dehumidifying ventilation air in air-conditioning systems. These materials have good adsorption and desorption characteristics, but microstructure affects their moisture diffusivity. As the performance of desiccant systems depends on diffusivity, it is important to select a preparation method providing the desired aerogel microstructure for enhanced dehumidification performance. A study is described in which the structure of silica aerogels prepared by the Sol-Gel process is analyzed. The same precipitator (TMOS-Tetra methyl orthosilicate) and solvent (Methanol) are used to prepare all samples. It is found that density and microstructure are highly dependent on the catalyst used in the Sol-Gel process. Dynamic vapor sorption experiments are conducted to determine diffusivity. Microscopic images are analyzed to discern the structure and to relate it to corresponding adsorption or desorption performance parameters.

Rotary Multimodal Energy Harvesting Device

In this paper, a new multimodal energy harvesting device consisting of two transduction mechanisms and having unique properties at various operating modes is presented. The hybrid system includes electromagnetic and piezoelectric energy harvesting technologies, and uses linear motion and impact forces from human motion for energy harvesting. The device is based on an unbalanced electromagnetic rotor made of three beams of piezoelectric material that have magnets attached to the ends. The device is to be worn on the legs or arms of a person. Linear motion, from the arms or legs swinging, causes the rotor to spin and the magnets to pass over the coils. Impact forces, from stepping, induce stress on the piezoelectrics which generates voltage across the electrode. The results of several numerical simulations are presented. For the piezoelectric beams, numerical simulations were done to find the deflection, stress, optimum operating frequency, and mode shapes taking into account environmental conditions. For the electromagnetic generation, numerical simulations were done to find the optimal load resistance and power generation for several different orientations. Other design related issues will also be investigated to fully realize the device in real world applications.

An International Outlook of Innovative Energy Efficient Designs of Low Carbon Buildings

The Developing communities in their path for rapid development is endeavoring to make all necessary and appropriate measures to enhance the efficiency of energy utilization and increase the beneficiation of the energy resources. The energy production, transmission, distribution and utilization efficiency becomes a vital factor and measure of national development. Governmental organizations were established earlier to be responsible for energy planning and efficient utilization, information dissemination and capacity building as well as devising the necessary codes and standards. Throughout the Nation Energy resources are widely used and consumption rates are in general exceeding the International accepted values. Energy rationalization and audit exercises were developed and monitored by Governmental authorities, Universities and Research centers through the past two decades with a definitive positive energy reduction and beneficiation. The development of the relevant codes for Residential and Commercial Energy Efficiency in Building is underway through the governmental bodies responsible for the research and development in the building Technology sector and is the umbrella under which the National and Unified Arab Codes are developed and issued. A proposed new Energy Performance in Buildings Directive based on relevant ISO, ASHRAE and LEED would be beneficial to practitioners to meet the following targets of Energy Performance Directive: 1. “Legestilative authorities shall ensure that, when buildings are constructed, sold or rented out, an energy performance certificate should be made available to the owner. 2. The energy performance certificate for buildings shall include reference values such as currant legal standards and benchmarks in order to make it possible for consumers to compare and assess the energy performance of the building. The certificate shall be accompanied by recommendations for cost-effective improvement of the energy performance…”.Ultimately a unique energy standard is sought for Middle East region to harness the energy consumption. This can be achieved by developing methodologies for energy declaration of the buildings and to provide a labeling system and energy signature for selected buildings.

Effect of Build Orientation on Mechanical Properties of Rapid Prototyping (Fused Deposition Modelling) Made Acrylonitrile Butadiene Styrene (ABS) Parts

Prototyping is the process of building pre-production models of a product to test various aspects of its design. Fused deposition modeling (FDM) is a process for developing rapid prototype (RP) objects by depositing fused layers of material according to numerically defined cross sectional geometry. The quality of FDM produced parts is significantly affected by various parameters used in the process. This paper aims to study the effect of one such parameter i.e., build orientation, on mechanical properties (mainly tensile and compressive strength) of FDM processed parts. In rapid prototyping (FDM), the orientation of the parts during fabrication is critical as it can affect part strength such as tensile and compressive strength. Specimens are prepared for tensile/compression test as per ASTM standards. It was found that the build orientation of the specimen has more of an impact on strength. The layering build process of rapid prototyping creates a variance in strength depending on the build orientation. The D695 standard allows for stable compression testing and is used for compression testing. Several geometries are allowed for tension specimens under the D638 standard. We chose the type I specimen as it is the most commonly used and best fit our mechanical testing equipment. From the tensile test result, it is found that when build orientation is increasing from 0° to 90°, ultimate tensile strength decreases. It is maximum at 0° orientation i.e., 15.2 MPa and minimum at 90° orientation i.e., 11.6 MPa. The tensile stress at 0° (i.e. axial direction) is 23.68 % higher than transverse direction (i.e., 90°). From the compressive test results, it is found that, when sample orientation is increasing from 0° to 90°, the ultimate compressive strength decreases. It is maximum at 0° orientation i.e., 26.66 MPa and minimum at 90° orientation i.e., 22.22 MPa. The compressive stress at 0° (i.e. axial direction) is 16.65 % higher than transverse direction (i.e. 90°).

Using the Bootstrap Method to Determine Uncertainty Bounds for Change Point Utility Bill Energy Models

Statistical inverse modeling of energy use in buildings and of HVAC&R equipment and systems has been widely researched, and are fairly well ingrained in the profession. However, there are still a few nagging issues; one of them is related to the accuracy in estimating model prediction uncertainty bands at a pre-specified confidence level. This issue is important since it bears directly on the risk associated with the identified energy savings. While several papers have been published dealing with uncertainty in statistical models, the non-heteroscedascity and the non-gaussian behavior of the residuals are problematic to handle using classical statistical equations of model prediction uncertainty. This paper proposes and illustrates the use of the Bootstrap method as a robust and flexible alternative approach to determining uncertainty bands for change point model predictions identified from utility bills. In essence, the bootstrap method works by taking a data set and resampling it with replacement. In the case of utility bill analysis, one starts with 12 data points representing energy use for each month of the year. Such samples are repeatedly generated to produce a large (say, m) number of synthetic data sets from which m different change point models can be identified. These m models are used to make predictions at any pre-specified outdoor temperature, and the 95% (or any other) prediction interval bands can be determined non-parametrically from the m data predictions. This paper fully describes and illustrates this approach along with a case study example.