Effect Weibull Distribution Parameters Calculating Methods on Energy Output of a Wind Turbine: A Study Case
IJTEE, volume-14 , Issue 2 (2018), PP 163 - 173
Published: 15 Jan 2018
by Abeer Qawasmi, Suhil Kiwan from Mechanical Engineering Department, Jordan University of Science and Technology, Irbid 22110, Jordan
Abstract: Wind energy is an important renewable energy source. It is considered as one of the most significant, freely available and alternative source of energy distributed throughout the world. The estimation of the potential of wind energy in a site plays a vital role in estimating the energy output of the wind turbines and, therefore, affects economics and decision making. Site characterization can be expressed mathematically in different methods. Weibull distribution is one of the most common methods used to represent wind energy potential in a site. In this study, wind speed data was collected for year 2013, from Jan 2013 to Dec 2013. The data collected for three different heights (20 m, 40 m and 60 m) from measurement station installed at Jordan University of science and technology campus area (Irbid, Jordan). The data recorded based on ten minutes averages using a data logger. Yearly shape factor (k) and scale factor (c), of Weibull distribution for the wind speed are calculated for each height using graphical and standard deviation methods. Both arithmetic and cubic mean wind speeds were used to estimate Weibull parameters. Then, the energy outputs of Vestas V80-2.0 wind turbine installed at the site were estimated using calculated Weibull parameters and actual estimation. The results are compared to check the accuracy of methods of estimating Weibull parameters. A new method of characterizing the site is proposed and tested. The method is based on Weibull distribution but the specific power density is the main variable of the distribution function. The results showed that this method is the most accurate method among all tested methods. read more... read less...
Keywords: Wind power, Weibull distribution, Irbid-Jordan
Analyzing Sustainable Development Impacts of Large-Scale Clean Development Mechanism Projects on Host Countries
IJTEE, volume-14 , Issue 2 (2018), PP 153 - 161
Published: 10 Jan 2018
by Sultan Al Awadhi, Zeina Abbas, Toufic Mezher from Institute Center for Smart and Sustainable Systems (iSmart) Masdar Institute of Science and Technology, Abu Dhabi, UAE
Abstract: The objective of the Clean Development Mechanism (CDM) is to assist developed countries in achieving their emission reduction target levels and to contribute to the sustainable development of host countries. A Gold Standard (GS) rating system was developed to assess the value of emission certificates of existing CDM projects. In this paper, a framework was developed to analyze the true impact of CDM projects on host countries economically, socially, and environmentally. In addition, a comparative analysis is conducted between GS certified and non-certified projects to see which projects can be categorized as GS through Applied Statistical Inference techniques. Results show that the major impact of CDM projects was mainly related to job creation and reducing CO¬¬¬2 emissions. In addition, statistical analyses show that the sustainability filter in GS has many flaws and should be re-evaluated in order to be used as a rating system for CDM projects. read more... read less...
Keywords: Clean Development Mechanism, Gold Standard, sustainability, sustainable development.
IJTEE, volume-14 , Issue 2 (2018), PP 143 - 151
Published: 08 Jan 2018
by M. A. Hamdan, K. K. Kardasi from The University of Jordan, Amman, Jordan
Abstract: The performance of PV (photovoltaic) module is strongly dependent on its operating temperature. Most of the energy absorbed by the panel is converted to heat which is normally lost and provides no value. This work investigated experimentally the PV performance through using three separated PV panels. Three identical photovoltaic (PV) panels have been installed side by side to investigate the effect of cooling on the PV panels performance, one of them is used as a baseline ; the second is cooled using pure water; while the third is cooled using nanofluids. Aluminum Oxide (Al2O3) and Copper Oxide (CuO ) nanoparticles were added to the pure water to form the nanofluid, each one with different concentration in order to find the optimum concentration of Al2O3 and CuO. Meteorological data was measured using a weather station. Also, the temperature of the cooling fluids together with the backside temperature of the PV Panels was recorded. It was found that an increase in the efficiency of the panel of 2% was obtained when 0.4 % Al2O3 by weight was mixed with the pure water. This increase in efficiency was 2.34% when 0.6 % CuO. read more... read less...
Keywords: PV Cooling, Nanofluid, Solar Energy
A Comparative of Energy Efficiency of Luminaries for General Lighting for a Residential Building: CFL vs LED
IJTEE, volume-14 , Issue 2 (2018), PP 125 - 129
Published: 08 Jan 2018
by Maysa Sarsour, Ahmed Al-Salaymeh from Electrical Engineer, Arabtech Jardaneh Group, Amman, Jordan Mechanical Engineering Department, School of Engineering, University of Jordan, Amman 11942, Jordan
Abstract: This paper presents comparison study between two types of lighting technologies; the compact fluorescent lighting (CFL) and light emitting diode (LED) luminaries for home general lighting usage. This study includes all parts of the luminaries that include the lamp itself and the housing. An experimental test was done to verify the luminance produced by the two technologies. The generated energy of the two technologies was compared by using DIALUX software under the same lumen flux. Furthermore, the associated cost is also evaluated over the stipulated operational period which shows the most advantages of the LED technology over CFL although the initial capital cost for LED is 22% higher than CFL. However, this increment can be equalized by a short payback period of nearly 18 months for the case. This comparison shows that the LED luminaries have the advantages of a significant reduction in the environmental impact, i.e. reduction of 41-50% of greenhouse gas emission and energy demand, mainly due to lower energy utilization and substantial reduction of 60-78% in electrical consumption. read more... read less...
Keywords: LED; CFL; DIALUX; Energy Efficiency
IJTEE, volume-14 , Issue 2 (2018), PP 119 - 124
Published: 07 Jan 2018
by Mohammad Alsmadi, Yousef Dababneh, Ahmed Al-Salaymeh from Performance and Efficiency Department, KEPCO KPS Plant Services and engineering Co. Ltd, Amman, Jordan Renewable Energy Department, Wathba Investment Co., Amman, Jordan Mechanical Engineering Department, The University of Jordan, Amman, Jordan
Abstract: The purpose of this study is to investigate the utilization of PV feeding system for auxiliary energy demand in the conventional power plants. A 573 MW tri-fuel power plant in Jordan IPP3 the largest internal combustion engine (ICE) power plant in the world is the case study to evaluate the energy economy aspects of PV feeding system and its effects on the monthly payments for this energy. All relevant computations will be performed in order to end up with reasonable, feasible and applicable results. The auxiliary energy demand of this power plant while no operation is covered from the national transmission grid which results in around 48 MWh imported energy on daily basis taking in mind no operation case. Therefore, such PV system will have a noticeable impact over the productivity of the whole plant as well as raising the money spent for fuel upon the reduction of the heat rate. The PV system is sized to have a capacity of 2 MWp planned to be utilized during the day time. Considering the imported energy benefit, the corresponding pay-back period will through the 5th year where is expected to be accomplished during the 7th year when it comes to the heat rate improvement. The prominent fact to be mentioned here that the pay-back period upon either imported energy benefit of heat rate improvement is calculated separately. read more... read less...
Keywords: Energy, Auxiliary, Imported.
IJTEE, volume-14 , Issue 2 (2018), PP 109 - 118
Published: 07 Jan 2018
by B.R. Qawasmeh, A. Al-Salaymeh, Ma’en S. Sari, Nadeen Elian, Nadeen Zahran from Mechanical Engineering Department, The University of Jordan, Amman 11942, Jordan Mechanical and Maintenance Engineering Department, German Jordanian University, Amman 11180, Jordan
Abstract: The energy rating for residential buildings in Amman is studied and a rating scale is suggested. The annual cooling and heating energy requirement has been calculated according to Jordanian codes, using Hourly Analysis Program (HAP) and degree-days method (DD). The energy rating which provides the necessary information about the energy performance of the residential buildings has been assessed. The assessment is based on the thermal envelope. The annual energy loads are calculated for different cases according to different parameters such as glass layers for windows, and direction of the apartment. Two main cases are considered in constructing the energy rating scale; the cases are two apartments (one directed to the right while the other is directed to the left) located in Marka, Amman, Jordan. The two apartments have the same area of 110 m2 and in the same building's floor. The different orientations have been considered for the apartments of 90, 180 and 270 degree clock wise rotations. Then, the heating and cooling loads are calculated for all orientations using single glass and double glass. The annual cooling and heating energy without rotation using degree-days method (DD): for case one are 123.8 kWh/m² (for single glass) and 112.8 kWh/m² (for double glass), and for case 2 are 125.9 kWh/m² (for single glass) and 114.6 kWh/m² (for double glass) at Tb=18.3 Ԩ for heating and Tb =24 Ԩ for cooling. These results are in good agreement with the HAP results. Finally, an energy rating scale was suggested for residential buildings in Amman. read more... read less...
Keywords: Energy Rating, Degree-Days Method, Simulation
IJTEE, volume-14 , Issue 2 (2018), PP 103 - 108
Published: 07 Jan 2018
by M. A. Hamdan, E. Abdelhafez, and O. Ghnaimat from University of Jordan, Amman, Jordan Al-Zaytoonah University of Jordan, Amman, Jordan The Royal Scientific Society, Amman, Jordan
Abstract: In this study, three Artificial Neural Network (ANN) models (Feedforward network, Elman, and Nonlinear Autoregressive Exogenous (NARX)) were used to predict hourly solar radiation in Amman, Jordan. The three models were constructed and tested by using MATLAB software. Meteorological data for the years from 2000 to 2010 were used to train the ANN while the yearly data of 2011 was used to test it. It was found that ANN technique may be used to estimate the hourly solar radiation with an excellent accuracy, and the coefficient of determination of Elman, feedforward and NARX models were found to be 0.97353, 0.97376, and 0.99017, respectively. The obtained results showed that NARX model has the best ability to predict the required solar data, while Elman and feedforward models have the lowest ability to predict it. read more... read less...
Keywords: Solar Radiation, Artificial Neural Networks, Prediction
IJTEE, volume-14 , Issue 2 (2018), PP 95 - 101
Published: 07 Jan 2018
by Essam E. Khalil and Sherif M. Gomaa from Mechanical Engineering Department, Cairo University, Giza, Cairo11321, Egypt
Abstract: Fire propagation and control in underground car parks are of an important safety issue. This paper investigates the effect of the jet fan system on the smoke clearance in an underground car park using CFD simulations. Two fire locations were considered under a steady state fire source of 4 MW. The consideration of the fire zone was also studied. The underground car park used in this study is 5,290 m2 in area with a height of 3.7 m. A comparison between CFD results and analytical correlations for the fire modeling was made. The ANSYS FLUENT 14.0 software was used for all simulations. The results showed that the temperature is limited to the zone, where the fire is detected, and it is within an accepted range. The CO2 mass fraction was presented and showed how the jet fans contribute in reducing the smoke density and hence improve the visibility. It was found that dividing the car park into zones is highly recommended and should be taken in the design of the jet fan system. read more... read less...
Keywords: CFD, Fire Simulation, Dynamic Simulation, Car Parks
IJTEE, volume-14 , Issue 2 (2018), PP 89 - 93
Published: 07 Jan 2018
by S.M. Henkanatte-Gedera, T. Selvaratnam, N. Nirmalakhandan from Civil Engineering Department, New Mexico State University, Las Cruces, NM 88003, USA
Abstract: Meeting the demand for food, energy, and water to sustain the worldwide growth of urban population is a major challenge. Several recent reports have concluded that one approach to overcome this challenge is to recover and recycle resources within the food-energywater (FEW) nexus in urban settings. Urban wastewaters (UWW) are now being recognized as a resource, rich in nutrients and energy, rather than a waste stream that has to be treated and disposed of at the expense of significant energy input and associated environmental emissions. Reclaiming reusable water, nutrients, and energy from UWWs can contribute to autarky of FEW nexus and render the wastewater management process sustainable and potentially profitable. This paper presents a novel approach to treat UWW with the potential for high recovery of energy, nutrients, and water from UWW for use in food crop production. This approach entails cultivation of energy-rich algal biomass in primary-settled UWW followed by extraction of biocrude and nutrients from the algal biomass by hydrothermal liquefaction. A fraction of the recovered nutrients is recycled to boost biomass production while the rest can be stockpiled for use as fertilizer. Results from a pilot scale field study conducted at a local wastewater treatment plant confirmed that the algal system can achieve >80% removal of organic carbon, ammoniacal-nitrogen, and phosphates in UWW, meeting the respective discharge standards in a single step, with a batch process time of three days. read more... read less...
Keywords: Wastewater, energy recovery, nutrient recovery, algal cultivation
Techno-Economic Study of PV Powered Brackish Water Reverse Osmosis Desalination Plant in the Jordan Valley
IJTEE, volume-14 , Issue 1 (2018), PP 83 - 88
Published: 07 Jan 2018
by Ahmad Alsarayreh, Mohammad Majdalawi, Ramchandra Bhandari from Independent researcher in Renewable Energy, Amman, Jordan University of Jordan, Amman, Jordan TH Köln – University of Applied Sciences, Cologne, Germany
Abstract: Jordan is one of the ten most water scarce countries in the world. In 2014, the share of water per capita per year in Jordan is 120 Cubic Meters (m3 ). The water deficit is estimated to be 160 Million Cubic Meter (MCM) in 2015. This deficit is projected to grow up to 490 MCM by 2025. This study discusses the possibility of using solar energy for brackish water desalination in Jordan Valley (JV) to reduce the pressure on the fresh water and the conventional energy consumption associated with the desalination process, as well as, to reduce Greenhouse Gases (GHG) emissions associated with the consumption of energy produced from fossil fuels. Photovoltaic (PV) powered brackish water reverse osmosis desalination technology (RO) has been investigated in this study. The PV system has designed using PVSOL software. The economic feasibility study of use PV system has been done using Average Incremental Cost of Water (AICOW), Internal Rate of Return (IRR) and Net Present Value (NPV) in several scenarios. The results of the analysis showed that using PV systems for brackish water desalination for a small size single plant at current electricity tariff is not economically feasible for the farmers. But it is feasible for a larger size plant for ten farms or more, or with financial support from the government. The feasibility results showed that using PV systems for brackish water desalination for the government side are economically feasible even for a small size plant. read more... read less...
Keywords: Desalination, Brackishwater, Solar Energy, Photovoltaic.
IJTEE, volume-14 , Issue 1 (2018), PP 71 - 82
Published: 07 Jan 2018
by A. Al Anzi and L. Al-Dihani and A. Al-Ragam from College of Architecture, Kuwait University, Kuwait Kuwait Municipality, Kuwait City, Kuwait
Abstract: The paper focuses on diagnosing the Double Skin Facade (DSF) of the main Kuwait Municipality building complex based on occupants’ perception of different historical and environmental preferences. The case study building complex has a remarkable façade that represents the modern architectural and democratic movement of Kuwait. Unfortunately, due to improper maintenance and operation, the significance and benefits of the DSF in particular have not been utilized in this complex. The objective of this paper is to diagnose the DSF benefits of this building envelope and discuss the feasibility of renovation to improve its sustainable use and operation. Such sustainability includes daylighting, thermal comfort, indoor air quality (IAQ), and acoustic performances. To reach this objective, the study will be carried out using quantitative and qualitative research methods, such as site visits, interviews, questionnaire and literature review. It is found that responses of occupants are positive on the advantages and rehabilitations of the DSF of the complex. And based on the findings of this study, it is also believed by the authors that the preservation of its DSF is a more sustainable choice in this green architectural era. This is so due to its great occupants’ performance expectations and energy savings opportunities. read more... read less...
Keywords: Double Skin Facade, Facade Rehabilitation, Multiple-Skin Façade, Sustainable façade, thermal comfort
IJTEE, volume-14 , Issue 1 (2018), PP 59 - 69
Published: 07 Jan 2018
by B. R. Qawasmeh, A. Al-Salaymeh, A. Swaity, A. Mosleh, S. Boshmaf from Mechanical Engineering Department, The University of Jordan, Amman 11942, Jordan
Abstract: The study aims to establish a comparison between different cars models (conventional and hybrid) from various manufacturers sold in the local Jordanian market. The aspects covered are the main performance parameters such as the output horsepower, hybrid system type used and the economic parameters including net present prices, miles travelled per gallon (MPG) and the payback period. In addition, we study the environmental aspect such as CO2 gas emissions. Moreover, some special aspects related to hybrid cars are studied to give better view of the new hybrid technology found in the world nowadays .Here, we collect data from previous studies and from the manufacturers’ data sheets as well as from local and international car experts and dealers. Then the data is arranged to deliver a clear view about the hybrid technologies. The study serves as a car selection guide, which contains the main parameters needed for all users and a technical review for researchers interested in the automotive industry of conventional/hybrid cars. As a result, the new hybrid car technology can be categorized into three main types (series, parallel, or series/parallel system), and into four main levels (Micro, Mild, Full, and Plug in). Toyota’s HSD (hybrid Synergy Drive also used by Nissan and Lexus) is a series/parallel hybrid system, while Honda’s IMA (Integrated Motor Assist) system and Hyundai hybrid system are from parallel hybrid type. Economically, over the full models range, Toyota Prius has the largest MPG of 51, which is constant throughout models range, thus having the highest annual saving of 421 JOD/year. However, Honda Insight and Honda Civic hybrid have lower payback periods due to their lower initial prices. Environmentally, Toyota Prius has the least CO2 emissions of 178 g/mile; also, HEVs have lower CO2 emissions than their conventional counterparts over all the models. Comparing HEVs’ output power to their conventional counterparts with the same engine size, HEVs have same or better output power. In summary, HEVs are recommended to replace the conventional cars, due to their ability of reducing CO2 emissions, fuel consumptions, and offering slightly better performance. read more... read less...
Keywords: Hybrid Cars, Conventional Cars, CO2 emission
IJTEE, volume-14 , Issue 1 (2018), PP 49 - 58
Published: 07 Jan 2018
by Khaled S. Al Qdah from Faculty of Engineering, Mechanical Engineering Department, Taibah University, Madinah 42435, KSA
Abstract: The aim of this work is to study the technological feasibility and economic viability of the electrification of small house lies in a farm 50km far away from Almadinah AlMunawwarah. Nowadays, solar powered air conditioning has witnessed an increased progress because air conditioning system is almost a must in every building in Saudi Arabia where the outside temperature in summer higher than 45◦ C. therefore, this paper consists of two parts: one to investigate the design and performance of solar powered air conditioning system as a case study integrated with photovoltaic (PV) system which consists of PV panels, solar charger, inverter and batteries. The second part is to study the feasibility to provide electricity for a farm lies in the remote area far 50 km from Almadinah. The first step in this project is the load calculations for the selected space including lighting, cooling and other necessary appliances. Based on the cooling load calculations for the specified room used as a case study, it was found the estimated cooling load about 1-ton refrigeration (3.52 kW), the photovoltaic (PV) system has been constructed and built with the necessary connections. Data logging system has been used to measure the temperatures at the main components in the cycle. The input powers for the system as well as the coefficient of performance (COP) for the system under Almadinah climatic conditions were measured along the day. The COP varies between 2.16 to 4.22 for the system and are in a good agreement with conventional system performance. Economically, the PV system found to be the optimal solution to provide the required load at an initial cost of 187,267 SR. The present work shows that the PV system has the potential to provide electricity for remote homes far from the grids with additional environmental benefit that otherwise not gained when using conventional fossil fuel read more... read less...
Keywords: Performance, PV, COP, Remote Areas, Climatic Conditions
IJTEE, volume-14 , Issue 1 (2018), PP 41 - 48
Published: 07 Jan 2018
by S. Abdul-Rahman, A. Badran from Mechanical Engineering Department, University of Jordan, Amman, 11942 Jordan
Abstract: A standalone hybrid PV/ wind energy system is proposed to be used to continuously power a submersible water pump from a selected well out of 55 production wells located at the Disi aquifer, South of Jordan. Each of these wells has a continuously-operating water flow rate of 288 m3 /h. Excess energy, if any, is to be stored in the form of a pumped water storage at the ground level near the well. Solar radiation and wind speed data for Al-Mudawara border meteorologicalstation, which was taken as a representative of the Disi water aquifer were collected and analyzed. Energy analysis was monthly made on the basis of average daily available energy. The performance of three PV/wind power plant scenarios was analyzed through the study of the underground water pumping wells using Life Cycle Cost (LCC) method. It was found that, for one scenario, the hybridization of a 16.5 MW is produced by PV power plant and 27.5 MW by wind power plant at Al-Mudawara site is the optimal scenario which is economically and technically feasible. It was found that the storage energy covered the load after implementation of the proposed project, the cost of 1 kWh of energy produced was estimated to be 0.16 $/kWh., and the system payback period was 4.5 years. read more... read less...
Keywords: Hybrid system, Off- Grid, Storage tank
IJTEE, volume-14 , Issue 1 (2018), PP 33 - 39
Published: 07 Jan 2018
by S.M.A. Rahman, A. Sara, R. Asmaa, S. Rasha from Sustainable and Renewable Energy Engineering, University of Sharjah, Sharjah 27272, United Arab Emirates
Abstract: The aim of this project is to design a portable solar thermoelectric refrigerator for people living in remote areas, or outdoor applications where electric power supply is absent. The design of the solar-powered refrigerator based on the principle of the thermoelectric module to create a hot side and cold side. Solar PV module is used to supply electrical energy to the thermoelectric module to generate hot and cold effects for heating and cooling application. A wellinsulated rectangular container made of aluminum is used as a cooling chamber. To enhance the cooling effect, heat sinks and electric fans are added to the hot side to cool down the thermoelectric modules. The system was able to reach 40 C in the cold surface of the TEM and 100 C as the refrigerant temperature and 300 C in hot chamber with 0.66 COP. An economic analysis is carried out to study the viability of this novel technique. Economic analysis reveals that the system has sufficient amount of saving due to renewable source of energy which is free and lower maintenance cost. One more major advantages of the proposed refrigerator is its longer lifetime that might reach up to 40 years read more... read less...
Keywords: Solar PV Module, Refrigerator, Thermoelectric Module, COP, Economic Analysis
IJTEE, volume-14 , Issue 1 (2018), PP 27 - 32
Published: 07 Jan 2018
by K. Hassouneh, S. Suleiman, and A. Al-Salaymeh from Architecture Engineering Department, School of Engineering, University of Jordan, Amman, 11942, Jordan Mechanical Engineering Department, School of Engineering, University of Jordan, Amman 11942 Jordan
Abstract: The main objective of this study is to conduct an Energy Auditing of The University of Jordan Hospital. This hospital is quite known, as one of Jordan’s leading hospitals in human resources and equipment; however, the energy consumption of the hospital over the past few years has proven to be highly expensive. This makes the saving on costs of energy consumption a high priority that cannot be ignored. Energy audit covers the three main sections of the hospital: the Emergency Building, the Clinics Building and the Main Hospital Building. The consumption of energy, which costs the hospital a total of 2,778,426 JD/yr., can be categorized into three main parts, the lighting system, the diesel fuel consumption, and the consumption of water. After analyzing the energy invoices, and visiting the site for inspection, a list of recommended solutions that are applicable to cut down the total energy bill were derived. The implementation of renewable energy was suggested and studied of which a solar water heating system was proposed. A study on photovoltaic cells technology was performed for a sample of guest's rooms, the number of panels needed was found. After that, a feasibility study was conducted. The initial costs, annual savings and payback periods of the suggested system were estimated by the current market prices. It is found that the energy auditing and the solutions would be very beneficial as it will save a total annual value of 346,853 JDs (12.5% of the current energy bill). read more... read less...
Keywords: Energy saving, energy audit, payback period
Performance Study of a Multi-Objective Mathematical Programming Modeling Approach for Energy Optimization in Building Envelopes
IJTEE, volume-14 , Issue 1 (2018), PP 17 - 26
Published: 04 Jan 2018
by Hussain H. Alzoubi, Mustafa Z. Ali, Yara M. Al Manaseer from College of Architecture and Design, Jordan University of Science and Technology, Irbid 22110, Jordan Faculty of Information Technology, Jordan University of Science and Technology, Irbid 22110, Jordan Faculty of Architecture and Design, Amman Al Ahliyya University, Amman 19328, Jordan
Abstract: Architecture is very responsive to the environmental and climatic factors which affect the built environment with unsteady state. Technology can be used to keep these factors under control by optimizing building design to fit with the surrounding environment and the energy needs. In addition, building envelopes play a major role in achieving thermal comfort for occupants and reducing energy consumption. Building envelopes energy optimization became a leading approach in the architectural research and implementation. This study hypothesizes that using solar shading devices with suitable design decisions of the fenestration affects the daylight level, solar heat gain, visual comfort, and thermal comfort for users. The main objective of this study is to examine the relationships between building envelope design and building energy efficiency through research and simulations. In addition, it explores which combinations of the design elements are the most efficient in terms of lighting and HVAC loads which gives the designers a variety of optimum design solutions to choose the architectural from. This research focuses on the implementation and effectiveness of shading devices, glass type, and window-wall ratio (WWR) in energy optimization through building envelope. The study used MATLAB software for the mathematical model simulation while Revit software was used for the model validation. The study found that south orientation for buildings associated with horizontal shading elements is the best solution in terms of cooling loads in summer. In winter, however, the optimal solution was south orientation with vertical shading elements in terms of heating loads and illuminance levels. read more... read less...
Keywords: Building envelope, Simulation, Energy efficiency.
IJTEE, volume-14 , Issue 1 (2018), PP 11 - 16
Published: 04 Jan 2018
by T. Kansara from UCL Energy Institute, London, UK
Abstract: This paper describes the transitional zones of modern buildings and the impact of raising their temperature. A transitional zone is described as none steady-state spaces like entrance lobbies, corridors, lift-lobbies and landings, which allow occupants to transition through to more steady-state spaces. This paper presents the results of a dynamic simulation, where a typical case study building is used for an intervention of 1-5ºC increases in indoor temperature on energy demand. The results show raising the temperature in the transitional zones can result in a saving of 0.63% per ºC reduction of cooling for the whole building. The recommendation of this paper is to investigate a broadening of the thermal comfort parameters of these communal areas not serviced by the ASHRAE-55: 2-13, or any other standard, in order to identify the potential for reducing electricity used for cooling. Applying sensible engineering design load calculations will ensure comfort conditions and energy use are treated separately to occupied zones. read more... read less...
Keywords: Transition Zones, Thermal Comfort, Energy Demand Reduction
IJTEE, volume-14 , Issue 1 (2018), PP 1 - 9
Published: 23 Jan 2018
by Isam Janajreh, Kamel Adouane, Mohammed Hussain from Masdar Institute of Science and Technology, Abu Dhabi, UAE
Abstract: The wind catcher potential for providing occupants comfort conditions is been investigated under trans-evaporative cooling for two-level simple dwelling in arid region. The wind catcher runs on the reverse chimney concept in which the upper wind is captured (by means of passive or active louvers) and is impregnated with moisture that consequently reducing its temperature and increasing its density. This results in a cold downdraft stream in the tower which is used to the conditioning of the dwelling space. This work uses a high fidelity computational fluid dynamics (CFD) of multiple species and two-phase flow to examine the performance of the wind catcher subjected to water injection in the form of mist of 10micron droplet size. The air flow is governed by the none-isothermal Navies-stokes equations which are coupled with energy equation in a conjugated heat transfer in accounting to the inner building walls and the convective conditions for the rest of the building. The water droplet is governed by the discrete phase that also in direct coupling with the continuous phase representing the wind. Flow parameters including velocity, temperature, relative humidity and droplets dispersion are evaluated and their distribution is presented. The setup is tested at different regional conditions manifested in the incoming wind speed, present relative humidity level and temperature sensitivity. Results show that in the average UAE summer conditions (42o C and 50% R. humidity) the role of wind catcher in evaporative cooling was deemed unimportant. However under pre-dehumidification near 25% R. humidity a significant temperature drop of 10 o C and reasonable R. humidity of near 60% can be obtained when integrating wind catcher to isolated dwellings. read more... read less...
Keywords: Wind catcher, cool tower, trans-evaporative cooling