Facing the growing problem of the electric power consumption in Egyptian residential building using building performance simulation program

Egypt has been experiencing recurrent power cuts especially at the summer, with the problem being made worse by the extra demands placed on the electrical grid by the advent of the holy month of Ramadan. Electricity shortages are now a problem in Cairo, Alexandria, Sohag, Qena, Luxor, Aswan, and Nubia, as well as in the Nile Delta governorates of Beheira and Qalioubiya. The aim of this study is to develop a model for the Egyptian residential building using Building Performance Simulation Program and make sensitivity analysis on some variables effecting the electric power consumption in order to help faceting the growing problem in Egypt. The model was created using the IES-VE 2012 (Integrated Environmental Solution ). The simulation model was verified against the survey data for the Egyptian apartment and same model simulated using energy Plus simulation tool. The results of the program describing different situations for energy using profile for the air conditions, lighting and equipments in respect to building layout and construction climate and pattern of use. This model can be used in the future to help in reducing the electric power consumption in the residential building

Discrete Half-Logistic Distribution: Statistical Properties, Estimation, and Application

This article presented a novel discrete distribution with one parameter derived by the discretization approach and called the discrete half-logistic distribution. Its probability mass function and hazard function have different shapes. A variety of its statistical properties, including moments, probability generating function, incomplete moments, and order statistics, were determined mathematically. Maximum likelihood, moments, and proportion estimation methods were used to estimate its parameter. A simulation study conducts to check the various estimating method’s performance. By using a real data set, its flexibility is assessed. Lastly, it can model count data sets in a way that is compared with other distributions that are already in the scientific literature

Energy and indoor environmental performance of typical Egyptian offices : survey, baseline model and uncertainties

Egyptian electricity demands have increased in recent years and are projected to grow further with significant economic and social impacts. Recently, mandatory and voluntary building codes based on international standards have been increasingly adopted. The performance of existing Egyptian buildings is not well understood making the impact of these new codes uncertain. This paper aims to provide insights into existing Egyptian building performance, and elaborate a process for developing a representative model to assist in future policy. The work presented is for office buildings but intended to be widely replicable. An energy survey was carried out for 59 Egyptian offices, categorised by building service type, it was observed that energy use increases as building services increase, and existing Egyptian offices use less energy than benchmarks. A more detailed investigation for a case study office was carried out, to inform detailed model calibration. This provided insight into energy use, thermal comfort and environmental conditions, and revealed high variability in behaviours. A calibrated model was created for the case study office, then a baseline model and input parameter sets created to represent generalised performance. Future uses including assessment of the impact of codes are discussed, and further replication potentials highlighted

The energy and indoor environmental performance of Egyptian offices : parameter analysis and future policy

Buildings are a significant contributor to the rapidly increasing electricity demand in Egypt which is straining the existing supply network causing economic and social impacts. There are current initiatives aimed at improved building performance including adoption of international standards. The performance of existing Egyptian buildings is not well understood making the impact of these international standards uncertain. This paper provides insight into performance of current Egyptian office buildings through a multi-building energy survey and a detailed case study. The most common office type in the survey has natural ventilation and local cooling. A process to capture observed performance in a representative model and input parameter set is presented. The model is used to investigate performance impacts of parameters including: location, weather, building envelope, intensity of occupancy, behaviour, and installed systems including the HVAC strategy. HVAC strategy was identified as the most significant factor. Typical Egyptian offices with natural ventilation and local cooling systems under personal control have electricity demand less than 50% of centrally serviced buildings. System efficiencies (HVAC, lights, equipment) and occupant behaviour (e.g. use of systems, temperatures) were also identified as significant factors, each with potential of around 30% saving compared to current typical offices. Possible policy measures to promote energy efficient systems and energy conscious behaviour are proposed which together can reduce the energy demand of typical offices by 50%. Trade-offs between energy use and indoor environmental quality (IEQ) are discussed

Nanofluid impingement jet heat transfer

Experimental investigation to study the heat transfer between a vertical round alumina-water nanofluid jet and a horizontal circular round surface is carried out. Different jet flow rates, jet nozzle diameters, various circular disk diameters and three nanoparticles concentrations (0, 6.6 and 10%, respectively) are used. The experimental results indicate that using nanofluid as a heat transfer carrier can enhance the heat transfer process. For the same Reynolds number, the experimental data show an increase in the Nusselt numbers as the nanoparticle concentration increases. Size of heating disk diameters shows reverse effect on heat transfer. It is also found that presenting the data in terms of Reynolds number at impingement jet diameter can take into account on both effects of jet heights and nozzle diameter. Presenting the data in terms of Peclet numbers, at fixed impingement nozzle diameter, makes the data less sensitive to the percentage change of the nanoparticle concentrations. Finally, general heat transfer correlation is obtained verses Peclet numbers using nanoparticle concentrations and the nozzle diameter ratio as parameters

Heat transfer due to impinging double free circular jets

The heat transfer and fluid flow between a horizontal heated plate and impinging circular double jets were studied experimentally. The parameters investigated are the Reynolds number of each jet and jet-to-jet spacing. Experiments are carried out covering a range for Reynolds number from 7100 to 30,800 for each jet, the dimensionless jet-to-jet spacing from 22.73 to 90.1. During experimental phases, the right jet Reynolds number was higher than the left jet Reynolds number. The isothermal contours were plotted for different cases as well as the distribution of water film thickness over the heated plate. The results indicated that increasing the Reynolds number of one jet than the other increases both local and average Nusselt numbers. In addition, increasing the jet-to-jet spacing at the same Reynolds number increases the average Nusselt number

Natural convection heat transfer from an isothermal horizontal square cylinder

Laminar natural convection from a horizontal isothermal square cylinder is numerically investigated. The study covered a range of Rayleigh number, Ra from 103 to 106. A computer program is developed to solve the continuity, momentum and thermal energy equations together with their boundary conditions by using a finite volume method. Streamlines and isotherms were generated to describe the flow around the square cylinder. The local and average Nusselt numbers are calculated and plotted over the four sides of the square cylinder. The numerical results were correlated and compared with previous work