Thermodynamic Analysis of a Gas Turbine Power Plant Modelled with an Evaporative Cooler

Performance of a gas turbine is mainly depends on the inlet air temperature. The power output of a gas turbine depends on the flow of mass through it. Inlet air cooling increases the power output by taking advantage of the gas turbine’s feature of higher mass flow rate when the compressor inlet temperature decreases. This is precisely the reason why on hot days, when air is less dense, power output falls off. A rise of 1°C temperature of inlet air decreases the power output by 1%. In this paper the performance enhancement of gas turbine power plants by cooling the compressor intake air with an evaporative cooler is studied. This study investigated the effect of inlet air cooling system on the performance of an existing gas turbine power plant in Nigeria. The results show that for each 5oC decrease of inlet air temperature, net output power increases around 5-10% and the first and second law efficiencies increase around 2-5%. It is shown that the amount of this increase is higher when the pressure ratio is high and turbine inlet temperature is low. The results of this study shows that retrofitting of the existing gas turbine plant with inlet air cooling system gives a better system performance and may prove to be an attractive investment opportunity to the Nigeria government and stakeholders of the plant

Occupational mobility in engineering profession (craftman and artisan) in Oyo State, Nigeria.

This paper evaluate occupational mobility in engineering professional in Oyo State of Nigeria with the goal assessing causes and readiness of the professionals to return to the profession when the hindering factors are removed as well as sufficiency of the survey instrument in addressing the research problems. The study was conducted using a well structured questionnaire administered in 20 local government of Oyo State, Nigeria representing the sample space of 0.424. The Cronbach’s alpha of the reliability test of 0.453 was returned for the scale mean statistics of 11516.83 and variance of 0.0000007 showing that the survey instrument was sufficient and could be relied upon. The result of the socio economic analysis showed that 80% of the respondents were married while (15%) were single and the rest (5%) were divorced. The age distribution of the respondents ranged between greater than 50 years groups (12%) and 30 -39 years group (39%).The result of the analysis of job characteristics of the respondents showed that the longer the year of graduation, the lesser the number of graduates still in the business. The cross table analysis of the socio-economic indices with the job status of the respondents showed that marital status and level of education does not have significant effects on the job status of the respondents (whether still practicing or not) because 1.454 and 5.223 returned for both marital status and level of education are not significant (P<0.05). Also, the contingency table analysis of the effects of the skill acquisition methods showed that more of the respondents who acquired their skill via Technical School (70%) are willing to go back to the professions. However, for those who acquired their skill through Learning/artisanship, less than average (32%) of the respondents are ready to return to the profession. Lastly, the establishment of the regression model for the relationship between the proportion of the people wishing to go back to the profession and year of practicing the profession provide a necessary impetus for addressing the Job mobility problem faced by the profession

Turbidity and Urine Turbidity: A Mini Review

Turbidity, the measurement for impurity and the opposite phenomenon of clarity, is described as the reduced transparency of a liquid caused by the existence of undissolved matter in the form of suspended particles. The permissible volume of light through the liquid, or light that is not dispersed or absorbed but emitted through the liquid and propagated toward the observer, provides a foundation for the analysis of various subject matters, such as liquid mass concentration and impurity identification. The turbidity of urine is increased by the presence of cellular debris, cast, and, in some cases, crystal and other debris in the urine. Blood (both red and white blood cells), hemoglobin, cholesterol, albumin, leukocyte esterase, nitrites, ketones, bilirubin, and urobilinogen are all substances that are not expected to be found in urine, the presence of which can increase urine turbidity. Owing to the principle of turbidimetry, it is not the detection of turbidity that is the cause of the turbid state of urine but the presence of suspended particles and a rough estimate of the number of suspended particles in urine. This research exposes the different methods of obtaining the turbidity of a liquid sample and the working principles of turbidimetry and nephelometry

Smart Toilets and Toilet Gadgets in Sustainable Smart Cities: An Overview of Personal Health Monitoring

Healthcare as a service in most developed countries has advanced more than just electronic medical records (EMR), automated hospital experience, hospital information systems, and the like of it. Healthcare services have attained the height of remote surgery, computer-aided surgery, and remote patient monitoring and care due to the advancements in information and communication technology coupled with the advancement in artificial intelligence (AI) ability on the Internet of things. The use of smart gadgets in the toilet capable of collecting data relevant to healthcare makes the gadget a personal health monitoring device, which is a medical care supplement to traditional health monitoring. This provides an effective, non-invasive, nondestructive, low-cost, accuracy, and timesaving method of conducting health monitoring on the user in real time

Modification to Metal Matrix Composites Nomenclature

Naming Metal matrix composite (MMC) is very crucial to both the developer and the end users. It is an indication of what the developer put together which goes a long way in assisting the end user in selecting from myriad of available MMCs. The existing nomenclature put forward by Aluminium Association identified the matrix, reinforcement, percentage composition and the form of reinforcement but left out the particle size of the reinforcement. The particle sizes have been found to have significant effect on the properties of MMC and should be included in the adopted naming system. This paper revised the existing standard from ‘Matrix/reinforcement/volume%form

Performance Evaluation of a Centrifugal Pump with different Impeller Materials

Many factors affect the performance characteristics of a pump. One of these is the impeller material. This paper is on the effect of impeller material on the operating characteristics of a centrifugal pump. The impeller materials used were cast iron, bronze and zinc. Cost, pumping efficiency, pressure head and power consumption are the factors that were taken into consideration. The results from the test, showed that the impeller made of zinc material was found to be more efficient (48.24%) and required the most power (3.38bhp). The zinc impeller was the least expensive to manufacture and pumped better head. The zinc impeller however failed at (very) high pump speed due to the fact that its strength could not match up with the pump speed. The cast iron impeller on the other hand, required the least power (0.86bhp) to run but pumped the least head (6.25m) and was more efficient (46.35%) than the bronze impeller; this was majorly due to cavitation and friction losses. The bronze impeller pump was the least efficient (38.79%), the most expensive to manufacture but pumped more head (8.50m) than the cast iron impeller and required more power (2.32bhp) than the cast iron impeller

SOME PHYSICAL PROPERTIES OF SELECTED VEGETABLE

Physical attributes of biomaterial are needed as parameter in computer simulation of deformation of Agricultural and Food material under compressive loading using Discrete Element method. In this study, two vegetable namely chilli pepper (Capsicum frutescens) and bell pepper (Capsicum annum) were selected and some physical properties (mass, major diameter, intermediate diameter, minor diameter, and volume) at 10.88% w.b and 9.79% w.b moisture content were determined using standard methods. The results of the study show that the frequency distributions of each of the size of the two pepper varieties follow a normal distribution curve. The average geometric mean diameter and sphericity of bell pepper are 43.94mm and 64.23%while that of chilli pepper are 25.55mm and 86% respectively The mean mass, volume, true density and bulk density for bell pepper were 29.91g, 27.75cm3, 1.117gcm-3 and 0.52gcm-3 while that of chilli pepper were 8.4g, 8.23cm3, 0.90gcm-3 and 0.41 gcm-3 respectively. These data are useful in the design and development of handling and processing machine

DESIGN AND PERFORMANCE ANALYSIS OF A MODEL PICO SIZE PELTON WHEEL TURBINE

A hydropower generation is an ancient but evergreen energy source that utilises mechanical energy of water strolling down from an elevated head to drive an electric generator thus producing electricity. Small Hydropower (SMH) turbines are rotated by a relatively low-pressure head and usually generates low energy output usually referred to as mini, micro or Pico energy range. Pelton Turbines are generally found to be amongst the most suitable for a low flow power generation. This study focuses on the design of a model Pico size Pelton Wheel modified to use the velocity of water harvested from rooftops during rainfall for the purpose of supplementing energy supply. By the design, the rainwater from the building rooflines are collected and passed through the downspouts into an elevated tank and then the height of the bottom of the tank gives the required head (pressure) to spin the microturbine and then generates a Pico level energy. The Pico size hydropower system directly connected to a small, variable speed, an electric generator which is capable of supplying the power needed for some minimal but very essential functions like charging handsets, mini gadgets and low energy lighting purposes. Specific design calculations, as well as analysis of the model Pico size energy system, was performed to ascertain the feasibility of the design meeting some specified energy needs, thus reducing energy poverty

Anticorrosion Effect of Silicon Nitride and Zirconium Diboride Composite on Ni–P– Zn Electroless Deposition on Mild Steel

Electroless nicked-based deposition on mild steel surface from a nickel–zinc phosphate bath with NiSO4·6H2O, ZnSO4·7H2O, and NaH2PO2·H2O salt in the presence of silicon nitrides and zirconium diboride as additives at a constant time was studied. The structural evolution of electroless deposited mild steel surface was characterized for crystal change formation using a scanning electron microscope (SEM) and elemental quantification done using energydispersive spectroscopy (EDS). The electrochemical corrosion analysis of the deposited mild steel with and without composite additives was analyzed using linear polarization resistance and open circuit potential in both H2SO4 and NaCl solution. From the results, significant presence and the effect of wt% of additives were noticeable on the electroless mild steel surface. Ni–P–Zn in the presence of 10ZrBr2 and 10Si3N4 actively provide an induced weight gain of 0.0974 g and 0.0973 g, respectively. A correspondent, 0.034 g/m2 coating per unit area of zirconium diboride additives, was obtained against 0.030 g/m2 for silicon nitrides. The structural evolution shows proper homogeneous crystal formation and stable packed additive concentrated at the lattices with EDS showing the presence of induced peak. From the corrosion assessment result, electroless deposited mild steel with Ni–P–Zn–10ZrBr2 and Ni–P–Zn– 10Si3N4 with optimum particle concentration shows better corrosion resistance performance with a corrosion rate of 0.5048 mm/year, and 5.1347 mm/year, as against the unadditive deposition with 11.393 mm/year in NaCl solution

Modelling some ergonomic parameters with machine parameter using hand powered maize sheller

The economic situation in most developing countries have left farmers and processors operating at the small scale, hence the use of automated and electric power driven equipment is limited to the few large scale processors. The effect of the ergonomic parameters namely; weight, age, height and arm length in relation to the resulting efficiencies; shelling efficiency, cleaning efficiency, mechanical damage and percentage sieve loss of a hand powered Maize Sheller incorporating a blower were studied using a non linear regression analysis. The study was with a view to developing a model for the performance of the hand powered maize sheller. The power transmission increases the speed of the blower for high cleaning efficiency. Preliminary studies were carried out to determine the ergonomic data of operator, and moisture content and grain/chaff. The results on studies with maize with 12% dry basis moisture content and grain/chaff ratio of 3.04:1 show that weight has the most significant effect (p<0.05). The mean of the shelling efficiency, cleaning efficiency, sieve loss and mechanical damage of the machine are 94.3, 96.4, 2.3 and 5.23% respectively and the coefficient of determination for the regression equations relating the ergonomic parameters to machine efficiency and parameters ranges from 0.29 to 0.86 with quadratic regression obtained. Equations were derived to relate the variables and an approximate solution was obtained from a particular example, which validates the theoretical prediction with known results