Browsing by Author "Akpenpuun, Timothy"
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Item Analysis of Heat and Mass Distribution in a Single- and Multi-Span Greenhouse Microclimate(Agriculture, 2021-09-16) Akpenpuun, TimothyRecently, heat and mass distributions within a greenhouse were assumed to be homogeneous. Heat is gained or lost in absolute terms, and crop contribution in a greenhouse or its effect is not considered. In this study, statistical analyses were conducted to establish the significance of heat and mass variation at sensor nodes in two single-span and multi-span greenhouses. Three greenhouses were used in this study, 168 m2 floor area a single-layered (SLG), double-layered (DLG) single-span gothic roof type greenhouses, and 7572.6 m2 floor area multi-span greenhouse (MSG). The microclimatic parameters investigated were temperature (T), relative humidity (RH), solar radiation (SR), carbon dioxide (CO2), and vapor pressure deficit (VPD). To check their horizontal distribution, all microclimate data collected from each sensor node in each greenhouse were subjected to descriptive statistics and Tukey honestly significant difference (HSD) test. The lowest minimum temperatures of 2.93 C, 3.33 C and 10.50 C were recorded at sensor points in SLG, DLG, and MSG, respectively, whereas the highest maximum temperatures of 29.17 C, 29.07 C and 27.20 C were recorded at sensor point, in SLG, DLG, and MSG, respectively. The difference between the center and the side into the single-span was approximately 0.88–1.0 C and in the MSG was approximately 1.03 C. Significant variation was observed in the horizontal distribution of T, RH, SR, and VPD within SLG, DLG, and MSG. Also significant was CO2 in the MSG. Estimating the energy demand of greenhouses should be done based on the distribution rather than assuming microclimatic parameters homogeneity, especially for T, with VPD as a control parameter. Such estimation should also be done using a crop model that considers instant changes in air and crop temperature.Item ANALYSIS OF HEAT AND MASS DISTRIBUTION IN A SINGLE- AND MULTI-SPAN GREENHOUSE MICROCLIMATE(Agriculture MDPI, 2021-09-16) Akpenpuun, TimothyRecently, heat and mass distributions within a greenhouse were assumed to be homoge neous. Heat is gained or lost in absolute terms, and crop contribution in a greenhouse or its effect is not considered. In this study, statistical analyses were conducted to establish the significance of heat and mass variation at sensor nodes in two single-span and multi-span greenhouses. Three greenhouses were used in this study, 168 m2 floor area a single-layered (SLG), double-layered (DLG) single-span gothic roof type greenhouses, and 7572.6 m2 floor area multi-span greenhouse (MSG). The microclimatic parameters investigated were temperature (T), relative humidity (RH), solar radiation (SR), carbon dioxide (CO2 ), and vapor pressure deficit (VPD). To check their horizontal distribution, all microclimate data collected from each sensor node in each greenhouse were subjected to descriptive statistics and Tukey honestly significant difference (HSD) test. The lowest minimum temperatures of 2.93 ◦C, 3.33 ◦C and 10.50 ◦C were recorded at sensor points in SLG, DLG, and MSG, respectively, whereas the highest maximum temperatures of 29.17 ◦C, 29.07 ◦C and 27.20 ◦C were recorded at sensor point, in SLG, DLG, and MSG, respectively. The difference between the center and the side into the single-span was approximately 0.88–1.0 ◦C and in the MSG was approximately 1.03 ◦C. Significant variation was observed in the horizontal distribution of T, RH, SR, and VPD within SLG, DLG, and MSG. Also significant was CO2 in the MSG. Estimating the energy demand of greenhouses should be done based on the distribution rather than assuming microclimatic parameters homogeneity, especially for T, with VPD as a control parameter. Such estimation should also be done using a crop model that considers instant changes in air and crop temperature.Item ASSESSING THE EFFECTIVENESS OF MORINGA OLEIFERA SEED AS A COAGULANT IN DOMESTIC SEWAGE TREATMENT(Research Journal of Engineering and Environmental Sciences, 2017-01-20) Akpenpuun, TimothyThe effectiveness of Moringa oleifera seed as a natural coagulant for domestic sewage treatment was investigated in this study. A completely randomized design (CRD) was adopted for the treatment process. The treatments included the control culture (no-Moringa seed), 2 g, 4 g, and 6 g of Moringa oleifera. Physical, bacteriological and chemical properties of domestic sewage were investigated before and after treatment. The turbidity, water hardness, suspended solids, dissolved solids, biochemical oxygen demand (BOD) and chemical oxygen demand (COD) showed reductions while dissolved oxygen (DO) showed some increase indicating that some level of treatment was achieved. There was no significant difference between the pH, BOD and COD obtained for the 2 g, 4 g and 6 g treatments. The study has revealed that Moringa oleifera as a natural coagulant shows potential in the treatment of the domestic sewage.Item ASSESSING THE EFFECTIVENESS OF MORINGA OLEIFERA SEED AS A COAGULANT IN DOMESTIC SEWAGE TREATMENT(Research Journal of Engineering and Environmental Sciences, 2017-02-20) AKPENPUUN, Timothy; Adeniran, K; Wasiu, R; Akpenpuun, TimothyThe effectiveness of Moringa oleifera seed as a natural coagulant for domestic sewage treatment was investigated in this study. A completely randomized design (CRD) was adopted for the treatment process. The treatments included the control culture (no-Moringa seed), 2 g, 4 g, and 6 g of Moringa oleifera. Physical, bacteriological and chemical properties of domestic sewage were investigated before and after treatment. The turbidity, water hardness, suspended solids, dissolved solids, biochemical oxygen demand (BOD) and chemical oxygen demand (COD) showed reductions while dissolved oxygen (DO) showed some increase indicating that some level of treatment was achieved. There was no significant difference between the pH, BOD and COD obtained for the 2 g, 4 g and 6 g treatments. The study has revealed that Moringa oleifera as a natural coagulant shows potential in the treatment of the domestic sewage.Item BUILDING ENERGY SIMULATION MODEL APPLICATION TO GREENHOUSE MICROCLIMATE, COVERING MATERIAL AND THERMAL BLANKET MODELLING: A REVIEW(2022-09-11) Akpenpuun, TimothyThis review documents the present knowledge and knowledge gap in applying building energy simulation (BES) dynamic models to greenhouses. The focus of this review is to compile the literature on the BES dynamic model of greenhouse microclimate, covering materials, energy requirements and thermal blankets using the Transient System Simulation version 18 (TRNSYS 18) software. Fifty-two journal articles, mostly Science Citation Index (SCI) and Scopus index journals, on BES development and simulation of greenhouse microclimate, greenhouse energy requirement, covering materials and thermal blankets were reviewed. These researchers sought to optimise greenhouse crop production. The main features of the TRNSYS 18 software for BES development are outlined; each research consulted for this review successfully developed, simulated and validated its BES. However, none of these developed models included the vapour pressure deficit (VPD) as a greenhouse microclimate factor, an essential climate parameter. In conclusion, this study demonstrates that applying a BES developed using TRNSYS has excellent potential to optimise greenhouse crop production and help adapt appropriate climate control strategies and energy-saving techniques. However, it is recommended to include VPD in future BES model development.Item CERAMIC WARE WASTE POTENTIAL AS CO-BALLAST IN DENSE MASONRY UNIT PRODUCTION(2015) Akpenpuun, TimothyCeramic ware waste applicability as coarse aggregate was considered in this study for dense masonry unit production. The waste was crushed into 1.4 mm particle size and mixed with natural fine aggregate in the ratio 2:3. Portland ordinary cement, aggregate, and water mix ratio was 1:7:0.5. Masonry units produced were cured for 7, 21, and 28 days prior to compressive test. Result shows that curing age have a significant impact on all the compressive strength indices inspected except for Young’s modulus. Crushing force and the compressive strength of the ceramic-natural fine aggregate blocks increased by 11.7 – 54.7 % and 11.6 – 59.2 % respectively. The highest ceramic-natural fine block compressive strength at yield and peak, 4.97 MPa, was obtained after 21 days curing age. Ceramic aggregate introduced into the dense blocks improved the suitability of the blocks for construction purposes.Item CHARACTERIZATION OF CASTOR BIODIESEL BLENDED WITH CONVENTIONAL DIESEL FUELS(Nigeria Institution of Agricultural Engineers (NIAE), 2020) Akpenpuun, TimothyCompression Ignition Engines have proved its usefulness in agriculture, transportation, and power sector. In this research, the physicochemical properties of different blends of castor biodiesel were compared with conventional diesel fuel. Samples of the castor biodiesel prepared using transesterification processwere blended with the conventional biodiesel in different mixed ratios, namely B5, B10, B15, B20, B25,B50 to B100. The physicochemical properties, including density, flash point and kinematic viscosity were determined following standard and international procedures (ASTM). Results show that the B100 has higher density, kinematic viscosity and flash point compared to the conventional diesel at 280 °C. But the calorific value was lower in comparison. A gradual decrease in the density, flash point and kinetic viscosity were observed with a decrease in the biodiesel blends from B100 to B5. This implies that the castor biodiesel can be used as a close substitute for the conventional diesel fuel and has substantial advantages, especially in area of greenhouse control and energy security. Keywords: Castor biodiesel, Diesel fuel, Analysis, Diesel engine and Physico-chemicalItem CLIMATE CHANGE EFFECT ON GRAIN CROPS YIELDS IN KWARA STATE, NIGERIA(Nigerian Institution of Agricultural Engineers, 2015-10-15) Akpenpuun, TimothyItem DESIGN AND FABRICATION OF A SIMPLE PEDAL OPERATED CASSAVA GRATER SUITABLE FOR RURAL DWELLERS(Journal of Applied Science and Environmental Management, 2019-06-20) Akpenpuun, TimothyFood crop in Nigeria is mainly produced by farmers in the rural areas where petrol/diesel for operating engine, electricity and machines for processing agricultural produce are lacking and this usually result to loss of agricultural produce on the farm before and after harvesting. This study was embarked upon to develop a simple pedal operated cassava grater for rural dwellers. The cassava grater was fabricated using locally available materials mainly hardwood for constructing the frame, grating chamber (hopper), grating roller and the outlet. Iron rod of 20 mm in diameter (mild steel) for the shaft, three roller bearings, driven and driver pulleys, belt, bicycle pedal and galvanized sheet (2 mm in thickness) for the grating surface on the grating roller. The frame of the cassava grater was 540 mm wide, 1200 mm long and 1050 mm high and the grater is portable. The grating chamber was 420 by 440 mm at the top where the cassava is fed into the grater and 220 by 440 mm at the bottom inside which the grating roller (190 mm diameter and 300 mm long) grate the cassava into granules. The grating efficiency and capacity of the grater were 90.91% and103.7 kg/h, respectively. The cassava grater could be used for grating cassava tubers in rural areas where electricity and petrol are lacking.Item DETERMINATION OF OVERALL HEAT TRANSFER COEFFICIENT FOR GREENHOUSE ENERGY-SAVING SCREEN USING TRNSYS AND HOTBOX(Biosystems Engineering, 2022-03-08) Akpenpuun, TimothyThe high energy consumption in the greenhouse during the winter season necessitates the development of various thermal screens for energy-saving purposes. However, there is limited data on the precise properties of thermal screens, while little research has investigated a methodological approach for measuring the screen's energy-saving capacity for greenhouse energy efficiency. This research aims to determine the thermophysical, radiative, and aerodynamic properties of selected commercial greenhouse thermal screens. The transient system simulation (TRNSYS) model was used to simulate the heat flux and derive the thermal retention qualities of the thermal screens through their measured properties. The model was validated by comparing the simulated and experimental heat transfer coefficients, expressed as the overall heat transfer coefficient (U-value), thereby, determining the thermal retention of the screens. In addition, the simulated U-value was compared to the experimental U-value in material permeability to investigate the influence of screen porosity on heat loss. The statistical analysis t-test was conducted to compare the U-values obtained from the simulation and the experimental hotbox. The simulated Uvalues (for computed permeability) indicated that samples M1 and M3 exhibited the lowest U-value of 4.4 W m 2 K 1, while white polyester, Luxous, PH-super, PH-66, M2, Clima45 (0), and New-Lux showed higher U-values of 82%, 105%, 161%, 123%, 41%, 102%, and 118%, respectively. Because of their low material porosity, M1, M2, and M3 samples showed better greenhouse thermal retention over others. Conclusively, the permeability features of the greenhouse energy screen materials have a substantial impact on their U-values.Item DEVELOPMENT AND PERFORMANCE EVALUATION OF A MODIFIED AFRICA BUSH MANGO (Irvingia gabomensis) CRACKER(Journal of Applied Science and Environmental Management, 2019-01-27) Akpenpuun, Timothy; Akpenpuun, TimothyAn African bush mango cracker was modified and fabricated to address the challenges of the conventional method of cracking nuts which involves striking the nut. The tedious nature of this process constitutes a major setback which restricts the production to a very small scale. The cracker consists of a frame, cracking table, slider– crank mechanism, hopper, feed chute, slot, cracking unit electric motor and reduction gear. The machine was evaluated with respect to throughput capacity and cracking efficiency at five moisture content levels (13, 15, 17, 20 and 25%) moisture content (MC) dry basis. At 13% MC; the output capacity was 7.13 kg/hr and cracking efficiency was 98% while at 15% MC; the output capacity and cracking efficiency reduced to 7.04 kg/hr and 96% respectively. Similarly, at 17% MC; output capacity and cracking efficiency further reduced to 7.02 kg/hr and 95% respectively while at 20% MC; the output capacity and cracking efficiency were reduced to 6.74 kg/hr and 93% respectively. There was a similar trend when the test was performed at 25% MC, as the output capacity and cracking efficiency showed a further reduction to 6.50 kg/hr and 90% respectively. These results were different from the old cracker that had throughput capacity and cracking efficiency of 4.32 kg/hr and 70% respectively. A significant trend was established which showed that as the moisture content of the nuts decreases, machine performance increases. Based on these results, drudgery and other hazards associated with manual cracking of the African bush mango are eliminated, the machine saves time and made processing of the seeds easier.Item DEVELOPMENT AND PERFORMANCE EVALUATION OF A POULTRY WASTE MANAGEMENT TECHNIQUE USING GRAVITY SAND FILTER(Arid Zone Journal of Engineering, Technology and Environment, 2017-08-01) Akpenpuun, Timothy; Akpenpuun, TimothyThe research aimed at developing and evaluating a poultry waste management technique using gravity sand filter. Poultry waste slurry prepared in a mixing tank was intermittently applied uniformly to the surface of a filter bed using a spreader as dosing technique. Two different types of configurations were designed for the filter bed. Single media bed consisted of 150mm depth of silica sand with average particle diameter of 0.5mm. Dual media bed consisted of 100mm depth of granulated charcoal with average particle diameter of 1.0mm and 50mm of silica sand with average particle diameter of 0.5mm. Design considerations important to achieving this level of treatment include; pretreatment, media characteristics, hydraulic and organic loading rates and filter dosing techniques. Each sand filter configuration was operated daily for a period of 12days. The following data were collected on a daily basis: Volume of effluents (mm3), hydraulic residence time (Hours), unit filter run volume (m3/m2), filtration rate or filtration velocity (mm/hr). Head loss on the filter was calculated using Carmen-Kozeny equation for uniform sand bed. Laboratory investigations showed that effluent from the filter had biological oxygen demand (BOD5), total suspended solids (TSS), total dissolved solids (TDS), and turbidity range between1.98 – 12.08 mg/L, 20.75 – 30.20 mg/L, 29.40 – 34.40 mg/L and 5.10 – 6.20 NTU.Item DEVELOPMENT OF A GREENHOUSE ROOF CLEANER(Journal of Agricultural Engineering and Technology, 2011) Akpenpuun, Timothy; Mijinyawa, YahayaItem DEVELOPMENT OF A PUSH-TYPE LIQUID FERTILIZER AND PESTICIDE SPRAYER(Nigerian Journal of Pure & Applied Sciences (NJPAS), 2021-05) Akpenpuun, TimothyLow yield, insect, pest and weeds competing with crops are challenges in crop production systems in Nigeria. This research was carried out to design and developed a push-type wheel operated liquid fertilizer/pesticide sprayer. The materials used for fabrication were selected based on the design assumptions, calculations and sourced locally. The sprayer was mechanically operated through the rotating shaft of the cartwheels using a slider-cranks mechanism. An accumulator was provided to create the required pressure of continuous spraying action. The sprayer possesses two tanks of 16 L each, a wheel, a coup-able stand, eight nozzles and an adjustable height depending on the crop height. The sprayer can cover 4.8 hectares per day, effective field capacity of 1.13 ha/h, theoretical field capacity of 1.24 ha/h. and field efficiency of 91%. The developed sprayer consumes less time, cost effective, high efficiency and the users will just have to pull the cart and the whole mechanism will be operated with ease.Item Development of Battery Operated Evaporative Cooling System for Storing Perishables(The Journal of the Association of Professional Engineers of Trinidad and Tobago, 2017-06-13) Akpenpuun, TimothyA study was conducted to develop a battery operated evaporative cooling structure for storing perishable fruits (pears). The structure consists of a cooling chamber made of aluminium which is inserted inside the galvanized steel interspaced with river bed sand of 7cm. The interspace soil is constantly wetted with water at room temperature to keep the soil moist condition. The other components attached are fan blades which are connected to 12 voltage battery and control by on and off switch to reduce temperature and increase relative humidity of air, electric wires and battery holder. The fan is designed in a way to suit the required operation. It consists of a stator (stationary part) and the rotor (rotary part). The fan blades are attached to the rotor which results in blowing of air due to electromagnetic induction. The capacity of the cooling chamber, amount of air moved in one revolution and fan pressure were 14,888,367mm3, 95.5 rpm and 14.96N/m2, respectively. Freshly harvested but matured pears were used for the experiment. The temperature and relative humidity were monitored on daily bases. The mean temperature in the storage structure and ambient were 24.93°C and 31.14°C respectively, while the mean relative humidity in the ECS and ambient were 89.5% and 61.14% respectively. Results showed that the constructed evaporative cooling structure (ECS) was able to maintain store produce at the temperature close to room temperature.Item EFFECT OF BULARAFA (DIATOMACEOUS EARTH) TREATMENT ON THE GERMINABILITY OF STORED COWPEA VARIETY (IT96D-610K(2018-08-15) Akpenpuun, TimothyItem Effect of Double-T and V-shaped Pipe Configurations and Perforations on the Quality of Chicken Litter Compost(FUOYE Journal of Engineering and Technology, 2019-03-01) Akpenpuun, TimothyLivestock waste management has received much attention because of the huge volume and instability. One of the good management practices adopted to address this menace is composting. This study examined the effect of specialized passively aerated composters on some physicochemical properties of chicken litter. The composter is made up of six double T and V shaped pipe with three different perforation diameters of 15, 20 and 25 mm. Pile configuration of the developed composters had marked effect on total nitrogen content (p 0.05) of the compost subjected to 90 days composting time. The composters had uniform air distribution as pile temperature was not significantly affected by pile configuration, perforation size, and their interactions. Furthermore, both T and V shaped pipe structures reached a thermophilic temperature of 49.0 and 67 oC respectively and the compost stabilized in the 12th week. From the agronomic point of view, V-shaped pipe outperformed double inverted T pipes with perforation sizes of 15 and 20 mm. Overall result from this study suggests that double-T and V-shaped composters are feasible composting systems that can enhance biodegradation, maturation, and stability of chicken litter.Item EFFECT OF ENVELOPE CHARACTERISTICS ON THE ACCURACY OF DISCRETISED GREENHOUSE MODEL IN TRNSYS(Journal of Agricultural Engineering, 2022-06-30) Akpenpuun, TimothyTRNSYS is a standard tool recently used to model and simulate greenhouse energy demand and utilisation using building energy simulation (BES). Previously, a single thermal point was used for validation, ignoring the distribution of greenhouse climate parameters, especially the temperature. Temperature variation often leads to thermal stratification, prompting researchers to propose volume discretisation in dynamic greenhouse simulations. In this context, the effect of envelope characterisation on the accuracy of the discretised TRNSYS BES model was developed to determine the best BES model under a free-floating regime. The combination of the number of layers [double (D) and single (S)], geometry mode [3D and manual (M)], and layer type [massless (M) and no glazing window (W)], led to the development of five models: D_3D_M, D_3D_W, D_M_M, S_3D_W, and S_M_M. The simulation was performed in a standard radiation mode, and the output parameters were temperature and relative humidity (RH). R2 and the root square mean error (RSME) were used to check the fitness and degree of deviation, respectively, to validate the models. Analysis of variance (ANOVA) was employed to investigate the significant differences among the models, whereas contour plots were used to compare the distribution pattern between the significant models and experimental data. Validation of the models showed that the obtained R2 values ranged from 0.86 to 0.95, and the RSME values for the temperature were between 2.64°C and 3.91°C. These values were 0.91-0.93 and 19.72%-30.32% for RH. The ANOVA (P<0.05) result exhibited significant differences between the S-scenario models and experimental central points in temperature and RH. However, the D- and S-layer scenarios with a 3D geometry and massless layer showed similar distributions with their corresponding experimental greenhouses. Hence, 3D_M was regarded as the best combination in the discretised BES model.Item EFFECT OF GLAZING CONFIGURATION AS AN ENERGY-SAVING STRATEGY IN NATURALLY VENTILATED GREENHOUSES FOR STRAWBERRY(Journal of Agricultural Engineering, 2021-05-10) Akpenpuun, TimothyStrawberry cultivation is highly dependent on environmental parameters and energy in winter. Two gothic greenhouses with different glazing material combinations, i.e. polyolefin-thermal screen (PoTS) and polyolefin-thermal screen-polyethylene (PoTSPe), were used for strawberry cultivation. The energy-saving capabilities of the two configurations and their impact on the microclimates of the greenhouses were investigated. Temperature, relative humidity, vapor pressure deficit, leaf temperature, and solar radiation over the experimental period in the PoTS greenhouse were 13.0±2.3°C, 75.8±6.5%, 0.4±0.1 kPa, 13.6±1.7°C, and 168.8±82.3W/m2, respectively, whereas in the PoTSPe setup they were 13.1±2.3°C, 80.0±5.7%, 0.3±0.1 kPa, 13.5±1.6°C, and 183.1±90.5 W/m2. The mean fuel consumption by the PoTS and PoTSPe greenhouses were 5.5 and 3.5 L, respectively. The performance analysis shows that both greenhouses were able to maintain the environmental parameters and leaf temperature within the recommended ranges, although more energy was consumed with PoTS. A higher yield was obtained in the PoTS greenhouse, which, however, was not significantly different from the PoTSPe yieldItem Effect of glazing configuration as an energy-saving strategy in naturally ventilated greenhouses for strawberry (Seolhyang sp.) cultivation(Journal of Agricultural Engineering, 2021-04-24) Akpenpuun, TimothyStrawberry cultivation is highly dependent on environmental parameters and energy in winter. Two gothic greenhouses with different glazing material combinations, i.e. polyolefin-thermal screen (PoTS) and polyolefin-thermal screen-polyethylene (PoTSPe), were used for strawberry cultivation. The energy-saving capabilities of the two configurations and their impact on the microclimates of the greenhouses were investigated. Temperature, relative humidity, vapor pressure deficit, leaf temperature, and solar radiation over the experimental period in the PoTS greenhouse were 13.0±2.3°C, 75.8±6.5%, 0.4±0.1 kPa, 13.6±1.7°C, and 168.8±82.3W/m2, respectively, whereas in the PoTSPe setup they were 13.1±2.3°C, 80.0±5.7%, 0.3±0.1 kPa, 13.5±1.6°C, and 183.1±90.5 W/m2. The mean fuel consumption by the PoTS and PoTSPe greenhouses were 5.5 and 3.5 L, respectively. The performance analysis shows that both greenhouses were able to maintain the environmental parameters and leaf temperature within the recommended ranges, although more energy was consumed with PoTS. A higher yield was obtained in the PoTS greenhouse, which, however, was not significantly different from the PoTSPe yield.
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