Fan Speed Research Articles

Internet of Things Enabled Smart Animal Farm Prototype

Livestock plays very important economic, social and cultural roles in the well being of rural communities across the world. Quality environmental conditions, automation and monitoring are the key necessities of running a good and profitable livestock farm. Air quality, temperature of the surroundings and humidity play a major role while deciding the fan speeds of the exhaust System used in all aspects of livestock farming. Another important part of livestock production is increasing incubation speeds of eggs by performing artificial incubation. It is a requirement to maintain the temperature at a constant value in this system. This paper describes two mutually exclusive Fuzzy Logic algorithm-based systems to automate the exhaust system and an artificial egg incubator. The other important part of a livestock farm is production of milk and milk products. It is required to monitor the health of cows by overseeing their activities at any point of time. This can be done by determining and monitoring the activities performed by the cow. This paper describes a simple Deep Learning Model to classify the activities of a cow broadly as standing, walking or grazing. The Exhaust and the Incubator system are controlled and monitored using Internet of Things (IOT) System using a native web application developed using the Flask framework.

Predictive optimization of the air flow rate for a residential heat pump in seasonal performance conditions

The seasonal performance has become increasingly important for residential heat pumps which occupy a majority of household power consumption. Thus, the heat pump system and its components are requested to be re-designed with reflecting the part load characteristics. Furthermore, actuators should be optimally operated for each test condition to maximize system efficiency. Among them, indoor and outdoor fan speeds are the only variable that can be independently controlled and have the widest operation range. Therefore, in this study, a non-iterative heat pump simulation model is presented to precisely predict the optimum air flow rate for each part load condition by introducing the modified effectiveness. The non-dimensional correlation is developed for the modified effectiveness and semi-empirical efficiency models are utilized for estimating the compressor performance. Validating experiments identify that the model can predict the optimum air flow rate for various part load conditions within an error of 10%. Consequently, the optimum air flow rate can be instantly obtained for various operating conditions.

Simulation to Determine The Amount of Fan Rotation on a Cooling Machine Using The Fuzzy Logic Method

This Fan Rotation Simulation Application on Cooling Machines with Fuzzy Logic is an application that can simulate the fan rotation process based on the input voltage and temperature given by the user. In carrying out this simulation, this application uses a stress index with a category of small, medium, medium, high or higher. Temperature index with categories cooler, cooler, warmer, warmer and hotter. While the fan speed index uses the very slow, slow, rather fast, fast and very fast categories. This system can analyze the amount of fan rotation in RPM (Rotation Per Minute) automatically based on the input voltage and temperature and is equipped with a graphic facility that displays the simulation results of fan rotation, namely temperature graphs and fan rotation graphs. However. The designed system is equipped with fan rotation speed animation, to simulate fan rotation in the temperature range of -50 C.

Comparison of Techniques for the Estimation of Flow Parameters of Fan Inflow Turbulence from Noisy Hot-Wire Data

Turbulence parameters, in particular integral length scale (ILS) and turbulence intensity (Tu), are key input parameters for various applications in aerodynamics and aeroacoustics. The estimation of these parameters is typically performed using data obtained via hot-wire measurements. On the one hand, hot-wire measurements are affected by external disturbances resulting in increased measurement noise. On the other hand, commonly applied turbulence parameter estimators lack in robustness. If not addressed correctly, both issues may impede the accuracy of the turbulence parameter estimation. In this article, a procedure consisting of several signal processing steps is presented to filter non-turbulence related disturbances from the unsteady velocity data. The signal processing techniques comprise time- and frequency-domain approaches. For the turbulence parameter estimation, two different models of the turbulence spectra—the von Kármán model and the Bullen model—are fitted to match the spectrum of the measured data. The results of several parameter estimation techniques are compared. Computational Fluid Dynamics (CFD) data are used to validate the estimation techniques and also to assess the influence of the variation in window size on the estimated parameters. Additionally, hot-wire data from a high-speed fan rig are analyzed. ILS and Tu are assessed at several radial positions for two fan speeds. It is found that most techniques yield similar values for ILS and Tu. The comparison of the fitted spectra with the spectra of the measured data shows a good agreement in most cases provided that a sufficiently fine frequency resolution is applied. The ratio of ILS and Tu of the velocity components in longitudinal and transverse direction allows the assessment of flow-isotropy. Results indicate that the turbulence is anisotropic for the investigated flow fields.

Transient Response of Ventilated Room Enclosure Subjected to Solar Radiation Load

The effect of incident solar radiation ray’s penetration through glassed windows of duct - ventilated room enclosure air is investigated assuming constant solar intensity. The room is supplied with cold dry air through rectangular duct and the air is distributed through two grid ceiling fans located at the duct exit. The effect of fixed solar intensity penetration with variable fans rotational speed at specified time intervals is investigated upon the room temperature distribution and is simulated using the ANSYS CFX package. The results showed the variation in room temperature distribution at a specified time period (1, 2, 3 minutes) with increased fan speed becomes more efficient, also the transient room temperature distribution response to the solar radiation is significantly present in the simulation noticing fans effect on accelerating heat transfer rate through the domain.

Mining Fuzzy Temporal Gradual Emerging Patterns

Gradual emerging patterns (GEPs) are gradual item sets that occur less frequently in one data set and more frequently in another. For instance, let ‘fan speed’ and ‘temperature’ be attributes of two numerical data sets. A gradual item set “the higher the speed, the lower the temperature” (which correlates a data set’s attributes) becomes a GEP if it is less frequent (in terms of support as in frequent pattern mining) in one data set and more frequent in another. However, such patterns do not indicate how time gap impacts the emergence. Many correlations appear over time, for instance when phenomena appear after some meteorological situation due to latency. Previous works have not taken this temporal aspect into account. In this paper, we introduce temporal gradual emerging patterns (TGEPs) which are temporal gradual patterns (TGPs) whose frequency supports increase significantly between transformed data sets. For instance, a TGP “the higher the speed, the lower the temperature, almost 3 minutes later” becomes a TGEP if it occurs more frequently in one transformed data set than in another. Furthermore, we extend border manipulation to the case of mining TGEPs. In addition, we propose a more efficient ant colony optimization technique that exploits a heuristic approach to construct TGEPs.

A modified acoustic-turbulent scattering model for long-range propagation with wind tunnel validation

We present a newly developed ‘bridging’ model to quantify turbulent effects on long-range acoustic propagation in the atmosphere. The bridging model is incorporated into an existing validated Burgers’ equation solver. The new model combines the scattering model of Ostashev and Wilson and a traditional refraction model for acoustic-turbulent interaction. A new attenuation coefficient is obtained that is consistent with the atmospheric attenuation coefficient via integration of energy loss over all scattering angles. To validate and quantify the effect of the new model, we conduct a series of propagation experiments in the National Science Foundation funded University of Florida Boundary Layer Wind Tunnel. A synthetic noise signal propagates through the tunnel, which has controllable boundary layer turbulent statistics via fan speeds and hundreds of individually controlled roughness elements. We compare predictions of the bridging model, Ostashev and Wilson’s model, and the experiments of the wind tunnel. Also, we perform example long-range predictions using the new model and Ostashev and Wilson’s model with a synthetic tornadic infrasound signal. A sensitivity test of model parameters is performed. We show that for particular atmospheric conditions and turbulent statistics, the bridging model has particular advantages with minimal additional computational expense.

Dynamic-thermal and localized filament-kinetic attacks on fused filament fabrication based 3D printing process

3D printing materializes physical objects through sequentially depositing thin layers. The layer-by-layer stacking involves controlling 3D printing parameters (e.g., fan speed, nozzle temperature, printing bed temperature, and filament extrusion rate) to ensure conformity to a CAD (Computer-aided Design) model. Attackers target the parameters during a printing process to sabotage the printing object. This paper presents four new sabotage attacks on the fused filament fabrication (FFF)-based 3D printing process: (1) cavity through filament-kinetics, (2) density variation through filament state, (3) density variation through filament speed, and (4) dynamic-thermal manipulation. These attacks produce an insignificant attack footprint on a finished printed object by targeting localized regions or using small changes in temperature profile, making them hard to detect. Specifically, the first three attacks manipulate filament-kinetics to change the print density or create a cavity in a small localized region, while the fourth attack makes slight changes to the nozzle temperature to manipulate thermal stress in a printing object without creating any visual deformation. Mechanical (tensile and three-point bending) tests carried out on the objects under attack demonstrate that these attacks with insignificant attack footprints can still change the physical properties (e.g., stress and strain) of the printed objects.

Thermal comfort analysis of a naturally ventilated regular size room equipped with ceiling fan

Residential and commercial buildings in India being the bigger contributors to energy consumption possess large energy-saving potential. There is a significant increase in the use of air conditioning to achieve thermal comfort, thereby increasing the total energy consumption and related CO2 emissions. Ceiling fans are common in almost every habitable space of Indian residences, can be used as a hybrid ventilation system. A ceiling fan having exceptionally low energy consumption can be used to achieve thermal comfort thereby limiting the use of air conditioners. In this study, thermal comfort analysis was carried out on a naturally ventilated regular size room equipped with ceiling fan. The room is 3.96m x 3.96m x 3.05m in size. Ceiling fan inside the room generates the air flow and thermal fields. 166 rpm, 215 rpm and 250 rpm are the three fan speeds selected for this study. Both Computational Fluid Dynamics (CFD) simulation and experimental analysis was conducted. By analysing both numerical and experimental results, 215 rpm fan speed is selected as an optimum speed to achieve thermal comfort in regular size room. This proves fan can be used as a stand-alone device to achieve thermal comfort, where the indoor temperature is maintained at 28°C.

Accelerating self-optimization control of refrigerant cycles with Bayesian optimization and adaptive moment estimation

This paper presents a model-free self-optimization control algorithm for modulating multiple inputs simultaneously to minimize the power consumption of a vapor compression system (VCS). We propose the use of Bayesian Optimization (BO) to warm-start a state-of-the-art extremum seeking control (ESC) algorithm and then accelerate the ESC on-line with Adam, a well-studied adaptive moment-based optimization method used to solve high-dimensional non-convex optimization problems such as training deep neural networks. BO initializes the ESC at conditions favorable for rapid convergence while concurrently learning a surrogate map of VCS power consumption as a function of the inputs. In addition, the warm-start increases the likelihood of attaining a global optimum for locally convex, but globally non-convex, objective functions by identifying regions where the global optimum most likely resides. The proposed algorithm is evaluated using a Modelica model of an air conditioning system with variable compressor speed, an electronic expansion valve and two variable speed fans. We demonstrate the acceleration of this algorithm in simulations of an occupied space with a realistic heat pump model with realistic ambient temperature profiles, variation in heat-load, and different actuation rates. We also show that, in spite of the presence of unknown exogenous disturbances, the proposed algorithm computes better set-points, faster than the ESC. We also observe that the proposed method improves transient performance compared to the state-of-the-art. • Learn calibration cost functions instead of dynamical models for setpoint optimization. • Energy model learned analytic model of underlying system dynamics. • Accelerate convergence of extremum-seeking algorithms via Bayesian optimization. • Optimize many setpoints at various operating modes without re-estimating gradient. • Case study with high-fidelity Modelica heat pump model in realistic environment.

Energy utilization assessment of a semi-closed greenhouse using data-driven model predictive control

With the global increase in food demand, closed and controlled greenhouses are an essential source for year-round crop production. Maintaining the optimum conditions inside the greenhouse throughout the year is critical to improving crop quality and yield. However, greenhouses consume more resources than other commercial buildings due to their inefficient operation and structure. Therefore, a data-driven model predictive control approach for a semi-closed greenhouse is proposed for temperature control and reducing energy consumption in this study. The proposed method consists of a multilayer perceptron model representing the greenhouse system integrated with an objective function and an optimization algorithm. The multilayer perceptron model is trained using historical data from the greenhouse with solar radiation, outside temperature, humidity difference, fan speed, HVAC control as the input parameters to predict the temperature. The greenhouse model's performance is evaluated under varying scenarios, such as increasing the prediction time step and changing the number of samples in the training data set. Results illustrated that the MPC approach had a better temperature control than the greenhouse adaptive control system for winter and summer with an RMSE value of 0.33 °C and 0.36 °C, respectively. Similarly, model predictive control resulted in an energy reduction of 7.70% for winter and 16.57% for the summer season. The proposed model predictive control framework is flexible and can be applied to other greenhouse systems by tuning the model on the new data set.

ОПТИМИЗАЦИЯ ПАРАМЕТРОВ ВЕНТИЛЯТОРНЫХ УСТАНОВОК АППАРАТОВ ВОЗДУШНОГО ОХЛАЖДЕНИЯ ГАЗА

Purpose of the study. Optimization of the parameters of high speed fan units of air coolers, the combination of which achieves the highest economic efficiency of fan units and, accordingly, the most rational range of specific speed values for the modes of maximum efficiency of fan units in combination with the relative diameter of the sleeve. Development of a mathematical model for determining the local values of the parameters of the efficiency of highspeed fan installations. Sustainable development of territories with active subsoil use is closely related to solving the problems of improving industrial safety and the efficiency of cooling the compressed gas at compressor stations of main gas pipelines, which actualizes the problem of mathematical modeling of energy conversion processes in the impellers of fan units of gas air coolers (AVO) to increase the competitiveness of the oil and gas complex RF in the context of globalization. Research methods. To optimize and determine the limiting combination of calculated parameters, the mathematical method of searching for the area of local maxima of a multiparameter problem in this part was performed in two stages: a mathematical model was built for determining the local values of the parameters that ensure the highest efficiency of fan installations with high speed; the most rational limiting combination of design parameters was determined, at which the highest economic efficiency of fan installations is achieved. Research results. The possibility of increasing the economic efficiency of axial fan units of high speed, made according to aerodynamic schemes with one impeller for gas air cooling devices, has been established. Using the mathematical analysis of the basic laws of axial turbomachines, equations for the efficiency of a fan unit and a fan are obtained, depending on the specific speed. Formulas are obtained for the maximum values of the efficiency of the fan and the fan unit of various specific speed depending on the coefficient of the consumpconsumption speed and on the relative diameter of the impeller sleeve. A method is proposed for constructing aerodynamic schemes of axial fan units for air-cooled gas coolers of the "K" type with maximum maximum values of efficiency for given values of specific speed, relative diameter of the impeller sleeve, aerodynamic quality of the impeller profiles, coefficient of aerodynamic resistance of the flow path of the coefficient of flow velocity. The possibility of creating a fan installation with a speed of ny ≥ 400 with an efficiency of at least ηy=0,86. Application area. Enterprises of the oil and gas complex of the Russian Federation for cooling compressed gas using AVO compressor stations of main gas pipelines.

Improvement of Temperature and Humidity Control of Proton Exchange Membrane Fuel Cells

Temperature and humidity are two important interconnected factors in the performance of PEMFCs (Proton Exchange Membrane Fuel Cells). The fuel and oxidant humidity and stack temperature in a fuel cell were analyzed in this study. There are many factors that affect the temperature and humidity of the stack. We adopt the fuzzy control method of multi-input and multi-output to control the temperature and humidity of the stack. A model including a driver, vehicle, transmission motor, air feeding, electrical network, stack, hydrogen supply and cooling system was established to study the fuel cell performance. A fuzzy controller is proven to be better in improving the output power of fuel cells. The three control objectives are the fan speed control for regulating temperature, the solenoid valve on/off control of the bubble humidifier for humidity variation and the speed of the pump for regulating temperature difference. In addition, the results from the PID controller stack model and the fuzzy controller stack model are compared in this research. The fuel cell bench test has been built to validate the effectiveness of the proposed fuzzy control. The maximum temperature of the stack can be reduced by 5 °C with the fuzzy control in this paper, so the fuel cell output voltage (power) increases by an average of approximately 5.8%.

Determination of the optimum operating parameters of an axial fan used on the conventional air blast orchard sprayer

The pesticide droplets are carried to the tree canopy with the assist of the air flow which is generated by an axial fan of orchard sprayer. The designers manufacture the fan of orchard sprayer with ability of 6 different working conditions under constant PTO speed. Previous studies were related to evaluating the effectiveness of sprayers. In this study, 6 different options that presented to farmers was evaluated with view of energy consumption and air flow. A Conventional orchard sprayer having an axial fan with 36” diameter was operated at two fan revolutions (1890 and 2430 rpm) and at three blade angles (15º, 30º, 45º), and measured air capacity, the fuel consumption, variations of air velocities in air jet profile of the fan and calculated power consumption for each operating parameters potentially to be chosen by farmers. As a result, for each blade angle, if the fan speed increase, the air jet of the fan become more uniform than before. The maximum fan efficiency and system efficiency were %73,25 and %59,98 respectively which were obtained 30o blade angle and 2430 rpm fan rotation speed condition. The minimum fuel consumption and torque need was obtained under conditions of 15o blade angle and 1890 rpm fan rotation speed. However, considering maximum air capacity and the best air velocity uniformity in the profile of fan jet was established at, 45o blade angle and 2430 rpm fan rotation speed operating parameters.

Comparative Analysis of Flow and Heat Transfer for Vehicular Independent Cooling Modules

To explore the internal flow distributions and heat transfer mechanism in different types of independent cooling modules for automotive, numerical, and experimental studies were conducted. According to the study, the independent cooling modules with parallel structure, on which the heat exchangers were located separately and close to the inlets, the performance improvement was significant. In addition, the opposite model in parallel structure was considered to be more efficient for it can obtain the same heat rejection at a lower fan speed, effectively reducing the fan power. Besides, the parallel structure in independent cooling modules offered the possibility to control the mass flow on each heat exchanger precisely with active grille shutter. This technology deserves more attention in terms of energy saving and emission reduction.

The Investigation of Savonius Type and Darrieus H Type Wind Turbine Simulation with Wind Speed Variable

The demand for electrical energy that continues to increase along with the advancement of civilization and also the increasing number of people as well as the reduced level of fulfillment and availability of non-renewable energy sources, it is necessary to have renewable energy resources that capable of fulfill these energy demand in a more environmental friendly. One of the natural energies that we can use is wind energy, which is easy to get and lasts continuously. This research examines the comparison of the power generated from the vertical axis wind turbine savonius type and darrieus H type. The wind that use in this research get from from the fan. The test is doing by varying the wind speed by adjusting the fan speed. The fan is directed to the wind turbine to rotate the wind turbine. To measure the wind speed produced by the fan, a digital anemometer is used. The result of this research is the relation data of voltage to rpm and voltage to wind speed of wind turbine.

축류팬 임계속도 예측에 대한 연구

The purpose of this study is to predict the critical speed of an axial fan using finite element analysis. The critical speed has an important meaning in evaluating the stability against the occurrence of overload of the ventilation system in an emergency situation of the axial fan. Through finite element analysis, the maximum stress acting on the axial fan was derived, and the results were derived for permanent deformation and fracture of the material by dividing it into an elastic region and a plastic region. The critical speed of the axial fan through the overspeed test and the analysis results of the finite element analysis were compared.

Increase of energy efficiency ratio of a direct evaporative cooler by dynamic behavior with energy and exergy analysis

The present research is about increasing the energy efficiency ratio (EER) in current direct evaporative coolers (DEC) in Iran. Increasing the cooling load and reducing the electrical energy consumption simultaneously (increasing the energy efficiency ratio (EER)) in DEC are the main goals of manufacturers and consumers of this device. When the circulation water pump runs continuously (static state), the circulation water rate is about 1.89 to 2.90 times of the amounts recommended in the reasonable standards. In order to adjust the circulation water rate to the recommended amount by standards, the present study has utilized repetitive cyclic scheduling programs to reduce the circulation rate to the optimal amount, (by turning the circulation pump on and off by dynamic pattern operation). In other words, the circulation pump stays on only for a certain period of a working cycle, and then the pump stays off for the rest of it. The cooling load and EER were measured based on ASHRAE 133 (2015). The results indicated that the cooling load in the dynamic state increased by 5.03 and 6.18 percent compared to the static state at low and high fan speeds, respectively. Moreover, in comparison with the static state, the amount of electrical energy consumed (kW-hr) in the dynamic state decreased by 8.8 and 4.2 percent at low and high fan speeds, respectively. Finally, the coefficient of performance (COP or EER) of the DEC in the dynamic state is increased by 15.16 and 10.78 in comparison with the static state at low and high fan speeds, respectively.

Optimization of the Process Parameters of an Air-Screen Cleaning System for Frozen Corn Based on the Response Surface Method

The threshing of frozen corn is accompanied by breakage and adherence, which influence the cleaning performance when the corn-cleaning mixture is separated and cleaned. In order to reduce the impurity ratio and loss ratio during frozen corn cleaning and provide theoretical support for frozen corn combine harvesting, this study employed a self-made air-screen cleaning system with adjustable parameters. The optimal process parameters of frozen corn cleaning were determined by using the response surface method (RSM). The influences of the fan speed (FS), vibrational frequency (VF), and screen opening (SO) on the cleaning performance were explored. The results showed that all three process parameters had significant effects on the impurity ratio (IR) and loss ratio (LR). The fan speed had the most significant impact. The cleaning performance was optimal when the fan speed was 102.7 rad/s, the vibration frequency was 6.42 Hz, and the screen opening was 21.9 mm, corresponding to a 0.80% impurity ratio and a 0.61% loss ratio. The predicted values of the regression models were consistent with the experimental results with a relative error of less than 5%. The reliability and accuracy of regression models were established and confirmed.

Dynamic modeling, validation and analysis of direct air-cooling condenser with integration to the coal-fired power plant for flexible operation

Coal-fired power plants with direct air-cooling condensers (DACC-CFPPs) have been widely used in areas rich in coal but short of water since they can significantly reduce water consumption. Despite its water-saving advantages, direct air-cooling condensers have inherent defects such as environmental and load sensitivity, higher costs and poor cooling performance, which deteriorate the economics and flexibility of the integrated system. For safe, efficient and flexible operation, this paper presents the development of a direct air-cooling condenser dynamic model integrated with a 600 MWe coal-fired power plant to study the interactions between heat and power within the entire DACC-CFPP under various load and ambient conditions. The condenser is modeled in a one-dimensional multi-section manner to reflect the impacts of crosswind and ambient temperature disturbances. A detailed turbine-feedwater heater system model is also developed to link the direct air-cooling condenser and power plant together. Steady-state and dynamic validations under various operating conditions are conducted, which demonstrate the high fidelity of the developed model. Simulation studies are then carried out to investigate the dynamic interactions between boiler-turbine, condenser and environmental conditions. We find that manipulating the fan array speed controls the condenser pressure effectively in terms of environmental disturbance rejection and load ramping. Motivated by this finding, a novel variable condenser pressure operating mode is proposed to coordinate the direct air-cooling condenser and coal-fired power plant operation, which can significantly improve the load tracking performance of the integrated plant.