Search

A water resource recovery facility sited in a region at a high elevation has experienced the effects of over‐designing its blowers. In this case study, we used off‐gas analysis and site‐specific power tariffs to quantify actual process loading and air requirements, and we quantitatively evaluated various options for blower replacement or upgrade. Off‐gas analysis mapped the oxygen uptake rate at the surface of the tank, suggesting that the tanks were not evenly loaded across their sections. The local cost of energy directly affects the return on the investment calculation and limits the available solutions. The payback of partial or complete blower replacement may not be justified even in the event of excessive aeration, and the sequencing of aeration system improvements including diffuser replacement, process controls, and blower modifications should be evaluated contemporaneously. Practitioner Points: Off‐gas analysis can be used to evaluate process loading imbalances by mapping the oxygen uptake rate.Alpha factors from off‐gas testing are used in process models to evaluate air requirements and blower air demand.Comparative evaluation of blowers must be done considering the net present value of the status quo, upgrades, or replacement. [ABSTRACT FROM AUTHOR]

Blowers are widely used in tasks such as ventilation, exhaust, drying, cooling, heat dissipation, or conveying medium, and they usually consume a lot of energy. There is an inevitable gap between the rotating impeller and static volute casing due to manufacturing tolerance and thermal deformation. The circulating flow in the gap has an important effect on the performance of the blower. In this study, computational fluid dynamics (CFD) was used to investigate the performance of the blower under different flow conditions and gaps, and the accuracy of the numerical simulation was verified by performance experiments. The results show that the flow separation under low flow conditions in the impeller channel can be suppressed by the circulating flow. However, the efficiency of the blower is decreased because a part of the power is used to maintain the circulating flow. Under design conditions, efficiency is reduced by 5.3~8.2%, depending on the gap sizes. Due to the increased flow rate in the impeller channel caused by the gap circulating flow, the net flow rate of the impeller under design conditions is about 12% higher than the inlet flow rate of the blower. Therefore, it leads to an increase of about 12% in impeller efficiency calculated by the net flow rate compared with the inlet flow rate. Finally, the flow field distribution on the impeller channel under different gap conditions was compared, and the effects of the gap on the blower performance were analyzed from the perspective of flow field structure. [ABSTRACT FROM AUTHOR]

Battery electric vehicle (BEV) air conditioning systems often use positive temperature coefficient (PTC) heaters to heat the passenger compartment. The heating process consumes a lot of energy in low-temperature environments, which seriously affects the driving range and user experience. This study aims to reduce the low-temperature energy consumption of the air conditioning system and improve energy efficiency through an innovative optimization method. In this study, the energy consumption composition of the air conditioning system was analyzed, and the goal of minimizing the sum of the total power consumption of the PTC heater and the blower was determined, while the efficiency characteristic of the blower was considered at the same time. The relationship between the average temperature of the passenger compartment measurement points and the PTC power and airflow rate was studied by combining experiments and numerical simulations, and the alternative operating conditions that met the temperature requirement were determined. On this basis, the total power consumption of the air conditioning system was analyzed and optimized. The results show that PTC power, airflow rate, and blower efficiency all have an important influence on the total power consumption of the air conditioning system. The optimized scheme could reduce the theoretical total power from 1315.32 W of the original scheme to 1246.83 W, and the actual total power from 1350.05 W of the original scheme to 1326.56 W, with reductions of 5.21% and 1.74%, respectively. The low-temperature energy consumption optimization method for the BEV air conditioning systems proposed in this study is instructive for the selection of blowers and the design of control strategies for air conditioning systems. [ABSTRACT FROM AUTHOR]

In this research paper, three different arrangements of Solar Air Heaters (SAH) have been modeled and experimentally analyzed. The first solar heater is the Simple Solar Air Heater with tin cans, second has added reflecting mirrors with tin cans and third has a triangular fins arrangement on a copper plate. The outlet temperature of the air, solar heater efficiency, pressure drop, exergy, and exergy destruction have been determined for three arrangements of solar air heaters and compared with each other. The best performer SAH among the three was finally validated with the previous study on evacuated tube pipe solar air heater. After experimental and modeling results, it is concluded that the performance of evacuated tube pipe solar heater is better than tin cans reflecting mirror solar air heater in morning and evening and at noon the performance of reflecting mirror solar air heater is better since the addition of reflecting mirrors increase the heat supplied on the tin can tube in the afternoon time. [ABSTRACT FROM AUTHOR]

This paper presents a new 4-lobe blower for supercharging a two-stroke engine. Based on a modified Roots compressor manufactured prototype shows pros and cons of an innovative profile. The results demonstrate that the shape of rotor edges effect out pressure stability. The measurement results include the main assessed parameters: outlet pressure, overall efficiency, losses and outlet air temperature.

The COVID-19 pandemic has revealed numerous global health system deficits, even in developed countries. The high cost and shortage of treatment, health care, and medical devices are the reasons. Aside from new mutations, the availability of respirators is an urgent concern, especially in developing countries. Even after the pandemic, respiratory diseases are among the most prevalent diseases. Researchers can help reduce treatment costs by offering scalable, open-source solutions that are manufacturable. Since March 2020, serious efforts have been made to reduce the problems caused by the lack of respirators at the lowest possible cost. In this research paper, a unique and integrated solution for a fully automatic ventilator is presented and described. The design considers the cost, speed of assembly, safety, ease of use, robustness, portability issues, and scalability to fit all requirements for emergency ventilation. Furthermore, the device was developed using turbine technology to generate air pressure. The work describes a low-cost alternative ventilator that uses a novel proportional-valve approach to control oxygen mixing process, control circuit, and control algorithm. The current software supports pressure mode controllers, and it can be upgraded to volume-mode or dual mode without any modifications in the hardware. In addition, the hardware, particularly the electronic circuit, has idle input/output ports for further development. Based on the evaluations of the developed ventilator using an artificial lung, the system exhibited acceptable accuracy regarding to the pressure, leak compensation, and oxygen concentration levels. The designated safety conditions have been met, and the safety alarms tripped according to any violations. Moreover, all design files are provided with clear instructions to rebuild the device, despite the complexity of electronics assembly. The system can be described as a development kit, which can shorten the time for researchers/manufacturers to develop a device equivalent to the expensive devices available in the market. [ABSTRACT FROM AUTHOR]

Copyright of Archeologia Technica is the property of Technical Museum in Brno and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Regenerative flow machines are known to be simple in construction but complex in flow characteristics. Due to this reason, the design of these machines has been primarily esoteric, and hence its performance heavily relies on the experience and expertise of the designer. Since there are no established rules of thumb for designing them, this paper attempts to provide simple design correlations for systematically designing regenerative flow machines viz. pumps, blowers, and compressors. Three different impeller designs have been considered, namely the (i) single-side vane impeller, (ii) double-side vane impeller, and (iii) peripheral vane impeller, for the three types of machines. More than ten design parameters have been considered for sizing the machines. Experimental and computational data available in open literature have been used to obtain physically meaningful correlations in simple form, and require minimal and practically available inputs. Fluid properties and practical constraints were taken into consideration while deriving the correlations. Constants in the correlations were obtained using least square regression analysis. The accuracy of the obtained correlation is determined by the correlation coefficient. The deviation obtained using the derived correlations varied from 10 to 25%. A consolidated set of correlations has been presented, which will be helpful in making a preliminary design before CFD simulation, design optimization, and prototype building. Finally, the obtained correlations have been used to demonstrate the design of a regenerative flow pump. [ABSTRACT FROM AUTHOR]

The efforts to increase capacity while maintaining the granulation of the grinding process are carried out to maximize the use of the hammer mill machine, which is the second largest electric energy consumption in a plant. The method that can be done to achieve this is by setting the screen position and setting the right blower opening. Standard screen specifications will maximize the capacity of the grinding process and produce optimum granulation. In order to get the maximum grinding capacity, DFCO can be set at the maximum but will have an effect on the motor current during the grinding process, the average current will tend to be high.The aim of this research was to determine the effect of variations in the screen’s and blower’s position settings on the capacity and granulation of raw materials from the grinding process. The usage of 2.5 mm and 3 mm diameters screens, as well as adjusting the screen position of 2.5 mm at the top and 3 mm at the bottom, resulted in better capacity and granulation than using a screen with only 3 mm diameter. The larger the blower and DFCO openings, the greater the grinding capacity, but also increased the motor current. The larger the blower opening, the greater the decrease in the water content of grinding raw materials.

Renewable energy source is insisted in all areas of technology, especially the adaptation of solar power for various purposes. The present investigational study is carried out to improve the efficiency of PV/T solar still using enhanced evaporation and condensation technique. A DC-powered blower is fixed inside single slope solar still which increases the turbulence of evaporated vapor from the saline water inside the solar still while the condensation is improved using the cover cooling technique. The experiment is conducted on a constant water depth of 1 cm with three different blow rate periods (5 min, 10 min, and 15 min). The blower runs and stops for 30 seconds time period in all blow rates. To improve the efficiency of the photovoltaic system, an inorganic phase change material (PCM) (Glauber salt (Na2SO4.10H2O) is used underneath the PV panel for cooling the panel. To obtain a higher production rate of distilled water, a nickel-chromium (NiCr) heater is placed in the solar still which is powered by the integrated solar PV system. This proposed work helps to enhance the freshwater production process from saline water and also solar power production. From this investigation, it is observed that the proposed PV/T solar still gives an improved overall thermal and electrical efficiency of almost 12.5% and 11.5% respectively, and is superior as compared to the conventional solar still. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Soil Sciences & Agricultural Engineering is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the present study, the authors investigate the simplest model of cross-flow impellers, in order to provide the fundamental flow features of cross-flow impellers. The model is a two-dimensional cross-flow impeller with a very-high aspect ratio, and rotates in stationary fluid. More strictly, we occasionally place a splitter plate with minimal influence instead of casings for more precise observations and measurements. Instantaneous measurements of flow-velocity vectors on the mid-span plane are conducted using a CCD camera and a double-pulse YAG laser with a particle-image-velocimetry technique, in addition to conventional flow visualisations and hot-wire-velocimetry measurements. As a result, the authors show the revolutional motion of such an eccentric vortex as a large-scale re-circulating flow structure inside the cross-flow impeller, and reveal the detail of flow features at Reynolds number Re = 300-2500. Furthermore, the authors show the relations between Re and out-flow rate from the impeller.

Wastewater treatment plants operate with water flows and characteristics different from those considered in the design stage, the most common differences being found in carbon concentrations that are lower than those of the design, nitrogen concentrations higher than those considered and a disadvantageous C:N:P ratio. This fact means that, during the entire period of operation, decisions are needed leading to wastewater treatment process optimization. The present paper deals with methods of regulating for a nitrification and simultaneous denitrification biological reactor, based on the determinations made for nitrogen concentrations, dissolved oxygen, pH, blowing speed and results obtained related to the treatment efficiency. The analysis proves that the necessary wastewater treatment efficiency is obtained by balancing the nitrification and denitrification processes accompanied by the reduction of energy consumption through recovering oxygen from nitrates, which can be controlled by blowing speed and detecting the operation mode between sequential or continuous ones. Interpretations and conclusions can support operators in finding solutions to optimize the undertaken process. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Soil Sciences & Agricultural Engineering is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Currently, total electricity consumption of furnaces is unregulated, tested at laboratory conditions using the DOE test procedure, and is reported in the GAMA directory as varying from 76 kWh/year to 1,953 kWh/year. Furnace blowers account for about 80percent of the total furnace electricity consumption and are primarily used to distribute warm air throughout the home during furnace operation as well as distribute cold air during air conditioning operation. Yet the furnace test procedure does not provide a means to calculate the electricity consumption during cooling operation or standby, which account for a large fraction of the total electricity consumption. Furthermore, blower electricity consumption is strongly affected by static pressure. Field data shows that static pressure in the house distribution ducts varies widely and that the static pressure used in the test procedure as well as the calculated fan power is not representative of actual field installations. Therefore, accurate determination of the blower electricity consumption is important to address electricity consumption of furnaces and air conditioners. This paper compares the potential regional and national energy savings of two-stage brushless permanent magnet (BPM) blower motors (the blower design option with the most potential savings that is currently available in the market) to single-stage permanent split capacitor (PSC) blower motors (the most common blower design option). Computer models were used to generate the heating and cooling loads for typical homes in 16 different climates which represent houses throughout the United States. The results show that the potential savings of using BPM motors vary by region and house characteristics, and are very strongly tied to improving house distribution ducts. Savings decrease dramatically with increased duct pressure. Cold climate locations will see savings even in the high static pressure duct situations, while warm climate locations will see less savings overall and negative savings in the high static pressure duct situations. Moderate climate locations will see little or no savings.

A motorized rice de-stoning machine was locally developed for separating stone pebbles from milled rice. Major component being the reciprocating screen coupled with the blower and the hopper. The stone separation is achieved by vertical oscillation of the reciprocating screen coupled with a suction - like air produced by the blower directly beneath the screen causing rice - mixture to float just above the screen and the stones are sucked up the reciprocating screen then discharged through the stone chute and the clean rice collected in opposite order. The de-stoning machine was designed to be powered by a high speed (2980 r min-1) 0.746 kW electric motor. It was evaluated for its efficiencies in terms of rice separation and de-stoning, the tray loss and impurity level after separation were also evaluated. The highest de-stoning efficiency was recorded between 5 to 7 mm feed gates as 99.75% and the lowest was recorded at a feed gate of 20 mm as 82.5%. The highest rice separation efficiency was recorded at 5 mm feed gate to be 98.89% and the lowest of 93.33% was at 20 mm. The highest values of impurity level and tray loss were recorded at 20 mm as 2.041% and 6.67% respectively, while the lowest values were recorded at 5 mm as 0.028% and 1.11% respectively. The capacity also increased as the feed gate increase. All results showed a high correlation with feed gate. [ABSTRACT FROM AUTHOR]

In this research, the pneumatic conveying characteristics of soya bean (Glycine max L.) of Atakisi variety were determined. The length, width, thickness, arithmetic mean diameter, geometric mean diameter, sphericity, volume, thousand seed mass, bulk density, true density, porosity, projected area, terminal velocity, drag coefficient, pressure drop, power consumption, and seed damage, namely mechanical damage, germination test, and seed vigour index were investigated experimentally. The positive low pressure system was used for conveying of soya bean. The power requirement and pressure drop increased with increase in revolution of blower and conveying capacity decreased with increase in pipe diameter. The highest pressure drop and power requirement were obtained for 54.5 mm pipe diameter, while the lowest pressure drop was found for 70.3 mm pipe diameter. The mechanical damage to the soya bean for both pipe diameter increased as the revolution of blower increased. [ABSTRACT FROM AUTHOR]

The production of biofuels and biochemicals from biomass-based feedstock, which is one of the most promising strategies for replacing petroleum-based resources and thus alleviating global warming, has received increasing attention in recent years. However, this strategy is energy-intensive due to the low product concentrations after transformation step. In this study, a novel hybrid-blower-and-evaporator-assisted distillation configuration (HBED) was proposed for enhancing process efficiency in bioproduct production from biomass. Several important industrial cases have been investigated to demonstrate the proposed configuration. By applying HBED, light components are partially removed in an evaporator, and the latent heat can be circulated during the process, leading to a substantial improvement in energy efficiency. A blower can increase the energy efficiency of an evaporator significantly, while the combination of an evaporator and blower can substantially reduce the size, capital cost, and operating cost of the distillation column. The results show that the proposed HBED configuration can achieve significant energy savings. Notably, the operating costs can be reduced by up to 45.4%, 26.3%, and 36.7% for the levulinic acid, 2,3-butanediol, and furfural purification processes, respectively. Furthermore, the CO 2 emissions of a conventional column and the proposed configuration are evaluated and compared. [ABSTRACT FROM AUTHOR]

Comparing with the common air cycle heat pumps using electrical machine as the prime mover, an air cycle heat pump with a turbocharger driven by a blower (ACHPTDB) could not only cuts down the initial cost, but also reach a balance between the heating capacity and heating load. The blower is chosen as the prime mover and the turbocharger takes place of the compressor and expansion valve/expander. A thermodynamic model for the ACHPTDB was built by using finite-time thermodynamics (FTT). The performance of the model was optimized associated with the air mass flow rate and subsequent distribution of pressure drops, which indicates the thermodynamic performance can reach its maximum by adjusting the air mass flow rate. It is also shown that heating COP has a maximum with respect to the blower pressure ratio or other parameters, which indicates there exists a tradeoff in how the mass flow rate and the blower pressure ratio should be allocated to make heating COP reach its optimization. [ABSTRACT FROM AUTHOR]

This research optimizes a heatsink fin wave that improves the cooling and heating efficiency in a Climate control seat (CCS). The design of existing CCS considers the occupant's pressure, duct shape, blower blade shape, blower cogging torque, and mesh nozzles. However, the heatsink fin wave shape is overlooked in spite of its outstanding thermal efficiency. To address such problems, this research optimized the shape of the heatsink by defining the wave pitch, height pitch, and fin pitch. Parametric analysis (PA) was used such that the effective decision of the variables could be selected within each range of the variances. As a result, the cooling and the heating system operated more efficiently and the time required to reach the target temperature was reduced when compared to the existing system. The performance of the CCS was demonstrated by simulations and experiments. [ABSTRACT FROM AUTHOR]

The multi-blade fan, which has been widely used as a blower for air-conditioning systems of vehicles, is one of the well-established fluid machinery. However, many factors must be considered in its practical design because the flow generated in the fan is quite complicated with three-dimensionality and unsteadiness. The fundamental fan performance is primarily determined by the impeller of the fan, and is also affected by the scroll casing. However, the theoretical estimation of the effect of the casing on the performance has not been well established. In order to estimate the casing effect on fan performance, detailed three-dimensional (3D) flow analysis in the casing is necessary. Stereoscopic PIV (SPIV) is one of the useful techniques for experimental analysis of 3D flow fields. There are some difficulties in practical application of SPIV for flow analysis in fluid machinery with complicated geometry, but the results obtained provide useful information for understanding the 3D flow field. In this report, experimental investigation of the flow in the scroll casing has been carried out using PIV and SPIV under the premise of downsizing automobile air conditioner fans.

Time frequency analysis of the surge onset was performed in the centrifugal blower. A pressure signal was registered at the blower inlet, outlet and three locations at the impeller shroud. The time-frequency scalograms were obtained by means of the Continuous Wavelet Transform (CWT). The blower was found to successively operate in four different conditions: stable working condition, inlet recirculation, transient phase and deep surge. Scalograms revealed different spectral structures of aforementioned phases and suggest possible ways of detecting the surge predecessors.

In this paper, we present a study on a jet flow, assisted by low net charge ion wind from bipolar corona discharge setup. The ion wind is simultaneously generated from both positive and negative electrodes placed in parallel, adding momentum to the bulk flow directed alongside the electrodes and focused in the middle of interelectrode space. The electrodes are connected to a single battery-operated power source in a symmetrical arrangement, where the electrode creating charged ions of one polarity also serves as the reference electrode to establish the electric field required for ion creation by the opposite electrode, and vice versa. Multiphysics numerical simulation is carried out with programmable open source OpenFOAM, where the measured current-voltage is applied as a boundary condition to simulate the electrohydrodynamics flow. The jet flow inside the device is verified by hotwire anemometry using hotwires embedded within the device, with the measured values in good agreement with simulation. The corona discharge helped to focus the jet and increased the flow peak velocity from 1.41 m/s to 2.42 m/s with only 27.1 mW of consumed discharge power. The device is robust, ready-to-use and minimal in cost. In addition, as the oppositely charged corona flows are self-neutralized, the generated air flow remains neutral and therefore does not attach to a particular target, which expands the application range. These are important features, which can contribute to the development of multi-axis fluidic inertial sensors, fluidic amplifiers, micro blowers, gas mixing, coupling and analysis with space constraints and/or where neutralized discharge process is required, such as circulatory flow heat transfer or the formation of low charged aerosol for inhalation and charged particle deposition. [ABSTRACT FROM AUTHOR]

Solar distillation is one of the important methods for water purification. This paper examines the performance of solar distillation system at different air flow rate. To increase the performance of distiller, artificial wind was created by fan and suitable wind speed was investigated to increase the amount of water distilled. The experiments were carried out in Elazığ climate conditions. In order to examine the effect of the wind speed on solar distillation system, two stills were manufactured with the size of 1000x1000 mm. One of them was the conventional still which was used as a reference. The other still was used to investigate experimentally the effect of the wind speed. Graphs were drawn for time-dependent changes in the amount of water distilled. It was found that that the productivity of the fan-still distiller was 14.7 % greater than that of a conventional still. [ABSTRACT FROM AUTHOR]

Different techniques and tools have been introduced for the analysis of process systems that each has their own capabilities namely HAZOP. HAZOP analysis is a process hazard analysis method that has been widely applied both within and outside the chemical processing industries. One of the process systems which require to be analyzed by these techniques is the sulfur recovery unit (SRU) of the gas processing plants. This paper presents the HAZOP analysis method which is employed to identify all the dangerous deviations, potential hazard, and operational problems possibly existing in the Claus reaction furnace package, blower, and heat exchanger equipments in the SRU. This allows a significant reduction in implementation costs, where the expected saving from risk reduction is high. The efficiency of SRU is strongly associated with the performance of those aforementioned equipments. However, it is important to point out that these equipments are the most important parts of the SRU. Useful recommendation is presented to reduce risk ranking. Finally, Cause and effect diagrams for Claus Burner in Start-up/Heating and Fuel Gas + Sour Gas Modes have been designed. The novelty of the submitted paper as compared to the state of the art in the literature can be summarized below. For the first time the HAZOP study was considered to be implemented to cover both hazard and operability analysis of the sulfur recovery units main equipment such as Claus reaction furnace package, blower, and heat exchanger of South Pars gas processing plant. According to the less systematical attempts for preventing dangerous accidents in the SRU equipment we have used HAZOP study as a method of systematically identifying every conceivable process deviation, abnormal causes and adverse hazardous consequences in the SRU. [ABSTRACT FROM AUTHOR]

Highlights: [•] A quasi-dynamic method is proposed for examination of centrifugal blower. [•] Results are presented in a form of the spectral maps. [•] Maps allow to establish moment of occurrence and frequency of flow phenomena. [•] Surge is preceded by high pressure jumps within inlet zone. [•] Surge frequency is in agreement with the Helmholtz formula approximation. [Copyright &y& Elsevier]