Application of a Flow Optimizer in a Limited Space to Increase Series Fan Performance

2010 ◽  
Vol 7 (4) ◽  
pp. 181-188
Author(s):  
Jonathan Jilesen ◽  
Howard Harrison ◽  
Fue-Sang Lien ◽  
Darryl McCumber
Keyword(s):  
Power Consumption ◽  
Flow Rate ◽  
Operating Conditions ◽  
Cfd Analysis ◽  
Original Series ◽  
Fan Performance ◽  
Limited Space ◽  
Cooling Fans ◽  
Rate Of Cooling ◽  
Cooling Air

The performance increase of cooling for a 1U SunFire 4100 server through the introduction of multiple flow optimizers is investigated in this article. We found that the power consumption of cooling fans could be decreased by 17–33% depending on operating conditions. The use of flow optimizers was found to reduce noise produced by cooling fans by at least 5.3 dB(A). We also discuss the use of the increased performance to increase thermal head room by increasing the flow rate of cooling air by 6.5–20.4%. In addition, we found that a primary fan used with an exit stator allowed the overall fan module length to be reduced without a loss in performance. Reducing the length allowed the flow optimizers to fit into the standard 56-mm space previously occupied by the original series fans. CFD analysis was performed to better understand the effect of this stator on airflow.

scholarly journals Experimental and CFD analysis of rotary multi vane expander for small capacity generation

2018 ◽  
Vol 204 ◽  
pp. 06007
Author(s):  
Mohammad Mahardika
Keyword(s):  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Energy Demand ◽  
Energy Production ◽  
Energy Content ◽  
Operating Conditions ◽  
Volumetric Efficiency ◽  
Population Increase ◽  
Cfd Analysis

Every year, Indonesia's population increase so as energy demand. To fulfill Indonesia's energy needs, the capacity of energy production should be increased. Indonesia government has made a solution by propose 35.000 MW program to increase energy production and electrification ratio in Indonesia. An insulated area where electricity did not reach, has many problem to get electricity such as limited infrastructure, low fuel energy content, and expensive turbine. To solve these problem, multi-vane expander (MVE) can be used to extract the low energy and is cheap. MVE have many advantages such as cheap, easy to manufacture, able to operate with 2 phase, and able to low speed operation. But, the disadvantage of this type of expander is leakage. In this paper, experimental and CFD analysis of MVE are conducted. The experiment generated power of 25.7 watt with isentropic and volumetric efficiency of 11.6% and 11.7% by using operating condition of 1.5 bar, 115.6 °C, 626 rpm, and mass flow rate of 80 kg/h. The CFD model of the expander is created with the same dimension and operating conditions as experimental. The result for isentropic efficiency is inversely proportional with mass flow rate and for volumetric efficiency, power, and expander rotation are directly proportional with mass flow rate.

CFD Analyses of HPT Blade Air Delivery System With and Without Impellers

2011 ◽  
Author(s):  
Charles Wu ◽  
Boris Vaisman ◽  
Kevin McCusker
Keyword(s):  
Delivery System ◽  
Pressure Loss ◽  
Aerodynamic Performance ◽  
Operating Conditions ◽  
Manufacturing Cost ◽  
Cfd Analysis ◽  
Swirl Ratio ◽  
Blade Cooling ◽  
Supply Pressure ◽  
Cooling Air

In the design of a HPT blade cooling air delivery system, sufficient supply pressure is required to guarantee HPT blades are working properly in the high temperature environment. A design goal is to set a pressure level at the blade inlet that will prevent the ingestion of gaspath air into the blades which is caused by pressure fluctuations under various operating conditions and other uncertainties. Traditional 1-D design tools are not sophisticated enough for detailed system analysis. Therefore, CFD (Computational Fluid Dynamics) analysis was utilized for designing HPT blade cooling air delivery system to guarantee meeting the supply pressure requirement. Two HPT blade air delivery systems were explored. The baseline is a cooling air delivery system without radial impellers. It provides a simplistic design at low manufacturing cost, however CFD analysis shows that the system has a larger pressure loss at the broach slot entrance and delivers low supply pressure. The alternative is a cooling air delivery system with radial impellers. CFD analysis shows that the system with impellers results in much better aerodynamic performance at the broach slots and provides high supply pressure, but comes with the price of high manufacturing cost and lower TSFC due to the parasitic drag induced by impellers. For the alternative approach, three high solidity impeller designs were analyzed. The alternative approaches analyzed had inlet angles of 0°, 30°, 90° and exit angles of 0°, respectively. Comparisons of detailed aerodynamic performance are presented in the paper. CFD simulation reveals that the source of pressure loss without impellers is caused by mismatch of the swirl ratio at broach slot entrance. CFD results show that a system with radial impellers produces a better matched swirl ratio at broach slot entrance. Radial impellers enhance aerodynamic performance and improve pressure distribution within broach slots.

Parameter Study on Cooling System of Battery for HEV

2012 ◽  
Vol 538-541 ◽  
pp. 2038-2042
Author(s):  
Zhen Zhe Li ◽  
Yun De Shen ◽  
Gui Ying Shen ◽  
Mei Qin Li ◽  
Ming Ren
Keyword(s):  
Heat Flux ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Cooling System ◽  
Parameter Study ◽  
Analysis Model ◽  
Rate Of Cooling ◽  
Future Work ◽  
Cooling Air

A hybrid power composed of the fuel cell and MH-Ni battery has become a good strategy for HEV, but the performance of the battery cooling systems can not be easily adjusted. In this study, heat flux of the batteries and mass flow rate of cooling air have been investigated to improve the performance of a battery cooling system. As shown in the results, the error of root mean square has been decreased under the condition of decreasing heat flux of the batteries, and the performance of the battery cooling system has been improved with increasing the mass flow rate of cooling air. The analysis model developed in this study can be widly used to find out an optimal battery cooling system in the future work.

scholarly journals Modeling the Efficiency of External Gear Pumps Based on Similarity Considerations

2018 ◽  
Author(s):  
C. Schänzle ◽  
N. Störmer ◽  
P. F. Pelz
Keyword(s):  
Power Consumption ◽  
Flow Rate ◽  
Volume Flow Rate ◽  
Measurement Data ◽  
Volume Flow ◽  
Operating Conditions ◽  
Gear Pump ◽  
Industrial Sectors ◽  
External Gear Pumps ◽  
Gear Pumps

Gear pumps are used in numerous different applications and industrial sectors. However, when selecting a suitable gear pump for a specified application, manufacturers are often confronted with a lack of comparable measurement data for the desired combination of operating conditions and pumping fluid. Consequently, an estimation of the volume flow rate and the power consumption of a pump under the operating conditions of the application is necessary. In this context, this paper discusses the application of similarity on external gear pumps and presents its validation by means of measured pump characteristics. Seven gear pumps of different displacement volume are measured at different operating conditions varying pressure, rotational speed and the viscosity of the pumping fluid. The validation results prove that similarity is useful to represent a pump’s characteristic over a wide operating range. The prediction of the volume flow rate and the power consumption at a changed viscosity show good accuracy. However, the scaling of the pump characteristic based on the displacement volume show contradictory results.

Effect on Inlet Vent Porosity on Fan Characteristic Performance for Electronics Cooling

2009 ◽  
Author(s):  
Takashi Fukue ◽  
Katsuhiro Koizumi ◽  
Masaru Ishizuka ◽  
Shinji Nakagawa
Keyword(s):  
Flow Rate ◽  
Perforated Plate ◽  
Electronics Cooling ◽  
Maximum Flow ◽  
Flow Area ◽  
Flow Rates ◽  
Fan Performance ◽  
Performance Metric ◽  
Cooling Fans ◽  
The Relationship

Critical fan performance metric such as characteristic output curves and maximum flow rates are affected by various environmental conditions where cooling fans are installed. This paper describes the relationship between the fan performance and configuration factors such as the flow inlet porosity of electronic enclosure, the flow obstacles which imitate high-density packages and narrow flow area configurations. We installed a test enclosure in front of a test fan and measured P-Q curves of the test fan, which were operated in the enclosure. The experiments, it was observed that the pressure difference was increased in the enclosure by the effects of a wall. We installed a perforated plate in front of the fan as an obstacle and investigated how this changed the P-Q curve. In general, addition of the perforated plate in front of the fan decreased the characteristic output of the fan. On the other hand, the flow rate by the fan supply was decreased by the existence of the narrow inlet or obstacles. When an opening area in front of a fan became smaller than double of the fan flow area, the flow rate was significantly decreased. In addition, it was observed that the maximum flow rate depended on the opening area ratio. Finally, a model for predicting flow rates decreases by the enclosure inlet and obstacles was proposed.

Theoretical and Numerical Analysis on the Temperature Drop and Power Consumption of a Pre-Swirl System

2016 ◽  
Author(s):  
Gaowen Liu ◽  
Heng Wu ◽  
Qing Feng ◽  
Songling Liu
Keyword(s):  
Theoretical Analysis ◽  
Power Consumption ◽  
Mass Flow Rate ◽  
Mass Flow ◽  
Flow Rate ◽  
Temperature Drop ◽  
Cover Plate ◽  
Radial Location ◽  
Total Temperature ◽  
Cooling Air

As a component of delivering cooling air to turbine rotor blade at appropriate pressure, temperature and mass flow rate, pre-swirl system is very important to the cooling of turbine blades. It is attractive to the designers and scholars for its potential ability to reduce relative total temperature of cooling air as large as 100K. A pre-swirl system is actually an aero-thermodynamic system with energy transformation between work and heat. Theoretical analysis was carried out on an isentropic pre-swirl system to deduce equations for ideal temperature drop and power consumption. For an actual pre-swirl system, correlation between the actual temperature drop and power consumption was deduced, and a temperature drop effectiveness was defined also. Theoretical analysis shows that the system’s temperature drop increases linearly with the reduction of the power consumption. Numerical models were derived from a real engine pre-swirl system with small simplification. Standard k-ε turbulence model and Frozen-Rotor approach were applied in the three dimensional steady simulations. Inlet total pressure and total temperature, outlet static pressure, mass flow rate delivered to the blade and rotating speed of rotor were kept to be fixed for all the models. The influences of heat transfer and sealing flow coming from the inner seal were ignored in the simulations. Section averaged parameters like pressure, swirl ratio and total enthalpy were presented at each typical station throughout the flow path. The relationship between the temperature drop and the power consumption of all the models has been verified to be consistent with the deduced formula. For the pre-swirl system with low radial location of nozzle, these measures, such as adding impellers in the cover-plate cavity and inclining the receiver hole, were taken to reduce the power consumption and enlarge the temperature drop obviously. For this specific pre-swirl system, models with high radial location of nozzle are more recommended to decrease the loss caused by the large circumferential velocity difference between the airflow and the rotor.

Study on P-Q Curves of Cooling Fans for Thermal Design of Electronic Equipment (Effects of Opening Position of Obstructions Near a Fan)

2011 ◽  
Author(s):  
Takashi Fukue ◽  
Masaru Ishizuka ◽  
Tomoyuki Hatakeyama ◽  
Shinji Nakagawa ◽  
Katsuhiro Koizumi
Keyword(s):  
Flow Rate ◽  
Perforated Plate ◽  
Pressure Rise ◽  
High Density ◽  
Thermal Design ◽  
Electronic Equipment ◽  
Flow Passage ◽  
Fan Performance ◽  
Cooling Fan ◽  
Cooling Fans

This study describes an operation pressure and supplies flow rate of an axial cooling fan installed in high-density packaging electronic equipment. Fan performance is generally defined by their P-Q curve, specifically, a relationship between fan pressure rise (ΔP) and flow rate (Q). A compact cooling fan often operates in a high-density mounting device, which may decrease the fan performance. In this study, we focus on an obstruction near a fan, which is electronic components such as PCBs, capacitors and heat sinks, as one of a factor which decreases fan performance. We installed a perforated plate which simulated the above components near a fan and measured the P-Q curve. To investigate a relationship between a fan performance decrease and an opening position near the fan, a part of the perforated plate was closed. Closed position was changed and explored an opening condition which caused the dominant fan performance decrease. From experiments, it was found that the fan performance was decreased when flow passage in front of a fan was blocked by an obstruction. Especially, when flow passage in front of a fan hub was blocked, a dominantly reduction of fan pressure was caused. An obstruction rear a fan has no effect on a fan performance curve itself. In addition, opening conditions in front of a fan tip had a little influence on a fan pressure characteristic when there was no obstruction in front of a hub.

Stabilization of the Speed of the Hydraulic Motor Through Throttle Compensation for Volume Losses

2020 ◽  
Vol 26 (3) ◽  
pp. 126-130
Author(s):  
Krasimir Kalev
Keyword(s):  
Flow Rate ◽  
Hydraulic Drive ◽  
Pressure Change ◽  
Operating Conditions ◽  
Drive System ◽  
Inlet Pressure ◽  
Schematic Diagram ◽  
Hydraulic Characteristics ◽  
Hydraulic Motor ◽  
Flow Through

AbstractA schematic diagram of a hydraulic drive system is provided to stabilize the speed of the working body by compensating for volumetric losses in the hydraulic motor. The diagram shows the inclusion of an originally developed self-adjusting choke whose flow rate in the inlet pressure change range tends to reverse - with increasing pressure the flow through it decreases. Dependent on the hydraulic characteristics of the hydraulic motor and the specific operating conditions.

scholarly journals Evaporator Optimization of Refrigerator Systems Using Quality Analysis

Energies ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 555
Author(s):  
Sangkyung Na ◽  
Sanghun Song ◽  
Seunghyuk Lee ◽  
Jehwan Lee ◽  
Hyun Kim ◽  
...  
Keyword(s):  
Power Consumption ◽  
Operating Time ◽  
Cooling Capacity ◽  
Operating Conditions ◽  
Quality Analysis ◽  
Lubricating Oil ◽  
Optimal Operating ◽  
Compressor Piston ◽  
Refrigerator Temperature ◽  
Visualization Experiments

In this study, evaporator optimization, via both experimental and simulation methods was conducted. To evaluate the evaporator performance, under the optimal system, the compressor operating time and the effects of oil on the refrigerator system were studied. If the temperature of the refrigerator chamber reaches the setting value, the compressor stops working and it leads to the temperature of the refrigerator chamber slowly increasing, due to the heat transfer to the ambient. When the refrigerator temperature is out of the setting range, the compressor works again, and the refrigerator repeats this process until the end of its life. These on/off period can be controlled through the compressor piston movement. To determine the optimal compressor operating conditions, experiments of monthly power consumption were conducted under various compressor working times and the lowest power consumption conditions was determined when the compressor worked continuously. Lubricating oil, the refrigerator system, using oil, also influenced the system performance. To evaluate the effect of oil, oil eliminated and oil systems were compared based on cooling capacity and power consumption. The cooling capacity of the oil eliminated system was 2.6% higher and the power consumption was 3.6% lower than that of the oil system. After determining the optimal operating conditions of the refrigerator system, visualization experiments and simulations were conducted to decide the optimal evaporator and the conventional evaporator size can be reduced by approximately 2.9%.

scholarly journals Chemical–Electrochemical Process Concept for Lead Recovery from Waste Cathode Ray Tube Glass

Materials ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1546
Author(s):  
Árpád Imre-Lucaci ◽  
Melinda Fogarasi ◽  
Florica Imre-Lucaci ◽  
Szabolcs Fogarasi
Keyword(s):  
Flow Rate ◽  
Current Density ◽  
Complete Recovery ◽  
Electrochemical Process ◽  
Operating Conditions ◽  
General Effect ◽  
Optimal Operating ◽  
Recirculation Flow ◽  
Lead Recovery ◽  
Cathode Ray Tube

This paper presents a novel approach for the recovery of lead from waste cathode-ray tube (CRT) glass by applying a combined chemical-electrochemical process which allows the simultaneous recovery of Pb from waste CRT glass and electrochemical regeneration of the leaching agent. The optimal operating conditions were identified based on the influence of leaching agent concentration, recirculation flow rate and current density on the main technical performance indicators. The experimental results demonstrate that the process is the most efficient at 0.6 M acetic acid concentration, flow rate of 45 mL/min and current density of 4 mA/cm2. The mass balance data corresponding to the recycling of 10 kg/h waste CRT glass in the identified optimal operating conditions was used for the environmental assessment of the process. The General Effect Indices (GEIs), obtained through the Biwer Heinzle method for the input and output streams of the process, indicate that the developed recovery process not only achieve a complete recovery of lead but it is eco-friendly as well.

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