A Miniature Double Oscillating-Fan Cooling System Using Electromagnetic Force

Author(s):  
Hsien-Chin Su

In this study, an oscillating-fan cooling device using electromagnetic force has been proposed. The device consists of two oscillating-fans flapping back and forth. It requires only one electromagnet and two elastic blades with one magnet on each of them. The electromagnet and two elastic blades are situated on a base and arranged accordingly. And thus, the electromagnetic force generated by the electromagnet can actuate the blades. The main advantage of this cooling device compared to a rotary fan is its simple structure because there is no bearing and motor in the cooling device. Moreover, the simplicity of the device makes it a highly reliable and low cost cooling device. The driving current can be either DC PWM or AC under 8 V – 12 V so it is compatible to most electronic devices. The dimensions of the cooling device can be designed as small as 20 mm (L) * 30 mm (W) * 4 mm (H) and as large as 60 mm * 55 mm * 25 mm. For a cooling experiment, three cooling devices with the dimension of 50 mm * 50 mm * 15 mm were incorporated with a heat sink with the dimension of 190 mm * 110 mm * 15 m. The dummy heater dissipated 55W while the environmental temperature is 44.8 °C. The result showed that the dummy heater can be cooled from 120.7 °C to 69.3 °C while the total power consumption of the three cooling devices is 1.74 W. The result shows that the cooling device not only provides an outstanding cooling ability but also shows a great potential for structural reliability and design flexibility.

2021 ◽  
Vol 11 (15) ◽  
pp. 6749
Author(s):  
Zhifeng Xie ◽  
Ao Wang ◽  
Zhuoran Liu

The cooling system is an important subsystem of an internal combustion engine, which plays a vital role in the engine’s dynamical characteristic, the fuel economy, and emission output performance at each speed and load. This paper proposes an economical and precise model for an electric cooling system, including the modeling of engine heat rejection, water jacket temperature, and other parts of the cooling system. This model ensures that the engine operates precisely at the designated temperature and the total power consumption of the cooling system takes the minimum value at some power proportion of fan and pump. Speed maps for the cooling fan and pump at different speeds and loads of engine are predicted, which can be stored in the electronic control unit (ECU). This model was validated on a single-cylinder diesel engine, called the DK32. Furthermore, it was used to tune the temperature of the water jacket precisely. The results show that in the common use case, the electric cooling system can save the power of 255 W in contrast with the mechanical cooling system, which is about 1.9% of the engine’s power output. In addition, the validation results of the DK32 engine meet the non-road mobile machinery China-IV emission standards.


Author(s):  
M. Sina Mousavi ◽  
Siamak Mirfendereski ◽  
Jae Sung Park ◽  
Jongwan Eun

The United Arab Emirates (UAE) is significantly dependent on desalinated water and groundwater resource, which is expensive and highly energy intensive. Despite the scarce water resource, only 54% of the recycled water was reused in 2015. In this study, an “Oasis” complex comprised of Sustainable Farming Compartments (SFCs) was proposed for reusing treated wastewater to decrease the ambient temperature of the SFC via an evaporative cooling system. A prototype SFC with half the original scale (width = 1.8 m, depth = 1.5 m, front height = 1.2 m back height = 0.9 m) was designed, built, and tested in an environmentally controlled laboratory and field site to evaluate the feasibility and effectiveness of the SFC under the climatic conditions in Abu Dhabi. Based on the experimental results, the temperature drops obtained from the SFC in the laboratory and field site were 5 ̊C at initial relative humidity of 60% and 7- 15 ̊C at initial relative humidity of 50%, respectively. An energy simulation using dynamic numerical simulations was performed in comparison to the results of the experiment. The energy-based dynamic simulation shows good agreement with the experimental results. The total power consumption of the SFC system was approximately three and a half times lower than that of an electrical air conditioner.


1972 ◽  
Vol 62 (4) ◽  
pp. 985-990 ◽  
Author(s):  
K. J. Muirhead ◽  
D. W. Simpson

Abstract A low-power, low-cost instrument using slow speed, direct recording on magnetic tape provides continuous unattended seismic recording in excess of 1 month. The seismic signal is recorded at two gain levels separated by 26 db with a total dynamic range of greater than 70 db. A high-accuracy crystal clock with fully coded digital output and a crystal stabilized radio for reference time-signal reception provide timing to better than 0.1 sec throughout the recording period. Total power consumption is less than 34 watts which enables operation for 1 month on dry cell batteries. The weight of the complete system including seismometer and batteries is less than 100 lb. Ten instruments have been used to record seismic signals ranging from localized microearthquake activity to explosions and teleseismic events.


Author(s):  
W Hijikata ◽  
T Mamiya ◽  
T Shinshi ◽  
S Takatani

In the field of rotary blood pumps, contactless support of the impeller by a magnetic bearing has been identified as a promising method to reduce blood damage and enhance durability. The authors developed a two-degrees-of-freedom radial controlled magnetic bearing system without a permanent magnet in the impeller in order that a low-cost disposable pump-head for an extracorporeal centrifugal blood pump could be manufactured more easily. Stable levitation and contactless rotation of the ‘magnet-free’ impeller were realized for a prototype blood-pump that made use of this magnetic bearing. The run-out of the impeller position at between 1000 r/min and 3000 r/min was less than 40 µm in the radial-controlled directions. The total power consumption of the magnetic bearing was less than 1 W at the same rotational speeds. When the pump was operated, a flow rate of 5 l/min against a head pressure of 78.66 kPa was achieved at a rotational speed of 4000 r/min, which is sufficient for extracorporeal circulation support. The proposed technology offers the advantage of low-cost mass production of disposable pump heads.


1996 ◽  
Vol 07 (04) ◽  
pp. 471-489 ◽  
Author(s):  
YUSUKE OTA ◽  
ROBERT G. SWARTZ ◽  
JOHN S. SCHAFER ◽  
MIHAI M. BANU ◽  
ALFRED E. DUNLOP ◽  
...  

A low cost digital optical receiver module for passive optical networks was developed. In order to reduce the cost of the receiver module, ICs are packaged in low cost plastic packages and the receiver module is fabricated using conventional surface mount technology. The receiver module is capable of receiving burst and packet digital optical signals, and recovered data and recovered clock in CMOS logic level are available. The receiver module contains a connectorized InGaAs PIN photodiode, a burst/packet mode-compatible preamplifier IC in a 32-lead TQFP plastic package, a comparator IC in an 8-lead SOIC plastic package, a clock recovery IC in a 32-lead TQFP plastic package and other active and passive components. These components are mounted on a four-layer printed wiring board. The intrinsic minimum receivable optical signal power is around -42 dBm/Ave and the dynamic range is over 26 dB for BER 1 × 10-8 at a bit rate of up to 60 Mb/s. The total power consumption of this module is less than 200 mW.


2020 ◽  
Vol 79 (16) ◽  
pp. 1479-1487
Author(s):  
Samarendra Nath Sur ◽  
A. K. Singh ◽  
P. Chettri ◽  
R. Bera
Keyword(s):  
Low Cost ◽  

Sensors ◽  
2021 ◽  
Vol 21 (11) ◽  
pp. 3713
Author(s):  
Soyeon Lee ◽  
Bohyeok Jeong ◽  
Keunyeol Park ◽  
Minkyu Song ◽  
Soo Youn Kim

This paper presents a CMOS image sensor (CIS) with built-in lane detection computing circuits for automotive applications. We propose on-CIS processing with an edge detection mask used in the readout circuit of the conventional CIS structure for high-speed lane detection. Furthermore, the edge detection mask can detect the edges of slanting lanes to improve accuracy. A prototype of the proposed CIS was fabricated using a 110 nm CIS process. It has an image resolution of 160 (H) × 120 (V) and a frame rate of 113, and it occupies an area of 5900 μm × 5240 μm. A comparison of its lane detection accuracy with that of existing edge detection algorithms shows that it achieves an acceptable accuracy. Moreover, the total power consumption of the proposed CIS is 9.7 mW at pixel, analog, and digital supply voltages of 3.3, 3.3, and 1.5 V, respectively.


Energies ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 3129
Author(s):  
Jewon Oh ◽  
Daisuke Sumiyoshi ◽  
Masatoshi Nishioka ◽  
Hyunbae Kim

The mass introduction of renewable energy is essential to reduce carbon dioxide emissions. We examined an operation method that combines the surplus energy of photovoltaic power generation using demand response (DR), which recognizes the balance between power supply and demand, with an aquifer heat storage system. In the case that predicts the occurrence of DR and performs DR storage and heat dissipation operation, the result was an operation that can suppress daytime power consumption without increasing total power consumption. Case 1-2, which performs nighttime heat storage operation for about 6 h, has become an operation that suppresses daytime power consumption by more than 60%. Furthermore, the increase in total power consumption was suppressed by combining DR heat storage operation. The long night heat storage operation did not use up the heat storage amount. Therefore, it is recommended to the heat storage operation at night as much as possible before DR occurs. In the target area of this study, the underground temperature was 19.1 °C, the room temperature during cooling was about 25 °C and groundwater could be used as the heat source. The aquifer thermal energy storage (ATES) system in this study uses three wells, and consists of a well that pumps groundwater, a heat storage well that stores heat and a well that used heat and then returns it. Care must be taken using such an operation method depending on the layer configuration.


2014 ◽  
Vol 722 ◽  
pp. 182-189
Author(s):  
Li Gang Ma ◽  
Chang Le Xiang ◽  
Tian Gang Zou ◽  
Fei Hong Mao

The paper proposes a cascade control strategy of speed feedback in inner loop and temperature feedback in outer ring for hydro-viscous driven fan cooling system, and compares the simulation of PID and fuzzy PID. The simulation result shows that the double-loop control system while the response time longer, but much smaller overshoot, can achieve a good feedback to adjust the fan speed and temperature and realize stepless speed regulation of hydro-viscous driven fan cooling system under the premise of stability for fan speed and system temperature.


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