An Experimental Investigation of a Stationary Reflector/Tracking Absorber Solar Collector at Intermediate Temperatures

1982 ◽  
Vol 104 (4) ◽  
pp. 340-344 ◽  
Author(s):  
E. Fruchter ◽  
G. Grossman ◽  
F. Kreith
Keyword(s):  
Low Temperatures ◽  
Solar Collector ◽  
Low Cost ◽  
Mineral Oil ◽  
Heat Transfer Fluid ◽  
Spherical Mirror ◽  
Present System ◽  
Intermediate Temperature Range ◽  
Design Construction ◽  
Stationary Reflector

This paper describes the design, construction, and testing of a concentrating solar collector based on the Stationary Reflector/Tracking Absorber (SRTA) principle. The system consists of a fixed, 2.5-m dia, spherical mirror which focuses solar radiation on a movable, cylindrical absorber tracking the sun. This work is an extension of earlier tests with a similar collector in which output temperatures up to 150°C were obtained with water. The present system, using a mineral-oil-based heat transfer fluid, was capable of heating the fluid up to 300°C under steady-state conditions. The direct radiation efficiency ranged from 50 percent at low temperatures up to 30 percent near 300°C, showing the SRTA to be an effective concentrating collector for the intermediate temperature range which can be constructed at relatively low cost.

scholarly journals LOW COST ALTERNATIVE SOLAR COLLECTOR WITH ABSORPTION SURFACE FORMED BY PVC TUBES

2007 ◽  
Vol 6 (1) ◽  
pp. 57
Author(s):  
L. G. M. Souza ◽  
R. D. Santos ◽  
H. J. L. Neto
Keyword(s):  
Solar Radiation ◽  
Low Temperatures ◽  
Solar Collector ◽  
Low Cost ◽  
Glass Wool ◽  
Thermal Isolation ◽  
New Model ◽  
Conventional Systems ◽  
Multiple Units ◽  
Water Exit

A no conventional new model of solar collector is presented, composed for multiple units of PVC tubes in parallel to absorb solar radiation, through a new model of linking between same and the pipes of admission and water exit. The collector’s box is made with a composite of matrix ceramic and coated with resin, propitiating the elimination of the thermal isolation, usually glass wool.  The collector is composed of only three elements: the box, the absorb grid and glass. It will board constructive aspects, demonstrating the easiness to manufacture such archetype that is characterized for presenting a cost of manufacture sufficiently reduced. It will be presented values of thermal parameters of the collectors, working in regimen of thermosiphon in a volume of water in the order of 250 liters (66.03 gallons). One will demonstrate the thermal, economic and the materials viability of this collector, enabling it to serve as another option to the conventional systems of market heating, mainly to the attainment of low temperatures.

Design, Construction, and Analysis of a Passive Indirect Solar Dryer With Chimney

2018 ◽  
Vol 141 (3) ◽  
Author(s):  
Felipe Cichetto Tedesco ◽  
Alexandre José Bühler ◽  
Sérgio Wortmann
Keyword(s):  
Solar Collector ◽  
Low Cost ◽  
Payback Period ◽  
Coefficient Of Performance ◽  
Rio Grande Do Sul ◽  
Alternative Technologies ◽  
Solar Dryer ◽  
Great Production ◽  
Design Construction ◽  
Seeds And Fruits

The growing demand for alternative technologies, of clean and sustainable nature, has fostered the development and improvement of equipment that uses solar energy for the dehydration of seeds and fruits. Such equipment has been used worldwide for hundreds of years; however, it remains uncommon in Serra Gaúcha, a region of great production of grapes and apples for natura consumption in the state of Rio Grande do Sul—Brazil. In order to investigate the economic and technical viability of solar dryers in the Serra Gaúcha, this work has as target the design, simulation, construction, and experimental analysis of an Indirect Passive Solar Dryer with Chimney. The prototype, divided into three parts: solar collector, dehydration chamber, and chimney, was built prioritizing materials of low cost, but that did not compromise its performance. The device was submitted to experiments, which observed: solar collector behavior very close to the simulated one; obtaining a coefficient of performance of 87% in the equipment; satisfactory rise in temperature at the collector outlet comparing to its inlet; and dehydration of apples with a reduction of 89% in mass with 32.78 MJ of energy delivered to the system. The prototype payback period was estimated in two years.

Experimental Study of Single-Slope Solar Still Coupled With Nanofluid-Based Volumetric Absorption Solar Collector

2021 ◽  
Vol 144 (1) ◽  
Author(s):  
Jagteshwar Singh ◽  
M. K. Mittal ◽  
Vikrant Khullar
Keyword(s):  
Solar Energy ◽  
Solar Collector ◽  
Low Cost ◽  
Engine Oil ◽  
Heat Transfer Fluid ◽  
Working Fluid ◽  
Solar Still ◽  
Surface Absorption ◽  
Paraffin Oil ◽  
The Given

Abstract In the present endeavor, a conventional single-slope solar still has been modified to improve its performance by coupling it with a novel nanofluid-based volumetric absorption solar collector (NBVASC). A low-cost and thermally stable nanofluid (prepared by dispersing functionalized carbon soot nanoparticles extracted from used engine oil into paraffin oil) having high solar weighted absorptivity has been employed to volumetrically absorb the incident solar energy. This additional absorbed solar energy is provided to the solar still by circulating a heat transfer fluid in a closed loop through serpentine type heat exchangers placed inside the NBVASC and the solar still. The experiments were performed from May to July 2020, and the results of the experiments conducted on May 25 and June 9, 2020, are reported. Extensive on-sun experiments reveal that coupling NBVASC to the conventional still could lead to substantial performance enhancements—distillate productivity, thermal efficiency, and night distillate improved by 75.3%, 66.9%, and 33.9%, respectively. More importantly, solar still coupled to NBVASC was found to perform better at an optimum nanoparticle concentration of 1.25 mlL−1 (20.75% higher distillate productivity) than the solar still coupled to a surface absorption-based collector (with paraffin oil as the working fluid)—truly establishing the benefits of volumetric absorption over surface absorption under the given set of conditions. Overall, the present study represents a noteworthy step forward in realizing efficient solar energy-driven desalination systems for remote underdeveloped areas.

scholarly journals Performance of cylindrical parabolic solar collector with the tracking system

2021 ◽  
Vol 3 (1) ◽  
pp. 20-24
Author(s):  
M. Anil Kumar ◽  
K. Sridhar ◽  
B. Devika
Keyword(s):  
Heat Transfer ◽  
Solar Collector ◽  
Fundamental Problem ◽  
Tracking System ◽  
Low Cost ◽  
Radiant Energy ◽  
Heat Transfer Fluid ◽  
Project Work ◽  
Design Development ◽  
Parabolic Trough

A parabolic solar collector collects the radiant energy emitted from the sun and focuses on a point. Parabolic trough collectors are the low-cost implementation of concentrated solar power technology that focuses incident sunlight onto a tube filled with a heat transfer fluid. However, the fundamental problem with the cylindrical parabolic collector without tracking was that the solar collector does not move with the sun's orientation. The development of an automatic tracking system for cylindrical parabolic collectors will increase solar collection and the efficiency of devices. The present study of this project work presents an experimental platform based on the design, development, and performance characteristic of water heating by tracking solar cylindrical parabolic concentrating system. The tracking mechanism is to be made by stepper motor arrangement to receive the maximum possible energy of solar radiation as it tracks the sun's path. The performance of the parabolic trough collectors is experimentally investigated with the water circulated as heat transfer fluid. The collector efficiency is calculated.

Terrestrial Heat Repository for Months of Storage (THERMS): A Novel Radial Thermocline System

2021 ◽  
Author(s):  
Clifford K. Ho ◽  
Walter Gerstle
Keyword(s):  
Heat Transfer ◽  
Low Cost ◽  
Storage System ◽  
Electrical Heating ◽  
Heat Transfer Fluid ◽  
Present System ◽  
System Sensitivity ◽  
Thermal Plant ◽  
And Performance ◽  
The Impact

Abstract This paper describes a terrestrial thermocline storage system comprised of inexpensive rock, gravel, and/or sand-like materials to store high-temperature heat for days to months. The present system seeks to overcome past challenges of thermocline storage (cost and performance) by utilizing a confined radial-based thermocline storage system that can better control the flow and temperature distribution in a bed of porous materials with one or more layers or zones of different particle sizes, materials, and injection/extraction wells. Air is used as the heat-transfer fluid, and the storage bed can be heated or “trickle charged” by flowing hot air through multiple wells during periods of low electricity demand using electrical heating or heat from a solar thermal plant. This terrestrial-based storage system can provide low-cost, large-capacity energy storage for both high- (∼400–800°C) and low- (∼100–400°C) temperature applications. Bench-scale experiments were conducted, and computational fluid dynamics (CFD) simulations were performed to verify models and improve understanding of relevant features and processes that impact the performance of the radial thermocline storage system. Sensitivity studies were performed using the CFD model to investigate the impact of the air flow rate, porosity, particle thermal conductivity, and air-to-particle heat-transfer coefficient on temperature profiles. A preliminary technoeconomic analysis was also performed to estimate the levelized cost of storage for different storage durations and discharging scenarios.

Low Temperature Fault Isolation Using Soft Defect Localization

2012 ◽  
Author(s):  
Kristopher D. Staller
Keyword(s):  
Low Temperatures ◽  
Laser Scanning ◽  
Low Cost ◽  
Fault Isolation ◽  
Laser Scanning Microscopy ◽  
Cold Temperature ◽  
Multiple Point ◽  
Defect Localization ◽  
Low Levels

Abstract Cold temperature failures are often difficult to resolve, especially those at extreme low levels (< -40°C). Momentary application of chill spray can confirm the failure mode, but is impractical during photoemission microscopy (PEM), laser scanning microscopy (LSM), and multiple point microprobing. This paper will examine relatively low-cost cold temperature systems that can hold samples at steady state extreme low temperatures and describe a case study where a cold temperature stage was combined with LSM soft defect localization (SDL) to rapidly identify the cause of a complex cold temperature failure mechanism.

scholarly journals Process Emulation System for High-Power Piezoelectric Ultrasonic Actuators

2015 ◽  
Vol 2 (3-4) ◽  
pp. 201-205
Author(s):  
Igor Ille ◽  
Sebastian Mojrzisch ◽  
Jens Twiefel
Keyword(s):  
Feedback Control ◽  
Low Cost ◽  
Stable Process ◽  
Present System ◽  
Wide Field ◽  
Hardware In The Loop ◽  
Ultrasonic Assisted ◽  
Long Time ◽  
Number Of Cycles ◽  
High Flexibility

Abstract Ultrasonic actuators are used for a wide field of applications. The vibration energy can be used to realize many processes like ultrasonic welding or bonding. Furthermore there are many processes which run more efficient and faster combined with ultrasonic vibration like ultrasonic-assisted turning or drilling. Piezoelectric transducers are the main part of those applications. Most of the applications have a time-variant load behavior and need an amplitude feedback control to guarantee a stable process. To ensure correct function tests of the feedback control systems have to be done. In this case the processes have to be executed in association with a high number of cycles. To emulate the behavior of the environment the automotive and aerospace industries use hardware in the loop systems since a long time but there is no such a method for ultrasonic systems. This paper presents a method to realize high dynamic load emulation for different ultrasonic applications. Using a piezoelectric transformer it is possible to reproduce load curves by active damping on the secondary side of the transformer using a current proportional digital feedback circuit. A theoretical and experimental study of hardware in the loop system for ultrasonic applications is given by this paper. The present system allows testing a wide field of feedback control algorithms with high flexibility and a high number of cycles by utilization of low-cost components. This proceeding decreases design periods in association with feedback control.

scholarly journals Design and construction of low-cost respiration chambers for ruminal methane measurements in ruminants

2017 ◽  
Vol 8 (2) ◽  
pp. 185 ◽  
Author(s):  
Jorge Rodolfo Canul Solis ◽  
Angel Trinidad Piñeiro Vázquez ◽  
Jeyderl Israe Arceo Castillo ◽  
José Alayón Alayón Gamboa ◽  
Armín Javier Ayala Burgos ◽  
...  
Keyword(s):  
Methane Production ◽  
Low Cost ◽  
Bos Indicus ◽  
Mass Action ◽  
Pennisetum Purpureum ◽  
Air Conditioner ◽  
Tropical Regions ◽  
In Vivo Measurement ◽  
Design Construction

ABSTRACTRuminant animals contribute significantly to methane emissions in tropical regions. Nonetheless, there are few facilities available in those regions of the world for in vivo measurement of methane production in cattle. The aim of the present work was to describe the design, construction and operation of respiration chambers for in vivo measurement of methane production in cattle in Mexico. Locally available materials were used in the construction. Walls, roof and doors were constructed of thermic panels with two windows of acrylic at the front so the animal can be observed at all times. Chambers have an air volume of 9.97 m3. Air is drawn from the chamber at a rate of 500 L/min by the effect of mass action flow generators. Methane was measured in air samples with an infrared analyzer. Chambers operate under a slight negative pressure of around -500 Pa. Air temperature inside the chambers is kept at 23 °C with an air conditioner, while relative humidity is maintained at 55 % with a dehumidifier. Functioning of the chambers was evaluated in Bos indicus, Nelore cattle fed Taiwan grass (Pennisetum purpureum) and a concentrate (18 % crude protein), and measurements were made during runs of 23 h duration. Methane production was on average 173.2 L per day, while the emission factor was 17.48 L methane per kilogram o dry matter consumed. It concludes that this respiration facility is capable of measuring methane production accurately in cattle fed tropical rations.

Sign in / Sign up

Export Citation Format

Share Document