Design and construction of a concentrated solar furnace

This project is about the style and construction of a concentrated solar furnace. The basic aim of the report is to provide details about the design and style and operating principles of a solar furnace. The project utilized a parabolic concentrator and we designed the furnace in a cylindrical shape with steel for its body and an outer copper lid. To increase the efficiency of the furnace in this project, copper fins had been attached inside to improve heat transfer within the furnace. Following manufacturing and assembly, we tested the furnace with and without fins and there was a distinction noticed right after recordings accomplished at 20 minutes interval. The inner air temperatures recorded after 20 minutes was 55 without fins and 65 with fins. For the duration of the testing, the maximum temperature recorded inside the furnace was about 173 (air temperature) and 238 (fin tip temperature) these temperatures are high enough to be utilised in a variety of domestic applications such as cooking.

Background

Solar energy is undoubtedly the oldest source of energy. It is generally the radiant light and heat from the sun. We can even so trace all other types of power utilised on earth back to the sun. Harnessing the solar power has been the aim of various researches for several years. We think that sources for fossil based fuels such as oil and coal are limited and soon they will vanish. Many scientists are working to use solar energy for various purposes.

The history of solar energy is as old as mankind and more than the previous two centuries this energy has grow to be increasingly utilized either straight to make electrical energy or in applications to satisfy distinct demands of mankind. One of such applications is in the production of solar furnaces which could be used for a lot of purposes. A solar furnace is a structure that utilizes concentrated solar power to produce high temperatures, normally for market. Parabolic mirrors or heliostats concentrate light onto a focal point. The temperature at the focal point could reach extremely higher temperatures, and this heat can be utilised to generate electricity, melt steel, and make hydrogen fuel or nano-materials. A solar furnace makes use of reflectors to channel and concentrate solar power hence making heat. The sizes of solar furnaces could variety from tiny to huge depending on the desired heat demands. In the past, about the 7th century, men and women used magnifying glasses in simple form to generate concentrated light from the sun and use this domestically in producing wood to catch fire for cooking. Nevertheless more than the years, modifications and improvements in the field of technologies have led to the production of more sophisticated solar furnaces. The largest solar furnace is at Odeillo in the Pyrenees-Orientales in France, opened in 1970.

Objectives

The major aim of this project is to style and construct a functioning solar furnace. The main objective of the solar furnace design will be to produce heat from solar radiation as a high intensity energy supply for high temperature processes. In this project the aim is to make temperatures high adequate to be used in cooking applications whether for domestic or industrial utilizes. 1.three Limitations and Scope A viable choice for this technology is that which this project will be restricted to producing temperatures higher enough to result in combustion of wood (carbonization) and also efficient enough to aid cooking in properties. The constituents of a solar furnace will be nicely documented as the financial benefits of solar furnaces are massive. Nonetheless one particular constraint to its production is higher initial commence-up charges but conversely after started there is only tiny operational expenses required to continue. By replacing traditional furnaces, like electric arc and blast furnaces, with a solar furnace operating at high temperatures, carbon dioxide (CO2) emissions and energy consumption will be reduced greatly, which will better our society immensely. This project will discuss the topic of solar furnace in information by very first giving details of other investigation operate done on the subject- literature evaluation, then enumerating the methodology, design and style and calculations of this project and then ends with a conclusion and discussion part.

A Brief History Of Solar furnace

A solar furnace is not in fact a furnace but only implies an optical technique which has solar radiation been received from a collector and concentrates it into a small region. In a case where this highly concentrated radiant energy is channeled into a cavity, high temperatures are obtained due to the heat generated. Truly, it is this cavity that is the furnace and it represents a tiny portion of the entire program, therefore it is not out of place, to get in touch with solar furnaces: – solar power concentrators.

The concept of employing solar energy to generate high temperatures is not new. In 212 B.C. Archimedes presumably set fire to the Roman fleet by concentrating the sun’s rays on the ships by implies of numerous hundred plane mirrors. In the 17th and 18th centuries each mirrors and lenses had been used, and in 1772 Lavoisier constructed a furnace with a collecting lens getting a diameter of about five feet, in which he virtually reached the melting point of platinum (1773◦ C). Right after the perform of Lavoisier, till the beginning of the twentieth century, solar furnaces have been totally ignored. Nonetheless in 1921 Straubel and his collaborators at the Zeiss Organization in Germany constructed the first modern day reflecting furnace. This was completed with a glass parabolic mirror of about 6 feet diameter, and focal length of 2 feet at the finish temperatures above 3000◦C had been generated. This paved way for the use of distinct sizes of parabolic mirrors. Straubel had another collaborator in the particular person of W. Conn, he built a ten foot furnace and this was installed at Rockhurst College in Kansas USA. This furnace is created of aluminum alloy sheet and is still operational at Convair in San Diego and is used for higher temperature supplies studies. Much more so, searchlight mirrors of around five feet diameter are very good concentrators and are in operation in many laboratories in the United States.

The biggest installation of solar furnaces of a variety of sizes is positioned in Montlouis in the French Pyrenees. Professor FelixTrombe, head of the laboratory for the study of solar energy, has six furnaces in operation and these are produced of German parabolic searchlight mirrors. They are six.5 feet in diameter and also there is 1 huge furnace which is 35 feet in diameter. The massive size reflector is produced of 3500 smaller sized plane mirrors, attached to a steal frame which is parabolic in shape. To get a much better focusing, every single mirror used is bent mechanically and a curvature closes to 4 that of an excellent parabola is attained. Yet another bigger furnace has been produced, this is much more than 100 feet in diameter and after design and style its reflecting components have been tested. The energy of this large installation is about 1000kW. Additionally, Professor Guillemonat adopted W. Conn’s style and constructed a 27 feet diameter furnace in Algiers New Orleans. The parabola for this furnace was made of 144 panels of electro polished aluminum formed to the essential curvature. Other notable functions in this field contains that of the old soviet Russia, in which a huge solar energy study laboratory was installed close to Tachkent even so these were low temperature furnaces and no report has exists about solar furnaces made especially for higher temperatures. Lavoisier’s furnace was not the only a single built to concentrate the sun’s energy by implies of a lens. Amongst 1930 and 1932 the California institute of technology (Caltech) built a lens furnace and this was spear-headed by George Ellery Hale and its goal was to obtain high temperatures for spectroscopic research.This furnace is now positioned on the roof of the Caltech astrophysics department, and it is at present utilised for high temperature components investigation. Moreover, anybody conversant with the field of high temperatures will locate out that the performances of currently current solar furnaces are not spectacular. It is feasible to create temperatures within the variety of 3000◦ C by way of many diverse tactics: – these include, induction heating, melting in neutral atmosphere, electrical resistance heating, flames and so on. These techniques nonetheless have a limitation since they need a specific variety of atmosphere around the specimen below study. Whereas for the solar furnaces, heat source is in form of a cone of radiation energy that can be termed as pure heat and this does not impose any restriction to the sort of atmosphere that surrounds the specimen. An additional intriguing function of solar furnaces is that, the temperature obtainable at the focal region is concentrated and generates a high heat flux. Solar furnaces have the exclusive characteristic of being in a position to heat a body from inside to outside and this is valuable in melting refractory substances which react quite quickly with crucible materials at higher temperatures.

The Caltech furnace project tends to make use of the two outstanding functions mentioned above. The very first project is an investigation of highly refractory thorium oxide and zirconium oxide which have melting temperatures of 3200◦ C and 2700◦ C respectively. They melt these compositions in air at the focus of the furnace and assume oxidizing atmosphere about the melt. The second project is concerned with ceramic physique structures and it is primarily based on mixtures of titanium and zirconium dioxides, in which oxygen is usually decrease than it must be. The California institute of technologies (Caltech) solar furnace has nineteen lenses they are each two feet in diameter, arranged hexagonally and pointed towards the sun.