Preview

Thermoelectric Transducers

Satisfactory Essays
Open Document
Open Document
340 Words
Grammar
Grammar
Plagiarism
Plagiarism
Writing
Writing
Score
Score
Thermoelectric Transducers
Thermoelectric transducers

Thermoelectric transducers elements convert the change of measurand (temperatures) into the change of current, arising up because of difference of temperature on the junction of two heterogeneous materials, which an effect of Seebeck (fig. 17) is in. A thermoelectric transducers is anymore known under the name thermocouples, in which a probe consists of two junctions, one of which takes place in a point, where taking temperature is produced, and second - in the point of supporting temperature (fig. 18). Difference of potentials of V1 - V2 which appears on two junction (known as pin potentials), depends on the temperature of shuts and measured by a voltmeter. Thus, the testimonies of voltmeter represent the difference of temperatures between junction.

Fig. 17. Effect of Seebeck, at which in a chart, consisting of shuts of two heterogeneous metals, being at a different temperature, there is a current

Fig. 18. Principle, actions of thermocouple

Fig. 19. Typical dependences of tension on the difference of temperature for thermocouples the junctions of which are executed from different materials :
1 is a nickel-chrome/constantan (Е); 2 is iron/constantan (type of J), 3 is a copper/constantan (type of Т); 4 is a nickel-chrome/a nickel-manganese is aluminium-silicon (type of К); 5 platinum-rhodium/platinum (type of R) 6 is platinum-rhodium/platinum (type of S)

On a fig. 19 the tensions crooked, characterizing dependence are shown from the difference of temperatures for the row of typical materials which the junctions of thermocouples appear from. Although these dependences seem linear, the detailed researches show that it not quite so. In practice not so it is simple to attain necessary exactness of the temperature measuring by means of thermocouples, as it can appear from reasonings given above, as connection of voltmeter with a thermoelectric chart self on itself forms a new

You May Also Find These Documents Helpful

  • Good Essays

    Cold Pack Essay

    • 377 Words
    • 2 Pages

    Finally, the heat change for the calorimeter (qcal) will equal the measure temperature change (ΔT) times the heat capacity of the calorimeter using the…

    • 377 Words
    • 2 Pages
    Good Essays
  • Better Essays

    Me 224 Experiments

    • 2195 Words
    • 9 Pages

    Introduction The purpose of this lab is to build a temperature monitor and controller for a small aluminum block. Techniques involved in this lab include using transistors as switches, calibrating transducers, and writing control programs in LabVIEW. The main piece of equipment used in this lab is an aluminum block apparatus; the block has several holes drilled into it and embedded in them is a resistance heater, a thermistor, and a thermometer. In addition, a simple circuit is attached to the aluminum block with breadboarding for connection to the circuits built in the lab. The embedded resistance heater is used to heat the aluminum block. The heater is essentially a resistor that generates heat by the principle of Joule’s Law in which a current running through a resistor converts electrical energy into heat energy. Joule heating can be expressed by the relationship Q = I2 * R * t where Q is the heat (J) generated by a constant current I (A) flowing through a conductor of resistance R (Ω) for a given time t. [1] Although electric resistance heating converts nearly 100% of the electricity to heat, the overall process is still inefficient since the electricity is usually produced from oil, gas, or coal generators that convert only about 30% of the fuel’s energy into electricity. [2] Due to the energy loss in electricity generation and transmission, electric resistance heating is often more expensive than heat produced using combustion appliances, such as natural gas, propane, and oil furnaces. Thermistors are temperature sensing elements composed of sintered semiconductor materials such as silicon carbide that exhibit large changes in resistance in response to small changes in temperature. [3] Unlike most resistors, thermistors decrease in resistance as temperature increases because of their negative temperature coefficients as derived from their material properties. This relationship between resistance and temperature is better described by the equation…

    • 2195 Words
    • 9 Pages
    Better Essays
  • Good Essays

    Thermionic valves which were once used in computers, radios, and TVs were replaced by transistors. Compared to thermionic valves transistors:…

    • 342 Words
    • 2 Pages
    Good Essays
  • Good Essays

    The objective of this lab is to learn that whenever there is an electrical current in a conductor, there is some electrical energy that is converted into heat energy. The heat generated in an electrical circuit is commonly referred to as joule heat. Sir James Joule studies of these separate phenomena lead him to the discovery of the proportionality constant known as the Joule equivalent of heat, denoted by J. The Joule equivalent of heat is the amount of mechanical or electrical energy within a unit of heat energy. In many electrical applications joule heat is an undesirable loss of energy. However toasters and electrical heaters are purposefully converted into heat energy. In this experiment, the heating effect of electrical current and the electrical equivalent of heat will be investigated. The primary goal of this experiment is to show how the concept of heat energy relates to electrical energy…

    • 692 Words
    • 3 Pages
    Good Essays
  • Better Essays

    state (Houdas and Ring, 1982). Moreover, temperature coordination is closely related to the changes within the…

    • 1585 Words
    • 7 Pages
    Better Essays
  • Satisfactory Essays

    In Jennifer L. Pozner’s, “Dove’s “Real Beauty” Backlash” she discusses the problems that have occurred since the release of the “Real Beauty” campaign. Pozner begins her essay by setting up a scene at Madison Avenue, where she claims ads there objectify women and the products don’t; unlike Dove’s new “firming crèmes”, which objectify women. She illustrates an ad of a smiling diverse group of healthy, beautiful and voluptuous women that are happy with the way they look. However the ads for their new product that will help “correct” the pesky problem areas; makes Dove sound hypocritical since their whole campaign is about loving yourself the way you are naturally. So having products that rid of problem areas, basically send the message “love…

    • 353 Words
    • 2 Pages
    Satisfactory Essays
  • Satisfactory Essays

    4. Put the thermometer in each subject’s mouth and record the current temperature. (thermometer should be put inside the mouth because our mouth is internal part of our body and it is easier to measure the temperature)…

    • 389 Words
    • 2 Pages
    Satisfactory Essays
  • Better Essays

    In this laboratory you will study heat flow across a temperature gradient. By comparing the temperature difference across one material to the temperature difference across a second material of known thermal conductivity, when both are conducting heat at a steady rate, you will be able to calculate the thermal conductivity of the first material. You will then compare the experimental value of the calculated thermal conductivity to the known value for that material. Thermal conductivity is an important concept in the earth sciences, with applications including estimating of cooling rates of magma chambers, geothermal explorations, and estimates of the age of the Earth. It is also important in regard to heat transport in air, to understanding the properties of insulating material (including the walls and windows of your house), and in many other areas. The objective of this laboratory experiment is to apply the concepts of heat flow to measure the thermal conductivity of various materials.…

    • 1699 Words
    • 7 Pages
    Better Essays
  • Good Essays

    Country People

    • 769 Words
    • 4 Pages

    Was there ever a plan in your head that you were so confident in, yet it backfired on you? Hulga from “Good Country People” plans to destroy Manley Pointer’s emotions, but he ended up stealing her leg. Hulga deserves what she had gotten, because karma is out there, and even though Hulga did not destroy Manley Pointers faith her intentions were to destroy him, and that was bad enough. Hulga’s thoughts and steps towards destroying Manley Pointer ended up in a tragedy Hulga did not expect, yet this becomes a moment that can change Hulgas faith.…

    • 769 Words
    • 4 Pages
    Good Essays
  • Satisfactory Essays

    P2 Topics

    • 899 Words
    • 4 Pages

    14. Demonstrate an understanding of how the resistance of a thermistor changes with change of temperature (negative temperature coefficient thermistors only)…

    • 899 Words
    • 4 Pages
    Satisfactory Essays
  • Good Essays

    The hypothesis that when the temperature of a wire increases, the resistance value of the wire will also increase and the conductivity of the wire will reduce is proven to be true.…

    • 427 Words
    • 2 Pages
    Good Essays
  • Good Essays

    Physical properties

    • 973 Words
    • 4 Pages

    a) How the Drude model predicts that the conductivity of metals decreases as the temperature increases.…

    • 973 Words
    • 4 Pages
    Good Essays
  • Good Essays

    i) Assemble the apparatus as shown in the diagram. You need to build your immersion heater by winding the NiCr-wire around a pencil say 8 to 10 times.…

    • 912 Words
    • 7 Pages
    Good Essays
  • Powerful Essays

    Chemical Energetics

    • 13363 Words
    • 54 Pages

    Part 2: Basic thermodynamics: what you need to know . . . . . . . . . . . . . . . . . . 5…

    • 13363 Words
    • 54 Pages
    Powerful Essays
  • Good Essays

    Heat Transfer Lab Report

    • 927 Words
    • 4 Pages

    • 6 fix type K thermocouples and 2 type K thermocouples used only with brass Speciemen. Three thermocouples (T1, T2 and T3) are positioned along the heated section at uniform distance of 15 mm to measure the temperature transfer along the section. Three other thermocouples (T6, T7 and T8) are positioned along the cooled section at uniform distance of 15 mm to measure the temperature transfer along this section.…

    • 927 Words
    • 4 Pages
    Good Essays