The central objectives of this examination are to discover the warmth exchange convection and radiation together from a level barrel in typical convection over a broad assortment of power inputs and surface temperature. Moreover to take a gander at amidst convection and radiation heat trade and amidst Hc and Hr. Additionally, to choose the effect of obliged convection and to show the association between velocity and surface temperature for compelled convection. Likewise, demonstrate that the area heat trade coefficient shifts around the limit of a level barrel when subjected to obliged convection.
In Exp # 1, the voltage was continuously changing until the heater temperature (T10) reach the steady state condition and at this time, …show more content…
Heat trade is the strategy whereby heat moves beginning with one body or substance then onto the join by radiation, conduction, convection or a blend of these frameworks. Convection is the trading of warmth beginning with one place then onto the join by the movement of fluids. Convection is routinely the psyche boggling kind of warmth move in liquids and gasses. There are two sorts of convection warmth trade average and obliged. Trademark convection happens when mass smooth headways (steams and forward and in reverse improvements) are recognized by sensitivity powers while the compelled convection used when the streams and rehashing outlines in the fluid are influenced by outside means. Radiation heat trade is centrality transmitted by matter as electromagnetic waves.
III. Theoretical background:
Heat loss due to natural convection:
Qc = Hcm As (Ts-Ta) (1)
As = πDL (2) (3) (4) c and n are constant taken from table 1 page H2-4 in the lab manual (5) (6)
Hcm can be calculated by a simplified …show more content…
a. The voltage was set to 5V using the control box on the software screen.
b. T9, T10, V and I were recorded when the temperature reach the steady state condition.
c. The voltage was set to 8, 12, 15 and 20 volts and again T9, T10, V and I were recorded at each voltage.
a. The fan was set by using the control box to give an air velocity of 0.5 m/s while the voltage was kept constant at 20V.
b. Ua, T9, T10, V and I was recorded when the temperature reach the steady state.
c. The fan was adjusted to give an air velocity of 2,4 and 6 m/s and the same procedure was repeated.
a. The fan speed was set to give an air velocity of 1 m/s while the voltage was set at 20 V.
b. Angular position, Ua, T9, T10, V and I were recorded by rotating the cylinder by 30 degree if the temperatures reach the steady state condition.
c. The cylinder was rotated by 30 degree until it reached 180 degree and Angular position; Ua, T9, T10, V and I were recorded at each angle.
d. Finally, the fan was adjusted to give an air velocity of 5m/s and the above procedure was repeated.
Table 1: Experiment #1, theoretical and experimental values with its