What affects the rate of heat transfer?
Factors that affect rate of heat flow include the conductivity of the material, temperature difference across the material, thickness of the material, and area of the material. Different materials have greater or lesser resistance to heat transfer, making them better insulators or better conductors.
How can you increase the rate of heat transfer?
Replacing the inner metal can with a glass jar or a Styrofoam cup would change the rate of heat transfer. The rate of heat transfer depends on the material through which heat is transferred. The effect of a material upon heat transfer rates is often expressed in terms of a number known as the thermal conductivity.
What is a good heat transfer coefficient?
As mentioned earlier in the article the convection heat transfer coefficient for each stream depends on the type of fluid, flow properties and temperature properties. Some typical heat transfer coefficients include: Air – h = 10 to 100 W/(m2K) Water – h = 500 to 10,000 W/(m2K).
What is the difference between thermal conductivity and heat transfer coefficient?
All Answers (3) Heat transfer coefficient is proportionality constant between heat supplied and thermodynamic driving force of heat flow through the per unit area with change in wall temperature. The thermal conductivity of the fluid is related to the spatial molecular diffusion of heat throughout the fluid.
What is the difference between fin efficiency and fin effectiveness?
Therefore, the fin effectiveness can be determined easily when the fin efficiency is known, or vice versa. The thermal conductivity k of the fin material should be as high as possible. The overall effectiveness is a better measure of the performance of a finned surface than the effectiveness of the individual fins.
Which fin is more effective?
If the ratio of P and Ac is increased , the effectiveness of fin is improved. Use of fin will be more effective with materials of large thermal conductivities.
How do you increase the efficiency of a fin?
Increasing the diameter of a fin increases its efficiency but decreases its effectiveness. Chapter 3, Solution 108C. The thicker fin has higher efficiency; the thinner one has higher effectiveness.