Search results
Results from the WOW.Com Content Network
Increases heat transfer rates. Increases friction loses. Decreases entrance length. Reduces the difference between the laminar and turbulent heat transfer rates, in contrast to the straight tube case. The coil pitch S has negligible influence on the pressure drop and the heat transfer rates.
Heat transfer is a discipline of thermal engineering that concerns the generation, use, conversion, and exchange of thermal energy between physical systems. Heat transfer is classified into various mechanisms, such as thermal conduction, thermal convection, thermal radiation, and transfer of energy by phase changes.
Fins are extensions on exterior surfaces of objects that increase the rate of heat transfer to or from the object by increasing convection.This is achieved by increasing the surface area of the body, which in turn increases the heat transfer rate by a sufficient degree.
In the study of heat transfer, fins are surfaces that extend from an object to increase the rate of heat transfer to or from the environment by increasing convection. The amount of conduction, convection, or radiation of an object determines the amount of heat it transfers.
Harvesting that heat energy using a thermoelectric generator can increase the fuel efficiency of the car. Thermoelectric generators have been investigated to replace the alternators in cars demonstrating a 3.45% reduction in fuel consumption. [33] Projections for future improvements are up to a 10% increase in mileage for hybrid vehicles. [34]
describes heat transfer across a surface = Here, is the overall heat transfer coefficient, is the total heat transfer area, and is the minimum heat capacity rate. To better understand where this definition of NTU comes from, consider the following heat transfer energy balance, which is an extension of the energy balance above:
The role of a heat exchanger is to transfer heat between two mediums, so the performance of the heat exchanger is closely related to energy or thermal efficiency. [11] A counter flow heat exchanger is the most efficient type of heat exchanger in transferring heat energy from one circuit to the other [citation needed].
The macroscopic energy equation for infinitesimal volume used in heat transfer analysis is [6] = +, ˙, where q is heat flux vector, −ρc p (∂T/∂t) is temporal change of internal energy (ρ is density, c p is specific heat capacity at constant pressure, T is temperature and t is time), and ˙ is the energy conversion to and from thermal ...