Three-dimensional direct numerical simulation (DNS) of turbulent hydrogen-air premixed flames in a constant volume vessel at relatively high Reynolds numbers have been conducted considering detailed kinetic mechanism and temperature dependence of the transport and thermal properties. The flame behavior and ...
For the steady state modeling of heat transfer, we consider a constant value for rinf. For use of the model in a transient situation, rinf is calculated at each depth and time using an empirical equation suggested by Carslaw and Jaeger (1959). Heat transfer between the well fluid with ...
Two types of heat transfer phenomena can be considered in analyzing the heat exchange process, namely steady-state and unsteady-state heat transfer [1]. Under steady-state heat transfer conditions, the temperature within the system does not change with time, i.e., a constant heat transfer rate...
It should be noted that at low values of the TTD of the heater, the amount of fresh water can be enhanced more significantly than is the case when the system works at higher TTDs of the heater. That is, when decreasing the TTD of the heater with a constant decrement step of 5 K, ...
The hydraulic diameter of the middle tube at the top of the heat exchanger is then determined considering a constant volume for the PCM equal to the PCM volume in the straight triplex tube heat exchanger. It should be noted that in the case of changing the inner tube to a frustum tube, ...
1 Heat transfer through the window is steady since the surface temperatures remain constant at the specified values. 2 Heat transfer through the wall is one-dimensional since any significant temperature gradients will exist in the direction from the indoors to the outdoors. 3 Thermal conductivity...
“incident” fields or input-1:A1r/r1and input-2:A2r2/r. Heat transfer through a conductive system is usually studied by maintaining constant temperatures at the left and right sides (T= ±A1r0/r1atrcosθ= ±r0) and thermally insulating the upper and lower sides. If the object is ...
Here we theoretically show consistent analytical expressions for the advective constant and convective heat transfer coefficients determined from the proposed general 3D energy transfer theory of thermal convection. By recasting a control volume system into an equivalent control mass system and employing the...
so it is possible to setAas constant (=1), and assuming always the same liquidcpand hence the same densityρand set both as well as constant(=1). As the mass flow may be calculated with dm = dv xρ (volume flow times density)we will get the "qualitative" Heat transfer coefficientα...
Frontiers in Heat and Mass Transfer is a free-access and peer-reviewed online journal that provides a central vehicle for the exchange of basic ideas in heat and mass transfer between researchers and engineers around the globe. It disseminates informatio