methods of heat transfer conduction

... Trang 1Proceedings of NHTC'01 35th National Heat Transfer Conference Anaheim, California, June 10-12, 2001 NHTC2001-20070 MOLECULAR DYNAMICS SIMULATION OF HEAT TRANSFER AND PHASE CHANGE ... with 160,000 atoms Heat conduction by the electron gas, which dominated heat transfer in metal, could not be predicted by the Morse potential function Alternatively, heat conduction was simulated ... the surface of the target by scaling velocities of atoms in cells on the top surface, and the same amount of heat flux is dissipated from the bottom of the target by scaling velocities of atoms

Ngày tải lên: 06/05/2014, 08:55

... In this study the heat transfer coefficient of condenser and evaporator and the heat transfer limits were investigated The analytical heat transfer coefficient and the heat transfer limits and ... 5 shows the experimental data of Noie [10] for heat transfer coefficient of evaporator Figure 5 Heat transfer coefficient of evaporator versus average temperature of evaporator surface for different ... with small fill rates, Heat Recovery Systems,7(4), pp 319-327 [6] Busse, C.A., (1973) Theory of ultimate heat transfer limit of cylindrical heat pipes Int J Heat and Mass Transfer,16, pp 169-186

Ngày tải lên: 09/09/2015, 10:32

... Carnot heat engine of the same heat input, the generalized irreversible Carnot engine can deliver less power and release more heat to the heat sink Hence, the rate of heat flow (QLC) to the heat ... surface areas of high- and low-temperature side heat-exchangers The total heat transfer surface area of the two heat exchangers is taken as a constant , that is T F F And a ratio ( f ) of heat exchanger ... profit rate and efficiency of the irreversible Carnot heat engine based on the radiative heat transfer law The relationships between the profit rate and efficiency of the irreversible Carnot heat

Ngày tải lên: 09/09/2015, 10:32

... without the presence of the wall; they attributed this phenomena to the distortion of velocity field by the wall and consequent alteration of the heat transfer characteristics of the hot wire such ... electrically heated sensing probe The variation of heat loss from the thermal element can be interpreted as a measure of the fluid velocity changes There are two fundamentally different types of thermal ... response of the hot wire has enable the faithful measurement of fluctuating velocity in the typical range of frequency and amplitude encountered in a turbulent flow Trang 8C p Specific heat of fluid

Ngày tải lên: 16/09/2015, 17:14

... study of heat transfer and thermal performance with longitudinal fins of solar air heater Foued Chabane a,b,* , Noureddine Moummi a,b, Said Benramache a,c a Mechanical Department, Faculty of Technology, ... coefficient (W/m2K) Cp specific heat of air (J/kg K) Ac area of absorber plate surface (m2) i position of the thermocouple connected of 1–4 DT temperature difference (C) t time of the during day (h) Vf ... air heater Increasing the area of the ab-sorber plate shape will increase the heat transferred to the fol-lowing air Collector thermal efficiency The efficiency of a solar collector is the ratio of

Ngày tải lên: 13/01/2020, 11:50

... was observed in the critical values of ‘Jingxiu’, ‘Riesling’ and spine grape: heat injury of grapevines The comparison of investigation methods for heat injury of grapevines under Tc and OJIP test ... after 10 min of heat stress but rapidly decreased values than did‘Jingxiu’ Evaluation of heat tolerance in 47 cultivars (or species) of grapevine under Tc Generally, heat injury under heat temperature ... of Plant Resources and Beijing Key Laboratory of Grape Science and Enology, Institute of Botany, the Chinese Academy of Sciences, Beijing 100093, People's Republic of China 4 Key Laboratory of

Ngày tải lên: 27/05/2020, 02:07

... radiative heat transfer equation The negative sign in the rate of heat transfer indicates that the sphere is gaining heat from the surrounding wall Trang 30Note that the rate of heat transfer ... surface temperature of the sphere A calculation of the total rate of heat transfer to the sphere would have to take the rate on condensation and the rate of radiative heat transfer into account ... equal to the heat lost by convection The rate of heat transfer by convection is given by Equation (1.10) qc = h c A Δ T = h c π D L (T p – T G) For steady state to exist the rate of heat transfer

Ngày tải lên: 21/08/2020, 09:48

... rate of heat transfer by convection (Equation (1.10)) from the outer surface must be the same as the rate of heat transfer by conduction through the glass  This value for the convective heat transfer ... the heat loss through the two specimens must equal the power dissipation of the heater Therefore the heat transfer through one of the specimens is q h/2 For one dimensional, steady state conduction ... For steady state to exist the rate of heat transfer by convection must equal the rate of heat transfer by radiation Trang 21PROBLEM 1.16 Water at a temperature of 77°C is to be evaporated slowly

Ngày tải lên: 21/08/2020, 13:29

... the influence of noise in measured temper-ature data, improving the stability of inverse heat transfer analysis Consequently, the benefit of the employment of POD in inverse heat transfer problems ... no heat sink/source, the governing equation of steady-state heat transfer in the bodyΩ is written by where T is the temperature and k is the thermal conductivity Without consideration of heat ... However, to the best knowledge of the authors, GWO has not been investigated in inverse heat transfer analysis During the search for optimum solution, the direct heat transfer problems have to be

Ngày tải lên: 28/06/2021, 11:18

... years.Two important conditions for modelling a heat transfer process are the law of heattransfer on the boundary of the object and heat sources generated heat conduction.These conditions are generated ... Learning Resource Center of Thai Nguyen University - Library of the College of Education – Thai Nguyen University Trang 3The process of heat transfer or diffusion are often modelled by boundary ... Trang 1MINISTRY OF EDUCATION AND TRAININGTHAI NGUYEN UNIVERSITY BUI VIET HUONG DETERMINATION OF NONLINEAR HEAT TRANSFER LAWS AND SOURCES Trang 2Scientific supervisor: Prof Dr habil Dinh Nho

Ngày tải lên: 16/01/2020, 04:19

... -6.4648 4.4 Rate of heat transfer The rate of heat transfer at the wall i.e the heat flux in terms of Nusselt number N u for different values of α and K p are entered in Table 2 The heat flux at ... z-components of skin friction at the wall become B m τ 1 1 3 2 4 5 , (50) z sin A A 1 2 π εα τ = − (51) 3.2 Rate of heat transfer The rate of heat transfer i.e heat flux at the wall in terms of Nusselt ... and the rate of heat transfer are discussed with the help of figures and tables Copyright © 2010 International Energy and Environment Foundation - All rights reserved Keywords: Heat transfer, Periodic

Ngày tải lên: 05/09/2013, 14:58

... optimal expansion of a heated working fluid with convective radiative heat transfer [7] and to investigate the effects of variable specific heat ratio of working fluid on the performance of an irreversible ... Fine-time exergoeconomic performance of a Newtonian heat transfer law system generalized irreversible combined heat pump with irreversibility of finite-rate heat transfer, heat leakage and internal irreversibility ... A is the heat transfer area, h is the convection heat transfer coefficient between the working fluid and the reservoir, and t is the time of releasing heat process. The radiation heat transfer

Ngày tải lên: 05/09/2013, 15:28

... overall heat transfer coefficient and F1 is the heat-transfer surface area of the high- temperature-side heat exchanger , β is the overall heat transfer coefficient and F2 is the heat-transfer ... deriving force of T H −T HC, Q LC is the rate of heat flow from working fluid to the heat sink due to the deriving force of T LC −T L, Q H is rate of heat transfer supplied by the heat source, ... HC>T LC >T L The heat-transfer surface areas (F1 and F2 ) of high- and low-temperature heat exchangers are finite The total heat transfer surface area (F) of the two heat exchangers is assumed

Ngày tải lên: 05/09/2013, 15:28

... equation describes the absorption of heat by the electron system from the laser, the heat diffusion among the electrons, and transfer of heat to the lattice S is the laser heating source term, defined ... model looks at the heating mechanism as consisting of three processes: the absorption of laser energy by the electrons, the transport of energy by the elec-trons, and heating of the lattice by ... phase has a large amount of superheating and that a distinct melt phase develops with duration of the order of nanoseconds. INTRODUCTION In the last few years, the use of femtosecond lasers in

Ngày tải lên: 06/05/2014, 08:53

... 0.44 power of Grashof number The heat transferred to the working fluid via substrate heat conduction was found to account for 41–47% of the heat removal from the ribs The optimum position of a discrete ... thermal behavior of the ink, primer and paint, heating in biothermal systems, and RBF finite difference approach in heat conduction The third section includes heat transfer analysis of reinforced ... beam, modeling of heat transfer and phase transformations, boundary conditions-surface heat flux and temperature, simulation of phase change materials, and finite element methods of factorial design

Ngày tải lên: 19/06/2014, 10:20

... occurs as a result of two competing mechanisms. The Convection and Conduction Heat Transfer 58 first is due to shear flow caused by the movement of one of the walls of the cavity while ... and heat transfer process. 1.3 Motivation behind the selection of problem Two dimensional steady, mixed convection heat transfers in a two-dimensional trapezoidal cavity with constant heat ... the heat transfer process is analyzed in terms of average Nusselt number. Contextually the present study will focus on the computational analysis of the influence of inclination angle of the

Ngày tải lên: 19/06/2014, 10:20

... to better cooling effect • The direction of the motion of the lid also affects the heat transfer phenomena Aiding flow condition always gives better heat transfer rate than opposing flow condition ... Convection heat transfer in electronic equipment cooling, J.Heat Transfer 110 (1988) 1097–1111 [5] C K Cha and Y Jaluria, Recirculating mixed convection flow for energy extraction, Int j Heat Mass Transfer ... on laminar mixed convection heat transfer in a lid-driven cavity, Int J Heat Mass Transfer 35 (1992) 1881–1892 [19] A.A Mohammad, R Viskanta, Laminar flow and heat transfer in Rayleigh–Benard

Ngày tải lên: 19/06/2014, 10:20

... early stages of phase change simulations of metal like materials where the oscillatory “steady-state” develops 2.2 Porous media natural convection A variant of the test, where instead of the free ... However, this chapter is focused on one of the simplest classes of meshless methods in development today, the Radial Basis Function (Buhmann, 2000) Collocation Methods (RBFCM) (Šarler, 2007) The meshless ... Navier-Stokes equation is of the second order while the Darcy equation is of the first order and therefore different boundary conditions for the velocity apply Instead of the no-slip boundary condition

Ngày tải lên: 19/06/2014, 10:20

... terms of the thermal field, the tilting of isotherms was observed. Finally the effects of combined radiation and a magnetic field on the convective flow and heat transfer characteristics of an ... dominant mode of heat transfer and surpassed convective heat transfer so that it played an important role in developing the hydromagnetic free convective flow in a differentially heated enclosure. ... Conduction Heat Transfer in which Tmin and Tmax are correspondingly the smallest and biggest of all values of the temperatures, encountered in the initial and boundary conditions of

Ngày tải lên: 19/06/2014, 10:20

... value of turbulent intensity is observed at the relative gap width of 1.0 which is in the line of heat transfer measurements. These results of PIV showed good agreement between the heat transfer ... Investigation of heat transfer and friction for rib- roughened surfaces, Int. Journal of Heat & Mass Transfer 1978; 21: 1143-1156. [4] Webb R.L., Eckert E.R.G. and Goldstein R. J. Heat transfer ... Journal of Heat and Mass Transfer1 999; 42: 1597-1615. [16] Karwa R, Experimental studies of augmented heat transfer and friction in asymmetrically heated rectangular ducts with ribs on the heated...

Ngày tải lên: 05/09/2013, 16:10