Search results
Oct 9, 2001 · The outside heat transfer coefficient is critical to estimating the insulation surface temperature. The heat transfer across the insulation from the inside temperature to the outside surface temperature equals the heat transfer to the ambient air. The lower this coefficient, the higher the skin temperature is required.
May 30, 2006 · Heat transfer coefficient are very much situational dependent and are very sensitive to the surface conditions involved. Normally it is difficult to take into account these surface anomalities using the emperical or estimated values and you will end up with an order of magnitude different values than the real values for your system.
Apr 30, 2000 · The heat transfer coefficient will depend on the properties of the air near the surface of the earth. You will need to estimate the temperature of the air to the get the air properties. Then you will need to assume or know an air velocity to estimate h.
May 17, 2012 · the U (overall heat transfer coefficient) can be written in a function of one of the fluidums mass rate when I keep the other fluidum's mass rate constant: so U(mass rate fluidum 1)=(a*M+b)/(M+c). So its a rational function with both first order polynoms. And when I curve fitted it from my experimental data, it had an R square of at least 0,999.
The convection heat transfer coefficient on its surface is 6 W/m2°C. Assuming the apple as a sphere having a diameter of 10-cm and taking its properties as p = 750 kg/m³, p = 2850 J/kg°c, and k = 0.450 W/m°C, determine; (a) the center temperature of the apple in 45 minutes, (b) the actual amount of heat transfer from the apple, and (c) the final equilibrium temperature of the apple.
May 28, 2008 · Extending the external heat transfer coefficient up to around 250 shows that the heat transfer reaches an asymptote well within the suggested upper limit of forced convection. I expect this to occur at a relatively normal wind speed. The geometry could be represented by a cylinder, with the wind direction perpendicular to the axis of the cylinder.
Mar 14, 2011 · RE: Heat transfer coefficient for Calcium Carbonate Scale ione (Mechanical) 15 Mar 11 07:16 Well the answer is it depends as scale thermal conductivity is related to its porosity and it is in the range 0.4 – 2.6 W/(mK).
Apr 23, 2022 · In heat transfer in a heat exchanger, conduction is a very small factor and is not even considered. The heat transfer coefficient contains all of the mportant factors. Conduction requires the thickness of the wall or the diameter of the flow channel to be the major factor, which you don't find in the equations.
Aug 3, 2006 · RE: Mean heat transfer coefficient for 304 stainless steel 25362 (Chemical) 3 Aug 06 16:12 Beside what BigInch tells you, kindly note that, except for the first units, your following units for the heat transfer coefficient are incorrect because they lack the time element.
Feb 10, 2015 · This was the issue that led to the argument between clean-dirty-service heat transfer rate. In summary, depending on the size of the plates the excess design and excess area will vary. For our case, it was found out that the overall heat transfer in service is similar to dirty and this is due to (what they say) to minimize excess area if the heat transfer rate in service is consider as a separate.
