Temperature gradient Definition and 20 Threads

I'm trying to find a heat transfer equation that includes time. Metal tank, partially filled with liquid. I need to find the time it would take for the temperature on the outside of the tank to drop from θ2 to θ1, given thickness, metal and liquid's properties, and tank dimensions

Hello all, It seems like a fairly straightforward question but I cannot find any information in the literature. Let's suppose we apply a crack driving force K1=45 MPa.m^0.5 to a notched specimen with an upper shelf fracture toughness K_mat = 50 MPa.m^0.5 at room temperature T0=20 oC. Under a...

I have a pipe holding liquid at 80°C. The outside atmosphere is -2°C. The pipe gets a temperature gradient over the wall thickness. The outside fibers will thus restrain the inner fibers from expanding. I would like to know the increase in the inner dia of the pipe. I have found temperature...

I've seen a bit of research that relies on imaging methods like FLIR for input. My question adds a couple wrinkles: How could a robot Navigate without imaging? I.e., using only local sensors like a thermocouple or array of thermocouples. Extract navigation info from turbulent thermally...

what does the relation between the temperature gradient inside the thermal boundary and thermal boundary layer thickness i mean what will be the temperature gradient ( high or low) when the thermal boundary layer is thick relative to the thin one? Kindly explain mathematically and physically as...

Homework Statement Hello everyone, I hope that you guys could lend me a hand. I need to calculate the heat loss at any point over a long pipe while considering lambda of the pipe. I am trying to use octave to find a reasonable flow-rate to keep the temperature loss to a minimum at a reasonable...

Homework Statement To derive a formula to find the angle of twist when a torque T is applied and the temperature gradient is ΔT Homework EquationsThe Attempt at a Solution Angle of twist Φ=TL/JG I believe as temperature decreases, torque will increase which means angle of twist is inversely...

I just did a thermoelectric generator from seebeck plate. And when temperature increases, the plate's resistance increases from 12 ohms to 8 M ohms. Why is that and how todeal with it??

Hello, I have been playing around with a simulation software package and ran a heat transfer simulation however, to me the results did not seem intuitive. From my understanding the distance heat travels in a specific amount of time is proportional to the temperature difference, for example...

Hello, I am new here and took a look through the forms, if there is a better place for this question, feel free to move it there. I have been busting my noggin trying to google the answer to this problem I have. (Which isn't school/homework related) I am looking to determine an approximate...

Hello everyone, So I am an Aero-Thermo Intern at Pratt and Whitney, and my supervisor gave me the following problem to set up a mathematical Excel model for the temperature gradient inside an enclosed box with a heat source underneath it to be used in thermal analysis of an engine component...

Anyone know how to use the temperature gradient in a thick-walled tube to calculate the stress seen throughout the wall (radial stress gradient)? I've been scouring the internet for a good explanation but haven't found one.

Assuming that the accretion disk has been totally consumed by the black hole, does the temperature of the black hole due to Hawking radiation vary with respect with proximity with the black hole? For example, if I were next to the black hole, would this radiation would have a higher temperature...

Hi, could you please help me with my homework? I want to determine the height of mountain (from foot to peak) using the speed of sound. Homework Statement Known data: time delay, height1, temp1 plus known dependence between the height and temperature. What I want to determine: height2...

Hi folks! I was wondering if anyone can help me with a problem I'm having with the concept of thermocouples. If I understand correctly, there should necessarily exist a temperature GRADIENT in one of the conductive couples in order for the emf to be generated. So how can you make sure...

Hello again folks :smile: This thread is regarding the Finite difference scheme for a 1-dimensional Heat transfer problem with non-uniform cross-sectional area. As seen in https://www.physicsforums.com/showthread.php?t=397891", when the element has constant cross-sectional area, things...

URGENT: Heat transfer - temperature gradient value at a certain point Homework Statement Given a very long cylinder of inner R1 = 0,01 m, outer radius R2 = 0,1 m, that transports water at 150ºC, and surrounded by air at 25ºC, find the temperature gradient value at R = 0,07m. \lambda = 500...

Hi, Say I have a sphere of radius r that has a constant surface temperature of T_s. The sphere is surrounded by air at a constant temperature T_amb. I am interested in the temperature gradient surrounding the sphere. From the little I know, I think i have to look at the natural...

Is there a direction A in which the rate of change of the temperature function T(x,y,x)=2xy - yz at P(1,-1,1) is -3ºC/ft? Give reasons for your answer. For this problem I found the gradient of at the point P. So \nabla f = 2y|_p \mathbf{i} + 2x-z|_p \mathbf{j} - y|_p \mathbf{k} which I...

Hi, can someone please explain to me what is meant by a temperature gradient in the context of thermodynamics? Something I've been reading goes along the lines of "...To reverse the direction of conduction would require a reversal of the temperature gradient in the conductor. Thermal conduction...