Cooling Definition and 628 Threads

Hello Everyone, I am Mayur I am working on a system, in the system there is one diffuser through which exhaust gases at 3000K are flowing at a rate of 170Kg/s. The material of diffuser is Stainless Steel. The diffuser is double walled type with cooling water flowing between the walls. I need...

Homework Statement A hot metal rod is placed in a water bath whose temperature is 40F. The rod cools from 300F to 200F in 1 minute. How long will it take for the rod to cool to 150F? Homework Equations The Attempt at a Solution I know y'=-k(y-T0) and y(t) = T0 + Ce^-kt and i...

ok racers, here is a subject I have been debating. our formula car uses two aluminum radiators, one on each side. I switched to the Ultra Side pods which are each 5 pounds lighter and 3 inches narrower than the original sets. Benefit is lighter weight and lower aero drag. now the questions, 1...

Advice needed please with the design of cooling vents, louvres on the cowling of a radial engine. Plane is a Sukhoi, as per vid links below, 76 inch span 37cc petrol engined radio control. Cooling will be from cutouts in the cowl approx 20 x 80 mm with a flat plate louvre at the leading edge...

Hi, I'm a cyclist who has just got some rollers, which allow me to ride inside without going anywhere - essential if I want to ride on harsh winter days. The problem is, without the cooling airflow normally experienced when out on the road, heat exhaustion makes long periods of indoor training...

Hi there, my first post on this forum and I hope its in the right place ! My question is this, in an exisitng air-cooled motorcycle engine what is the viability of using heat pipe technology to cool exhaust gas temperature? Using heat pipes to remove heat from exhaust valve areas to external...

Homework Statement Hi, I need some help in solving Newton's law of cooling problem. Use Newton’s law of cooling to determine the reading on a thermometer 5 min after it is taken from an oven at 72 ◦ C to the outdoors where the temperature is 20 ◦ C, if the reading dropped to 48 ◦ C after...

If we were able to build a gas core reactor, how much heat would need to be dissapated? I bring this up because traditional solid core reactors require lots of heat to be pumped away (do you know the exact number?) to keep the core for melting, but since a gas core is already much hotter...

Hi guys and gals :smile: I am currently working on a project that involves server cooling. My objective is to make some sort of (gross) generalization about what kind/size fans go into typical rack mounted servers. When all is said and done I would like to be able to categorize my findings in...

Homework Statement Suppose that a cup of hot coffee at a temperature of 1850 is set down to cool in a room where the temperature is kept at 700. What is the temperature of the coffee 10 minutes later? Homework Equations f(t)=(T0 - T1))e-kt + T1 where T0 is the initial temperature of the...

Homework Statement a body has temperature 27C at twelve oclock. The room temperature is constant at 16C. Two hours later the body was found to have a temperature of 24C. The temperature of a normal human body is 37C.Using Newton's law of cooling estimate the time of death. Homework...

I'm going to write this up the same way my teacher gave me the sheet Homework Statement At 9am on october 19, 2009 a body was found in room 327 at University Center. The room is kept at a constant temperature of 72 degrees. The medical examiner was called and he arrived in eight minutes...

I'm going to write this up the same way my teacher gave me the sheet Homework Statement At 9am on october 19, 2009 a body was found in room 327 at University Center. The room is kept at a constant temperature of 72 degrees. The medical examiner was called and he arrived in eight minutes...

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Hello all, I am doing a research which involves hollow copper conductors. I would like to know about some kind of coolant or gas (like SF6) which can be passed through the copper tube to cool it, the temperature of the copper conductor can reach upto 100 degree C. The coolant should cool the...

Hello all, I am doing a research which involves hollow copper conductors. I would like to know about some kind of coolant or gas (like SF6) which can be passed through the copper tube to cool it, the temperature of the copper conductor can reach upto 100 degree C. The coolant should...

Hi. I'm trying to apply Newton's cooling equation (if relevent) to the following system. We produce plastic piping, extruded at about 200 'C and cooled via water sprays to 35 'C. We are trying to calculate how fast we can run the pipe through the cooling sprays. It's been a very long time since...

Could I get a hundred feet of 3" corrugated drain pipe for the air and run it through a 6" corrugated drain pipe for running cooled evaporated water which would be pumped out of one end and gravity fed through the other end. As for the air "tube", I would run one end into the home at one...

Homework Statement The temperature, H, in degrees Celsius, of a hot cup of coffee placed on the kitchen counter is given by H=f(t), where t is in minutes since the coffee was put on the counter. Is f'(t) positive or negative? What are the units of f'(20)? What is its practical...

Homework Statement I have two problems. What is Delta U, Delta H, q, and w for the Reversible heating of an ideal gas at constant P. Also, what are these values for the Reversible cooling of an ideal gas at constant V. Homework Equations The Attempt at a Solution For the...

I am trying to solve an advanced heat transfer problem and I have a 2nd order ODE. I can solve the homogeneous solution easily, but I am having trouble with the non-homogeneous solution.Homework Statement Given a turbine blade and asked to model as a one-dimensional fin, subject to the...

Hi everyone, I have encountered a situation described as follows in my research and would appreciate it if someone could help me out - A ball of metal vapors ( Pressure = 10^10 Pa and T = 10^4 K) is suddenly exposed to He gas at 1 atm. I wanted to know how would the Temperature change due to...

Homework Statement A thermometer reading 70o F is placed in an oven preheated to a constant temperature. Through a glass window in the over door, an observer records that the thermometer reads 110o F after 1/2 minute and 145o F after 1 minute. How hot is the oven.Homework Equations...

http://www.ucar.edu/news/releases/2009/arctic2k.jsp The associated albedo flip will amplify the warming.

the diesel cooling engines as produced by deutz have huge fans to deliver substantial amounts of air to the engine. they draw a lot of power from the engine. is it possible to use a mesh of delaval valves like a radiator that drops the temperature of passing air, thus, reducing the amount of air...

Hi, in a lecture I was told that the cooling of neutron stars cannot happen via the 'direct' Urca process (beta decay and inverse beta decay), because the created particles cannot go into occupied states (Pauli exclusion). The 'modified' Urca process was introduced, with an additional neutron...

Homework Statement You are given 2.5 102 g of coffee (same specific heat as water) at 70.0°C. In order to cool this to 60.0°C, how much ice (at 0.0°C) must be added? Neglect heat content of the cup and heat exchanges with the surroundings. Homework Equations Q=(m ice)(c ice)(delta T...

I have a dough passing through a pair of rollers equipped with internal circulating chilled water. given: mass flow rate, specific heat and temp in/out of the product diameter of the rollers, its material. temp. in of the chilled water. problem: cooling load needed for the chiller.

I would like to determine how long it would take a volume of water to cool from an initial temperature to a final temperature in a given ambient temperature. I don't know the volume, is this information important? If so, is there any way to come up with the time it would take as a function of...

I have experimented the converse of Newton's law of cooling, i.e. the rate of heating of a cold body is directly proportional to the deficient temperature when the difference in temperatures is small and the states of the system remain the same.

Suppose the temperature in your room is 25 °C with 100% humidity. You are feeling very hot and sweating a lot. Most of the sweat does not evaporate on your body, it just drips onto the ground. If you switch on the heating in your room, would you feel more comnfortable? It seems to me that by...

Fusion raction produces high energy neutrons which cause activation of the walls of the reactor. Why can't their energy be collected by, for example, a microwave beam?

How much electricity does it take to liquify oxygen? I am just curious as if it only took small amounts one could create a power plant that liquified oxygen, put it in a small chamber outside to return it to a gas and used the pressure to turn a turbine with the gas returning for cooling. This...

Hello everyone :smile: I'm just wondering why is cooling considered to slow reactions. I mean f you want condensation heating would slow the reaction. I like to know exactly how condensation occur at molecular level. I know when you heat gas it expands. So when you cool a gas does it...

Is there a PDE describing temperature as a function of time for a sphere in a vacuum (a moon in space)? Since it can only radiate, the boundary would be a function of temperature to the fourth power (nonlinear), right? Is there a book or thread out there I can reference? Maybe this can...

I'm unsure how to approach this, as solid blocks of materials next to each other (e.g. steel and air) with no barrier inbetween as shown on http://en.wikipedia.org/wiki/Thermal_conductivity "x" would equal zero, this can't be correct. Is there another equation relating temperature difference...

The degrees of freedom associated with the possible orientations of the spins of the magnetic atoms constitute a spin system, which is in thermal interaction with the degrees of freedom of translational motion of all the atoms which constitute the lattice system. If the external magnetic...

Newton's Law of Cooling Time Required to Cool (or heat) an Object [Also known as Newton's Law of Cooling] t=mCp(Ts-Tf)/Q Where; Q is the heat added (or being removed) from the object in watts m is the mass (weight) of the object in Kg Cp is the Specific heat of the object...

Homework Statement The temperature T of a cup of coffee is a function T(t) where t is the time in minutes. The room temperature is 20 ^\circ Celsius. The rate at which the coffee cools down is proportional to the difference between the temperature of the coffee and the room temperature. Use...

I wish to know more about the latest laser cooling techniques. I have heard about the use of radio waves to cool the laser. Can anyone throw more light upon it? Is there any latest technique in use these days to cool Nd:YAG laser ?

Hi there, I need to prove to an architect that the most economical and efficient way to cool our server room will be with an Airconditioner. At present we have a system which is supposed to recycle the warm air downstairs suring winter and Outside during summer, only it doesn't draw nearly...

Ok so my question is about hot water in a home Lets say that I take a shower a shower and i use 20 gallons of water at 105* F If the hot water in my tank is at 140*F and my cold water comes in at 50*F how much of hot (140*F) water did i use? How much cold (50*F) Water did i use? Now...

Approx. 14,000 years ago, a large percentage of the globe was covered in ice. Estimates vary from one third to one half of the globe covered. This was the result of a several thousand year build-up. The passing of each winter/century/decade/millenium, would have seen an increase in the ice cover...

I wanted to ask which would provide the largest total BTU cooling regular ice from water or dry ice to reach a temperature of 25 degrees C? 1 lb of Ice would start at -3 degrees C to 25 degrees C at sea level = total BTU 1 lb of Dry ice would start at -80 degrees C to 25 degrees C at sea...

If I have a spherical container with volume 10 in^3 filled with air at 1000 F and 100 psi pressure and the container is thermally insulated, how much water (initial T=10 F) I need to inject inside this container to reduce the temperature to 500 F? What would the final pressure inside the...

Homework Statement Ok, I am designing a brake system for a uni project, as part of this i need to specify the size of the disc's, to prevent the brake fluid from boiling during braking. Does anyone know of an arbitary formula which will help me calculate the rate of heat loss from the...

a cup of coffee is heated to 100° then left in a room with a constant temperature of 68° after a minute the temperature of the coffee has dropped to 95° after another minute to 92 degrees. how much time must pass before the temperature of the coffee has dropped to 70°?

I'm on the lookout for a website dealing with calculation of cooling effects in deep freezers (for food storage and such). The main goal for me is to learn the basics of how to find the needed cooling effect from input values like amount of food, required temperature, room size, insulation, etc...

I understand that adiabatic cooling is the reason as to why, a valve releasing compressed air from a tire, would become cold. But I'm having a hard time grasping why this actually happens. I've been searching online, and I can't seem to find the type of simplified answer I'm looking for...

Homework Statement a) An object at 200 degrees F is put in a room at 60 degrees F.The temperature of the room decreases at the constant rate of 1 degree every 10 minutes. The body cools to 120 degrees F in 30 minutes. How long will it take for the body to cool to 90 degrees F? b) Show that...