Cooling Definition and 646 Threads

Hi everybody! I'm currently working on a project where a wet cooling tower is involved. The wet cooling tower is an induced draft system. I know the volume of air handled and also the properties of the air entering and leaving the system. I want to determine the electricity consumption of...

If the hood of my at rest car is 106 degrees and I drive at 55 MPH, how much is the hood temparature reduced by the wind so created?

Homework Statement Hello guys, I'm stuck on a problem I've met in an exam and that I will roughly copy out of memory. There was a substance that had a transition to liquid helium at ##T_0=3##K. Also, ##M=\frac{nDB}{T}## (Curie's law was satisfied). Specific heat at constant magnetization was...

Here is the question: I have posted a link there to this topic so the OP can find my work.

Humidity is known as mass of water vapor/mass of dry air Hs (saturation) = (Mw/Ma){Ps/(P-Ps)} P is total pressure Ps is saturation pressure what is the derivation for this equation?

Here is the question: I have posted a link there to this topic so the OP can see my work.

Homework Statement In autumn 2011 a whale was stranded. Although the whale was already dead for some time and the ambient temperature is approximately constant at the freezing point was, the body temperature was inside lying on the beach of Wales on 21 November is still about 20 ° C...

Hi everybody, I don't know if we have any computer people on here, but I've noticed that even when it's not covered up, my laptop has been getting a lot warmer than normal and the fan kicks on much more frequently. I know its unhealthy for it to get hot and was wondering if anyone had any...

Homework Statement A hot body placed in the surrounding of temperature θo obeys Newton's law of cooling dθ/dt = -k(θ-θo), where k is any constant. Its temperature is θ1 at t=0. t is time. The specific heat capacity of body is "s" and its mass is "m". Find the time starting from t=0 in which...

I have a book called REA 's problem solvers: Differential Equations Year 2004 and the problem 12-14 on page 244 might have problems with it and I want to ask to see if anyone else thinks so. The problem is basically Newton's cooling where they ask to find T - T_o = (T_i - T_o) e^(-kt)...

Dear all! Somebody, please tell me which crystal is soluble in hot water but not in cold water. I am looking for some crystalline chemicals which are strong enough to bind something like glass beads. As I mentioned, it should be highly soluble in hot water (or change into liquid on high...

While reading up the recent hoopla about DWave's new "Quantum Computer" I came across a practical question about cryogenics: How long could you keep a 10 kg mass at below 80mK without any external cooling if you could design the best practical insulation system? DWave claims it is "several...

I am working on a concentrated solar heater using a linear fresnel reflector. I want to learn how I can harness this heat to power a cooling system, preferably with minimal use of electricity. I am in India, so this has a huge ground for application. I was looking at ideas here, and while...

Relation between Cooling rate and Viscosity Hi all I have a situation where i have a molten Aluminium Copper alloy melt poured in a mould to be solidified. This means, the mould temperature is lower than than than the poured melt. I am thinking about a relation which associates temperature...

What is exactly the control system employed for forced cooling of transformer? 'If the load on transformer increases,then temperature rises & the mass flow rate of coolant has to be increased' is it true? So is there any sensor/transducer for sensing (taking the feedback) of flow rate of...

i mean to say how does this method extract energy, I've read the wiki but in my head it seems as though you can only extract as much energy you put in and why can't we use this to get to absolute zero?

Hi This is just a quick question, it should have a pretty simple answer however I can't find the information anywhere on the internet. When you are calculating/estimating the heat transfer coefficient for a prismatic fin using the reynolds, prandtl, grashof, and nusselt number, what length do...

Remembering 10 years ago ish, hearing about a plan in Norway using a mirror in space to reflects light into the North Pole. I am not if they have done it or not but here is the deal, Earth is in space (which is at around Absolute zero) how long it takes for the Earth to freeze if light of sun...

where can I find the" cooling tower institute blue book" soft copy Hey I'm doing a university project on cooling towers .The cooling tower institute published certain curves [cooling tower characteristic curves ] that I need on the "cooling tower institute blue book". There is also have a...

Hi guys, I'm designing a cooling device as part of a project and need a little help with the maths. OK, so the scenario is this, take boiling water, put it in a stainless steel container with Thermal Conductivity of 8.7 Btu/h ft °F and dimensions of 15.811cm x 15.811cm x 1 cm to store 250ml...

Homework Statement A steel cylinder of diameter 8cm and length 12cm is initially at 600°C. It is placed in oil at 20°C for rapid cooling, for case hardening of the surface layer. The value of h is 60W/m2 K. Use the numerical method. a. Determine the time in which the maximum internal...

I have a set up which is basically a small wind tunnel (single rectangular channel) with an axial fan at the inlet. The experiment is testing the effect of various shaped "shrouds" that constrict flow around an inductor to improve the convective cooling. I have heat transfer coefficients and...

I'd like to know the dimensionless parameters affecting a counter-flow induced draft cooling tower's performance, or if someone could direct me to an adequate resource . I'd also appreciate if I could be directed to some good comprehensive resources on cooling tower design Thanks guys

A friend and I got into a debate regarding the characteristics desired in a gas for forced air cooling. Having worked with mass flow meters, I was well away of how hydrogen and helium had high thermal conductivity. However, as my friend pointed out, simply having high conductivity (i.e. a...

hi all. i am trying to formulate some testing of different motor oils. i am looking to document which oils have better cooling properties. i read some info years back that a straight oil like SAE30 actually cools better than say a 5w30, reason being is because the multi-grade uses long chained...

Homework Statement Hi! I need some help by my phisycs homework at universty. Here is the problem: We have a steel ball, with density of 7800kg/m^3, with speficic heat capacity 460J/kgK. Temperature of the ball is 1700K. How much time does the ball need to cool down to half of it's temperature...

Newton's law of cooling says: Instantaneous rate of cooling = -k (Original temperature - Final temperature) But what does this 'k' mean? I know it depends on the nature of the surface; but what property does it correspond to? Is 'k' related to specific heat capacity? Does higher...

Hi all, I am not clear with the concept of "Cooling" a body.I know that the temperature of a body is the average kinetic energy of the molecules or atoms in the body.When heat energy is supplied,the molecules have more vibrations and hence the temperature increases.Let us have two bodies at...

Hi Can anyone surmise the advantages and disadvantages of ultra low below 1K cooling methods: cryostat cooling (HE3) as compared to Nuclear diamagnetisation

if you hold a pitcher of water under sun you sea cooling of water in it, you transfer heat from hot to cool without do work, how do you explain it according with second law of thermodynamics?

Newton's law of cooking T(t)= Ta+(To-Ta ) e^(-kt) or search it up online for a cleaner formula. Anyways, what does the cooling constant k represent. What do larger or smaller values of k mean? Thanks

It is commonly said (based on a quick Google search) that wrapping your beer in a wet paper towel and placing it in the freezer will allow it to cool faster than placing it in the freezer without said paper towel. Newton's Law of Cooling suggests otherwise. The fact that water releases energy...

I have a steel block (2.75m x 1.6m x 0.5m) sat at 1000°C in ambient air (22°C) How long will it take for a surface to drop to say 800°C should i use the heat transfer eq: Q=KA\DeltaT to find the power in joules per second, then transpose to find seconds somehow? Any help will be...

I have a automatic air pump like this one(http://www.thatpetplace.com/silent-air-x-5-air-pump-80-gal-2-outlets) and pass it through a metal pipe, while the metal pipe is cooling at 32 degrees and the air within the pipe cools and goes somewhere and then that same pipe(no breaks anywhere) loops...

I have a pipe that needs to be 5 degrees below the external temperature outside(eg- 45 degrees outside means 40 degrees within). I cannot remove the pipe or anything, all I can change is the what the pipe passes through, for example if it passes a block of ice then technically the pipe would...

Hi, I have a problem with measuring cooling performance of a car on a chassis dynamometer. But maybe I should start with the theoretical part of my problem, namely with the dimensional analysis. If I have a physical system and I am interested in finding one variable as a function of all other...

I have a couple of questions regarding laser cooling. I should preface this by saying that I've taken a course in Modern Physics, so I don't have more than a very basic understanding of QM. In this case, I am familiar with absorption/emission lines, Zeeman effect, degeneracy and quantum numbers...

I have a couple of questions regarding laser cooling. I should preface this by saying that I've taken a course in Modern Physics, so I don't have more than a very basic understanding of QM. In this case, I am familiar with absorption/emission lines, Zeeman effect, degeneracy and quantum...

Homework Statement An electronic chip of 5cm x 5cm surface is to be cooled by a water cooling method (see drawing) Homework Equations If 500W of heat is to be removed from the chip, what is the temperature of water from the time of operation until 5 hours if the fan is not operational...

I am trying to find out as many ways of cooling down matter as possible and information on said ways, so far I have found out a bit about laser cooling, evaporative cooling and that's about it. I'm sure there are other ways but I can't find any and the information I can find on these ways is...

Hey all, I was wondering if someone could explain the difference between isothermal and adiabatic processes. I know that in isothermal process, there is no temperature change in the system, and in adiabatic process, there is no heat transfer. However, can someone explain to me what each one is...

Hello. I need to estimate height and diameter of a cooling tower. My water requirements are 50000 m3/h, for a cooling duty of about 730 000 000 kcal/h. For this capacity, I thought that an hyperbolic tower, natural draft, would be the best choice. Am I right? Water temperatures in-out would...

What experiments have been conducted to confirm that the Cosmic Background Radiation (CBR) is indeed cooling over time and at any specified rate? The time requirement for obtaining separate points for measuring change seems preclusive.

I have to present an investigation on a topic that is related to healing and cooling. In class we're studying kinetic theory, ideal gas laws, heat, temperature, specific capacity, change of state, boiling and evaporation, energy conservation and degradation, and the transfer of heat. Are...

I'm really not sure, have I gone through the right process here? I didn't actually finish the calculation, I'm just curious about the process.

A certain part of a closed loop cooling water systmem has to have some of the pipes made to have a larger diameter to allow more flow. Does this mean though that the overall pressure in the system will drop? I know the headloss in the widened pipe will decrease and flow increase. But will you...

Homework Statement Captain Ralph is in trouble near the sunny side of Mercury. The temperature of the ship's hull when he is at location (x; y; z) will be given by T=e^(-x²-2y²-3z²). He is currently at (1,1,1). a)In which direction should Ralph go to cool the fastest? b) If the ship can...

I attached the HW assignment. Its question number 2. I choose a control volume including the cooling stream from the lake and the fluid being condensed. I assumed with this CV that the heat generated was 0 and that the net Work was 0. Using these assumptions I solved for the mass...

Superheated H20 at 400 kPa is slowly cooled in a sealed rigid vessel until the temperature is measured to be 115 centigrade, when condensation first occurs. What is the Initial Temperature? I know that the temperature and pressure at point two (saturated vapor) can be found in a standard...

As an amateur astronomer I want my primary mirror (diameter 37 cm) to maintain the same temperature as the air. Small fans on the backside do the job. Only, the air cools quicker during the night than the 1.5 cm thick glass. Do I obtain a slightly lower temperature on the backside by sticking...