Mechanical Engineering

• entries
366
1,425
• views
868,100

# What is the Difference between 'Thermodynamics and Heat Transfer'?

35,346 views

What is the Difference between 'Thermodynamics and Heat Transfer'?

(Question given by Ayesha)

1. You can answer this question

2. You can like the best answer

3. You can share the question..

thermodynamics is defines the relation between heat and temperature with energy and work in a system. its also a large scale analysis. also its is not counting the heat transfer rate

heat transfer determines the heat transfer from a system to the surroundings though the conduction, convection and radiation modes of heat transfer. this is also helps to identify and reduce energy lose through heat energy

HT(Heat Transfer)=TD(Thermodynamics)+FM(Fluid mechanics)+MSM (material science & metallurgy)

Thermodynamics deal with the total energy transfer to/from the system without considering the time frame, while heat transfer deals with the rate of the transfer and relative time brings in the picture the study of heat transfer.

Thermodynamics is the discription of state of the temperature between two points while heat transfer deals with the temperature varieance of the whole body being considered .

we know from our expeirence these tempratures difference are reduce in magnitude in the course of time by heat flowing from region in high temperature to region in low temperature. the body in consntration maybe in the solid status it maybe a liquid or it maybe in gases status does not matter with statu it, the point it is  when temp is different we know the heat flowing from high temp to low tempe.

So the subject dealing with the rate at which heat flow process occurs is called heat transfer.

in thermodynamic normally when we have system in circumstance and that system under goes heat in the working direction because of those heat working direction the system goes from one equilibrium statu to other equilibrium statu  and during that shift from one to other equilibrium statu  because the heat working direction the system goes at end circumstance which describe by pressur, tempe etc.

now in thermodynamic we have generally asking the question how much time goes that process , we never consider the rate at which the heat flowing takes place.

and the otherhand heat transfer we said because temp is diffr heat flow occurs , what is the rate at which the flow is occurs and at thermodynamic how much time?

Thermo=heat

Dynamics=motion

Thermodynamics only determines the starting & ending state of heat

Heat transfer takes place through conduction ,convection ,radiation.heat transfer determines heat at any point in the system where thermodynamics process takes place.

in heat transfer, we study about process of transferring heat from one body to an other body like conduction ,convection & radiation

but in thermodynamics we study about the effects of transferring heat on body

like internal energy , entropy, enthalpy

In thermodynamics we assume bodies at static equilibrium and in HT we focus on Rate of Heat transfer that takes place through a body

"Thermodynamics" deals with the amount of energy in form of heat or work during a process and only considers the end states in equilibrium.Heat transfer deals with rate of energy transfer.

Heat transfer is related to time variation ie, properties must be analysed on time basis.Thermodynamics deals with only equilibrium conditions.

Thermodynamics is about the dynamics within the heat (work-energy conversion, entropy, etc) where as heat transfer is about the dynamics of transfer of heat(conduction, convection, radiation

THERMODYNAMICS  EXPRESSES THE CHARACTERISTICS OF HEAT,MASS,SOLIDS, LIQUIDS, VAPOUR AND PHASE TRANSFORMATIONS AND ITS  RELATIONSHIP AND USE OF WORK,ENERGY AND POWER IN STUDY AND IN MOTION.

heat transfer determines the heat transfer from a system to the surroundings though the conduction, convection and radiation modes of heat transfer. this is also helps to identify and reduce energy lose through heat energy

THERMODYNAMICS

in thermodynamics; certain equilibrium state of the system and that system undergoing certain heat or work interaction the system goes from current equilibrium state to another equilibrium  state and this is describe by temperature, pressure etc.

now in this process we are not asking the question how much time goes in that process also we never concern ourselves with the rate at which that heat interaction takes place.

on the other hand

in HEAT TRANSFER

we ask rate of heat transfer because there is a temperature difference heat flow occurs; what is the rate at which this heat flow occurs?

And at a certain point if we want only certain temperature to be attained,how much time would it take-that is the type of questions ask in heat transfer,it is necessary because in study of heat transfer some laws that governs the process of heat transfer on the basis of this rate design equipment ,size equipment in which heat transfer process occurs.

Thermodynamics is branch of science that deals with the system in equilibrium states only,ie how much heat is transfered from one equilibrium state to another equilibrium state but heat trasfer tells us the rate with which heat is transfered,either in equilibrium or not.So this the reason unit of heat in thermo is joule but in heat transfer it is watt(j/s)

Here is the basic difference.

Thermodynamics is continuing heat transfer

And heat transfer is transport a heat from a point to z point

heat transfer  tells about rate .but thermodynamics didnot  tell about  . in thermodynamics we get  the amount of  work  but we fail to get how much amount of time to get  to complete that work .  heat transfer  tells   amount of time. how much time to get for complete  work.

Thermodynamics mainly depends upon  law of conservation of energy and mass , it depicts temperature, velocity, mass, volume etc., it gives heat to the system and get work from the system  (e.g) HEAT PUMP

Heat transfer depends transfer of energy or mass it occurs three modes conduction, convection, radiation Best example of heat transfer (i.e) HEAT EXCHANGER UNDER CONVECTION

HT deal with Time but Td not

×   Pasted as rich text.   Paste as plain text instead

Only 75 emoji are allowed.

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×