When one energy is converted into another energy then some parts of the energy is lost during conversion and after this the required energy that is achieved is its efficiency. The formula of efficiency is about

According to the given situation in the figure the efficiency of the system will be about

According to the point 1 the system will work in clockwise direction.

At the point 1 there is heat source and it is also an energy source and acting like an input. It is measured in joules.

The next point is related to the energy that is lost during conversion  and it is measured in joules.

After this, the next point is the output of the model of the system. At this point the energy is transferred at the user end and this is the output of the model and it is represented as . This is also a form of energy and it is measured in joules.

In the point 4 the heat energy that is lost is moved towards the source again, and it is measured in joules

The last point is related to the heat energy that is moved back towards the source. This can be done through the help of water pump and in that pump work has been done and it is also measured in joules  

Question 2

For measuring the efficiency of the heat and the heat that is lost during transferring and the heat that is gained and moved towards the source.

Heat measurement

 This heat can be measured through the help of thermocouple. It is a heat measuring device, this device is able to measure the heat through the potential difference between two wires. Then this value is compared with the thermocouple table and results are evaluated.  This device is one of the simplest one for measuring the temperature. Always give correct information about the temperature. Cheap device to measure the temperature. The measuring method is difficult and it takes time, but for the experimental proposes this device is useful.

Pressure measurement

For measuring the pressure Bourdon tube gauge is used. It contains a bent tube inside it and it became straighten when there is increase in pressure. This device is cheap, easy to use and it is also sensitive The pressure measuring accuracy is low but it can be used for experimental purposes. It is an analogue device for measuring pressure

Measurement of fluid flow

For measuring the fluid the positive displacement meter is used. The value is accurate and it is about 0.5% for the liquid and 1.5 for gases, easy to use, gives analogue value, Accuracy is extremely low. Measurement range is low but can be used for the experimental purposes.

This experimental system is also storing the data from the heat sensor and transfer it to the computer system. This system can be operated through the help of remote controller.

Question 3

According to the information the system is steady state so the potential energy can be neglected. These equations are totally based on the points that are discussed in the question 1.

The numerical inputs came from the source of the system, for assuming this lets consider the input stage is at steady state position

The heat capacitance can be measured through

The equation for water pump, the height of this pump is constant, the numerical input for the water pump come from the heat energy that is gained before the pump. For the equation for the water pump, let consider the value of this pump will be come from the Bernoulli’s equation.

For the ideal water pump

The efficiency of the complete system will be

The energy balance equation of the system will be like that

The equation will be in the form of

Question 5

There are about 12 factors that are affecting the efficiency of the district heat system

1)      The design of the experimental system

2)      The design of the water pump

3)      The heat source

4)      The energy that is lost during transferring

5)      The length of the return pipe

6)      The length of the supply pipe

7)      The efficiency of the water pump

8)      Power of the water pump

9)      The torque pattern of the water pump

10)  The coating of the pipes

11)  The output temperature of the system

12)  The environment of the system

Question 6

These factors are categorized into two groups the first one is related to the high impact factors and the next one is related to the low impact factor

High impact factors

1.      The design of the experimental system; The reason is that if the design of the system is not accurate then it will be extremely difficult to get absolute efficiency of the system

2.      The length of the supply pipe; the reason is that if the length of this pipe is not accurate then right amount of heat is not transferred at the output end.

3.      The length of the return pipe; this is another high impact factor because due to this the energy is lost at high rate and proper efficiency can’t be measured properly.

4.      The coating of the pipe; this is also high factor because due to this proper heat is not able to be transferred at the output end.

5.      The power of the water pump, if this power is low then proper heat is not easily transferred.

6.      The heat source: if the heat source is weak then the efficiency of the pump is affected badly

Low impact factor

A.    The design of the water pump; the reason is that if the design is not perfect but there is no huge impact on the efficiency

B.     The energy that is lost during transferring; this is also low because energy always loss during conversion

C.     The efficiency of the water pump; this factor has low effect on the system because it only depends upon the power of the pump

D.    The torque pattern of the water pump: if the torque pattern is bad then there is little effect on the efficiency of the system

E.     The output temperature of the system; the output temperature is effecting during measurement only

F.      The environment of the system; the environment also effect during measurement of the efficiency

Question 7