сряда, 11 ноември 2015 г.

External combustion engine VS External combustion - internal cooling engine

Charts 1 and 2 depict external combustion engine, such as a free cooler imaginary (as in the familiar environment external combustion engine) closes the cycle. Accept that the 20% waste heat engines produced 100kW power for a given capacity of the converters of heat into mechanical energy (turbines, pistons in cylinders).

chart 1


chart 2

chart 3


chart 4


Charts 3 and 4 am figuring engines of the same capacity of the converters of heat into mechanical energy as chart 1 and 2, but here I have no imaginary "free" cooler. Close the cycle  by using force to close the cycle - cooling gas as  I use cooler - External combustion - internal cooling engines. Waste heat (20%) cooler return it in the evaporators of the unit. Accept that besides waste heat in evaporators returns heat equal to the force I used to close the cycle + 20%  of heat . So aggregates of diagrams 3 and 4 for the same capacity of the turbines will produce 40% less mechanical energy than units with imaginary "free cooling". If a  cooler is free - 100kW, and if  cooling is "paid" - 60 kW of power.
External combustion 100kW
External combustion - internal cooling - 60kW
for the same capacity of the turbine (piston / cylinder)

chart 5





chart 6


 On chart 5 am drawn external combustion engine with real free cooler - environment. On chart 6 - engine by method - external combustion - internal cooling, with the same parameters.
Assume - on 20% waste heat  - 100kW power of external combustion engine

Verdict:

1.On 20%  waste heat - 100kW  useful power of external combustion engine
   On 20%  waste heat -  60kW   useful power of external combustion - internal cooling engine for one and the same capacity of the turbines.

2.For the same capacity of the converters of heat into mechanical energy engine - external combustion - internal cooling gives 40% less mechanical power, but uses 40% less heat - no waste heat.

3. Another small deficiency on engine  by external combustion method - necessarily need heater to heat the hot part,  so that the engine to have a cold part. On the engine  by external combustion - internal cooling method the cold part we create it, so that we can use any heat, including of heater.

chart7



chart 8




Let's  take one external combustion engine as the  chart 2  filled with the same three working substances (ammonia, R41, R14) and go to Planet X, which has an atmosphere with a temperature of 130K - chart 7. Now, for such a unit will have free cooling, as we have in mind that the last working substance (R14) has a boiling point of 145K, and the atmosphere of Planet X on which the temperature is 130K. Light a burner and heat ammonia to 290K. I accept that for a 20% waste heat engine will gives  100kW mechanical energy.
Redesign the  External combustion engine to an External combustion- internal cooling by removing heat exchanger which cools the last working substance to liquefy in the atmosphere of the planet X - chart 8. Set in its place cooler loaded with nitrogen. Waste heat set it back into evaporators. As I said above, now I lose 40% of the power output of the unit, but also decreased  40% fuel in the burner.

On Planet X unit working with these substances can only work with heater, whether external combustion engine or an external combustion - internal cooling engine.

On Earth we do not need a heater - Sun heated the atmosphere at 290K and hence heat ammonia. But on Earth mandatory for these working substances  unit must be  performed by External combustion  - Internal cooling method, because no natural cold part.

Conclusions:

Engine - external combustion

1 With external combustion engine ever we need a heater.
2 In these units have free cooling 
3. We have waste heat

Engine - External combustion- internal cooling

1 Heater is not mandatory
2 For  the same capacity of converters of heat into mechanical energy (turbines; pistons / cylinders) has a lower power than external combustion engine
3 No waste heat

Summary of advantages and disadvantages of the method for converting heat into mechanical energy - External combustion - internal cooling

When using External combustion engine we pay for heating and cooling is free.
When using External combustion  - internal cooling engine is not required to pay for heating, but must pay for cooling.

 The price we play for cooling with internal cooling method is - less power for a given capacity of the converters of heat into mechanical energy (turbines; pistons/cylinders )


                        06 January 2016

I made some mistakes in the calculations for external combustion - internal cooling. True comparison between the two engines in the same capacity of the converters of heat into mechanical energy should look like:
At 100 kW  useful power and 20 kW waste heat

1. External combustion engine:
120 kW power of the heater
100 kW useful power
 20 kW waste heat

2.  External combustion -  internal cooling engine:

80 kW power from the heater 
80 kW useful force
 0 kW waste heat 
    20 kW from the gross mechanical power is converted into heat (so the net power becomes: 100-20 = 80 kW)
+  20 kW waste heat -  these two amounts of heat returned to the evaporator(s). This requires to reduce the power output of the heater wiht 40 kW : 120 - (20 + 20) = 80 kW 

It would be good to think about things in depth before presenting them to readers. I beg your pardon!

:) :) For my next invention I intend to never wrong :) :)

06 Jan 2016                
Svetozar the Cold

четвъртък, 5 ноември 2015 г.

Transferring heat from the cold to the warm part

Assuming that:
 1. For the liquefaction of a given quantity of gas by performing work on it, the amount of heat which will have received liquid substance is equal to the amount of heat the on gas plus heat equivalent of the work done on it  
2.The amount of heat which can be converted into mechanical energy of a liquid substance having a temperature higher than its boiling point is equivalent to a difference in temperature to its boiling point
3. The converter of heat into mechanical energy on the last cycle of the working substance in the "external combustion - internal cooling by more than one working substance" converted at less than 50% of the amount of heat
Then we will need to transfer waste heat from last cycle to previous cycles,  to enable the latter substance to cool the foregoing, and so the unit to work - diagram 1

diagram 1



Оn this diagram I chose option whereby heat of the last cycle is attributed to the liquefied gases the last working substance and on the evaporator of the previous working substance, but it can distribute heat to all evaporators of the unit.
Comparing the amount of heat and temperature differences of useful and opposite force - the unit would be effective. 
Because of the heat that will bring in the evaporators on preceding substances will allow to reduce the flow of pumps -the amount of circulation of the relevant working substance.

diagram 2



In method of heat exchange between liquid and gaseous working substance is not  necessarily the last evaporator (n on diagram 2) to be at low temperature. We can have an effective unit in which gases from all evaporators enters the cooler, which returns heat in the evaporator n  . His temperature will not be the lowest in the unit, but the  useful forces are bigger than the opposite and this option.

понеделник, 2 ноември 2015 г.

Option to transfer waste heat of the last cycle to previous cycles (puzzle)

On unit filled with more than one working substance can transfer part of the waste heat of the last cycle to the previous working cycles of substances with a higher boiling point. In each evaporator place warm heat exchanger on cooler. Adjustable valves are adjusted so that the working substance of the cooler to give heat on the working substance of the respective evaporator. By valves can choose to transfer heat to one or more evaporators (in the case of diagram 1  waste heat  from the last cycle transfer to the previous cycle, but I can configure the system to transfer heat to all evaporators which has a unit).

diagram 1


Wout / Win = ?

diagram 2




Water cooled propylene glycol, and carbon dioxide cooled all (we are used to associate it with increasing temperature, but I intend to entrust it the task to cool) as transfer waste heat from the last working substance to the previous two.
Wout / Win = ?