WO2019009866A1

WO2019009866A1 - Cooling/air conditioning system with liquefied gases

Info

Publication number: WO2019009866A1
Application number: PCT/TR2018/050338
Authority: WO
Inventors: Rahman ŞİMŞEK
Original assignee: Simsek Rahman
Priority date: 2017-07-04
Filing date: 2018-07-02
Publication date: 2019-01-10

Abstract

Invention is about an air conditioning system that takes advantage of cooling effects by partially or completely converting the fuel into gas phase before directing it to direct combustion cells, thereby converting the fuel energy consumed for the air conditioner compressor to a gain and reducing emissions due to reduced fuel consumption.

Description

C OOLING/AIR C ONDITIONING SY ST E M WITH LIQU E FIE D GAS E S

T E C H NICAL FIE L D

P RIOR ART

In the cooling of the ambient air, the physical events are utilized which are a result of the physical changes of the material. The transition from liquid phase to gas phase is called evaporation, from gas phase to liquid phase called condensation. Under pressure, when the pressure is dropped on the cooling gas, which is in liquid phase, the temperature of the ambient air drops during the transition to the gas phase by absorbing heat (withdrawing) from the ambient. The main physical phenomenon used in the air cooling cycle is the heat extraction from the ambient by the fluids as they pass to the gas phase.

The air conditioning system of a vehicle basically consists of a compressor, a condenser, a moisture trap filter, an expansion valve and an evaporator (heat exchanger).

The operation of an air conditioning system is similar to a domestic refrigerator. By a compressor driven by an internal combustion engine, the refrigerant in the gas phase is compressed and sent to the condenser. The pressure and temperature of the refrigerant sent to the condenser by the compressor increases. In the condenser, the refrigerant is converted to a liquid phase by cooling with air passing between the condenser coils (heat exchangers) which its temperature is lower than the refrigerant. The refrigerant in the high pressure line and passing through the liquid phase is sprayed to the evaporator by reducing its pressure and adjusting its amount through an expansion valve. The heat energy that is pumped by an electric fan and carried by the air passing between the serpentines (heaters / Heat exchangers) passes to the refrigerant contained in the evaporator. The refrigerant passes to the gas phase from the liquid phase by the heat energy it receives. The air passing between the serpentines is cooled by this heat transfer and delivered to the cabin through the vehicle's ventilation system. The refrigerant passing through the gas phase in the evaporator passes to the low pressure line through the expansion valve. The refrigerant in the gas phase in the low pressure line is sucked by the compressor and sent to the condenser under high pressure to be cooled. This cooling process continues in a closed system.

In today's vehicles, R-134a gas is used as refrigerant. The characteristics of the R-134a gas are; its chemical formula is C H2F -C F3, its boiling point is -26.5 eC and its freezing point is -101 .16 eC , its critical temperature is 100.6 e C, its critical pressure is 40.56 bars and its evaporation latent heat is 21 7.2 kj / kg.

In passenger cars, when the engine is idling while the air conditioner is switched on, the fuel consumption increases by approximately 0,5-0,6 It / h. F or example; in 2003 model Opel Vectra 1 ,6 E legance when the engine is idling the fuel consumption is 0.7-0.8 It / h but when the air conditioning system is activated the fuel consumption increases to 1 .3-1 .4 It / h. When the air conditioner is activated, fuel consumption increases by 0.3-0.6 It / h. When the air conditioner is activated for a vehicle that consumes 6 liters of gasoline at 100 km, the fuel consumption increases by 5% with a minimum fuel consumption increase of 0.3 I / h.

E lectricity is generated from gas / steam turbines in processes where natural gas (LNG) cycles are used. E lectricity is generated in the generators while the gas / steam turbines are rotated by the heat energy-bearing fluid obtained by burning the LNG fuel combustion chambers in one of liquid, liquid-gas or gas phases.

LNG is heavily used in industrial and food factories. The cooling work is carried out by compressor air conditioning systems in vehicles with refrigerated transport and C NG conversion system.

B RIE F DE S C RIPTION OF T H E INVE NTION

The invention relates to the cooling of system components in buildings and energy conversion lines in natural gas power generation plants, the cooling of transportation vehicles used in food transportation and the cooling of other areas where liquefied gaseous fuels are heavily used, especially in energy conversion plants (natural gas power generation plants). The present invention further relates to an air conditioning system that reduces emissions due to reduced fuel consumption as the liquefied gaseous fuels are cooled by passing through the gas flare prior to combustion and thereby converting the fuel energy spent for the air conditioner compressor.

MEANINGS OF THE FIGURES

Figure 1. Schematic Description of System Operation with Regulator

Figure 2. Schematic Description of Operation of System with Liquid Fuel Injector

Equivalents of the numbers in the figures are given

1- Liquefied Fuel Tank

2- Multivalve

3- Fuel Filling Port

4- Main E lectrovalve

5- E lectrovalve of the Charge System

6- Regulator

7- E lectrovalve of the Hot Water Circuit

8- Heat Transfer Unit

9- Cooled Ambient

10- Staged Fan

11- E ngine Fuel Cut-Off E lectrovalve

12- Charge Motor Fuel Cut-Off E lectrovalve

13- Temperature/Pressure Sensor

14- Main Motor/Combustion Cell Fuel Injectors

15- Charging Motor

16- E lectricity Generator

17- Staged Fan Selector Switch

18- Liquefied Fuel Pressure Regulator

19- Electronic Fuel Selection Switch

20- E lectronic Control Unit

21- Battery

22- Liquefied Fuel Injector

DETAILED DESCRIPTION OF THE INVENTION

Fuel, which is in the form of liquefied gas under pressure in tanks / stores and fuel delivery pipelines, is like compressed and cooled liquefied refrigerant produced by the compressor in air conditioning systems. Liquefied gas fuels in a fuel tank or in a fuel transport pipeline takes on the function of cooling before the final function (heat generation). Liquefied gas fuels (such as LPG, LNG, C NG, Hydrogen, etc.) in tanks, tubes and pipelines have caused energy consumption when being liquefied. These liquefied fuels are liquid under pressure in the tanks, tubes and pipelines in which they are located.

The working principle of the invention will be explained in this section.

The fuel pumped at high pressure enters the system from the fuel filling port (3). The fuel passing through the inlet valve on the multivalve (2) is stored in the liquefied fuel tank (1 ). Multivalve (2) is a multi-purpose valve which is connected to the liquefied fuel tank (1 ) and controls the level of the liquefied fuel in the tank and its intake and output. Liquefied gaseous fuels will not be sent directly to the combustion chambers in liquid form, as they may cause icing due to their cooling effects. For this reason, the fuel will first be expanded by being passed to the gas phase. The expansion of the fuel is provided in the heat transfer unit (8). The heat transfer unit (8) comprises the regulator (6) and a group of heat exchangers. The diaphragm (6) in the regulator operates under the influence of the spring, atmospheric pressure and vacuum in the intake manifold, to adjust the amount of fuel to enter the unit. The fuel flows from the regulator (6) to the heattransfer section of the unit in the liquid phase. The fuel injection process to the heat transfer unit (8) is carried out with at least one of the parts of the regulator (6) and the liquid fuel injector (22). The injection of fuel to the fuel transfer unit (8) by the liquid fuel injector (22) operating in the control of the electronic control unit (E C U) (20) provides the adjustment of the optimum fuel amount. When the fuel injection process is performed with the liquid fuel injector (22), the electrovalve of the charge system (5), engine fuel cut-off electrovalve (1 1 ) and the regulator (6) will not be used in the system. When the air conditioner is activated, the liquid fuel is expanded by the air circulated in the cooling system and by the engine coolant if the air conditioning system is deactivated. The liquefied fuel required for the operation of the power cycles is delivered to the combustion chambers via the injectors (14) after being expanded in the heat transfer unit (8). The injectors (14) are controlled by the E C U (20). The temperature and pressure of the fuel which is in the gas phase contained in the fuel gallery of the motor is measured by the temperature / pressure sensor (13) and the information is continuously sent to the E C U (20). If the gas pressure rises, the E C U (20) sends information to the liquefied fuel pressure regulator (18). The liquefied fuel pressure regulator (1 8) leaks some gaseous fuel to the intake manifold. In this way, the fuel pressure in the fuel gallery is tried to be kept as stable as possible. When the engine is running, the electrovalve of the charge system (5) and charge motor fuel cut-off electrovalve (12) are switched off. When the engine is not running, the engine fuel cut-off electrovalve (1 1 ) is switched off and the electrovalve of the charge system (5) and the charge motor fuel cut-off electrovalve (12) are switched on for the required cooling. The main electrovalve (4) coming from the tank on the fuel path is always on as long as the systems are running. The fuel vaporized in the heat transfer unit (8) is used for the charging motor (15). The charging motor (1 5) charges the battery (21 ) while feeding the electrical receivers by operating the electricity generator (1 6).

In situations where the cooling system is not used, the engine coolant is circulated in the heat transfer unit (8) to expand the fuel as there is no ambient air circulation. The normally closed electrovalve of the hot water circuit (7) is opened by the E C U (20) to provide this circulation. The flow rate of air circulated in the system is changed by the staged fan (10) motor according to the position of the staged fan selector switch (17). If the temperature and the flow rate of the cooled ambient (9) circulated on the cooling system is low, the hot water cycle is activated by the E C U (20) because of that the liquid fuel cannot completely evaporate in the heat transfer unit (8).

In the processes in which the automatic climate control systems are used, the adjustment of the desired air temperature requires the use of both heat exchangers. Because the main task of the system is to cool down, a heat source is needed to increase the air temperature. The hot water cycle is used to meet this heating requirement. The heat energy needed to vaporize the fuel will be equal to the sum of the heat energy that the heat exchangers give to the system. As the contribution rates of the heat exchangers to the evaporation process in total heat energy can change, the air temperature may also change.

In vehicles using liquefied gaseous fuel, the cooling required when the internal combustion engine is not running is provided using the liquefied gas in the fuel tank. In the energetically maximized utilization principle, the vaporized fuel in the heat transfer unit (8) is converted to electrical energy by the resulting mechanical energy charging system, by being burned in a small single-cylinder motor. S ome of the energy charges the batteries in the vehicle while others supply the staged fan (10) and other electrical receivers. The electronic fuel selection switch (19) informs the E C U (20) about the type of fuel to be used in the system. The electronic fuel selection switch (1 9) is engaged in two or more fuel-operated systems.

Depending on the need for cooling, the cabin / indoor-outdoor air is circulated through the tubular heat exchanger structure located in the heat transfer unit (8) via the staged fan (10).

A vehicle speeds up to 100 km / h per hour consumes between 7 and 10 liters of LPG . If the entire fuel is passed through the cooling system, heat can be absorbed from the environment at a maximum of 3,5 kg LP G x 380 kj / kg at 1330 kj / hr and 5 kg LPG x 380 kJ / kg at 1 900 kj / hr. To reduce the temperature of 1 m³ of air by 22 e C, 27 kj of heat energy from air must be absorbed. The heat absorption is done by the evaporation latent heat of liquefied gases. If a car has a cabin volume of4-6mE it needs to absorb 108 / 1 62kJ of heat energy. This value is the standard value, and when the factors such as the sun, the human and the heat transfer level are incorporated into the work, the heat value to be absorbed exceeds 108 / 1 62kJ . Liquefied gases can easily overcome this job, even if we take 4-5 times the total value of the standard value.

The same cooling system and method can be used in cooling systems of buildings and energy conversion lines in natural gas power gene ration facilities, cooling of transportation vehicles used for food transportation, and other uses where liquefied gaseous fuels are used intensively. Liquefied gas fuels used in energy conversion facilities (natural gas power generation plants) and for industrial production purposes can be used for the cooling function by being passed to the gas phase before the combustion. S ome or all of the fuels such as hydrogen, LP G, LNG and C NG will be evaporated in the heat transfer unit (8) to cool the ambient and superheated system components. In this regard, the increasing use of air conditioning in the summer months will reduce the increased energy need and environmental pollution. C losed sections of food transport vehicles with cooler and freezer characteristics can also be cooled with the use of such liquefied gaseous fuels.

The evaporation latent heat of hydrogen is 904kJ / kg, and the boiling point is - 252,87 e C . F uture use of hydrogen, a fuel of the future, will be increased by liquefaction. According to scientific evidence, 70% of the universe is hydrogen.

Claims

C LAIMS A cooling/air conditioning system with liquefied gases characterized in that comprising a liquefied fuel tank (1 ), a multivalve (2) controls the level of the liquefied fuel in the tank and its intake and output, a fuel filling port (3), a main electrovalve (4), an electrovalve of the charge system (5), a regulator (6), an electrovalve of the hot water circuit (7), a heat transfer unit (8) provides the expansion of the fuel, a cooled ambient (9), a staged fan (10), an engine fuel cut-off electrovalve (1 1 ), a charge motor fuel cut-off electrovalve (12), a temperature / pressure sensor (13) measures the temperature and pressure of the fuel which is in the gas phase contained in the fuel gallery, a multiple of main motor/combustion cell fuel injectors (14), a charging motor (1 5), electricity generator (16), a staged fan selector switch (17), a liquefied fuel pressure regulator (1 8), an electronic fuel selection switch (19) informs an E C U (20) about the type of fuel to be used in the system, the electronic control unit (20), a battery (21 ) and a liquefied fuel injector.