Arrangement for ventilating a railway vehicle compartment

Abstract

The invention relates to a system for ventilating a compartment (RA) in a railway vehicle to reduce a potentially harmful concentration of a gas within that compartment (RA). The compartment (RA) of the railway vehicle contains a component (VERFL) that releases a concentration of gas into the compartment (RA) in the event of a leak. A passenger accommodation area (FR) of the railway vehicle is connected to the exterior of the vehicle via a ventilation system, such that fresh air (FRIL) enters the passenger accommodation area (FR), mixes there with the circulating air (UML) present in the passenger accommodation area (FR), and is subsequently distributed as supply air (ZUL) within the passenger accommodation area (FR). The passenger accommodation area (FR) is connected to the compartment (RA) via an air duct (LUFTFL).The air duct is designed in such a way that a portion of the supply air (ZUL) is extracted from the passenger accommodation area (FR) as exhaust air (FOL) and is directed in a unidirectional manner (KLAP) to the compartment (RA) to ensure a specific gas concentration in that location.

Description

[0001] The invention relates to an arrangement for ventilating a space in a rail vehicle in order to reduce a potentially harmful concentration of a gas in that space.

[0002] It is known to ventilate a space in a rail vehicle in a targeted manner in order to reduce a gas concentration present or arising there, which could be dangerous for the rail vehicle, the driver, etc., to a permissible limit value.

[0003] Many application scenarios are conceivable here, some of which are listed below as examples, but not as a limitation: For example, it could be a hydrogen concentration in a compartment of a rail vehicle if the rail vehicle has a hydrogen-based drive; it could also be a gas concentration of battery acid in a compartment of a rail vehicle if the rail vehicle has a battery-powered drive; or it could be a gas concentration of a refrigerant in a compartment of a rail vehicle if the rail vehicle has an air conditioning system or refrigeration unit, etc.

[0004] The refrigerant example is illustrated using the driver's cab (FR) of a rail vehicle as an example, with the help of FIG 3 described in more detail.

[0005] The driver's cab (FR) is cooled by a refrigeration unit based on a so-called "vapor refrigerant process". The refrigeration unit consists of a ring-shaped, interconnected compressor (VERDI), evaporator (VERDA), expansion valve (ENTSP), condenser (VERFL), and refrigerant (KM), which flows through the components in different states of matter via a pipe system.

[0006] The VERDA evaporator is coupled to the FR driver's compartment to extract heat from it. d.h. It is either located in the driver's compartment or it is located externally to the driver's compartment FR and connected to it via an intermediate circuit ZWK, which is designed, for example, as a heat exchanger.

[0007] The driver's cab FR is connected to the environment of the rail vehicle via a ventilation system, so that fresh air FRIL from the environment enters the driver's cab FR and is mixed there with recirculated air UML of the driver's cab FR.

[0008] Preferably, the air supply and mixing are supported by a first fan VENT11, which is located in the driver's compartment FR. Alternatively or additionally, a second fan VENT12 is provided for the same purpose.

[0009] The mixed air is cooled via the coupling with the evaporator VERDA; that is, heat is extracted from the mixed air or supplied to the refrigerant KM with the help of the intermediate circuit ZWK and / or the evaporator VERDA. Through the absorption of heat, the refrigerant KM evaporates and flows from the evaporator VERDA to the compressor VERDI.

[0010] In the compressor VERDI, the gaseous refrigerant KM is raised to a higher pressure and temperature level. The gaseous refrigerant KM then flows from the compressor VERDI to the condenser VERFL, which is located in a separate chamber RA.

[0011] In the condenser VERFL, the gaseous refrigerant KM is condensed. The heat released in this process is transferred to the ambient air of room RA and escapes into the environment of the rail vehicle via an exhaust air vent ABL from room RA.

[0012] For example, the RA compartment is located in the front area of ​​the rail vehicle.

[0013] The liquefied refrigerant KM flows from the condenser VERFL to the expansion valve ENTSP. There, the liquid refrigerant KM is "decompressed", i.e., the pressure is reduced and thus the temperature level of the refrigerant KM is lowered.

[0014] The liquid refrigerant KM then passes from the expansion valve ENTSP to the evaporator VERDA and the described cooling cycle begins again.

[0015] The mixed air cooled in the driver's cab (FR) is called supply air (ZUL) and distributed within the cab. A portion of the supply air (ZUL) is released from the driver's cab (FR) back into the environment via a ventilation system as exhaust air (FOL).

[0016] The RA compartment containing the condenser VERFL is structurally separated from the driver's cab FR and connected to the environment of the rail vehicle via a ventilation system. This ventilation system is designed such that intake air ANSL from the environment is passed over the condenser VERFL and returns to the environment of the rail vehicle as exhaust air ABL.

[0017] This airflow is preferably supported by a first fan, VENT21, located in room RE. Alternatively or additionally, a further fan, VENT22, is provided in room RE for the same purpose.

[0018] Due to operational requirements and specifications, individual components of the refrigeration unit may be located in different places or spaces within the rail vehicle, which may not coincide with either the driver's compartment FR or the space RA.

[0019] It is known that the so-called "HFO-1234yf" is used as a refrigerant in refrigeration systems. In its gaseous state, this refrigerant is a flammable, colorless gas with a faint odor, and consequently has the disadvantage that leakage can occur unnoticed. Furthermore, it forms a persistent, environmentally harmful acid, namely trifluoroacetic acid, in the (air) atmosphere of a room.

[0020] Propane is also known to be used as a refrigerant. It burns cleanly and does not form a persistent acid when it escapes, but it forms a highly explosive mixture with air.

[0021] For a compartment in a rail vehicle where a critical gas concentration may occur, a safety assessment or risk evaluation is required. For a positive risk assessment, it must be ensured that, in the event of minor leaks in components of the refrigeration unit, the average gas concentration in the compartment remains low or below a specified gas concentration level.

[0022] In the described arrangement according to FIG 3 This is achieved by continuously directing large quantities of intake air ANSL through room RA, regardless of whether the chiller is in operation or not.

[0023] A disadvantage of this solution is that components involved in this airflow (e.g. filters, fans, duct components, housing parts, etc.) are subject to continuous operation, which leads to increased wear and tear, contamination and increased maintenance requirements.

[0024] The same applies analogously to any space in a rail vehicle if dangerous gas concentrations could occur in it - for example due to the propulsion system, as described at the beginning.

[0025] From publication DE 10 2010 062 660 A1, it is known to optimize the reliability of electrical and electronic components located in the engine room of a rail vehicle that also has at least one driver's cab by operating the rail vehicle with an air conditioning system designed to generate overpressure in the engine room and to air-condition the at least one driver's cab. The air conditioning system comprises a first air duct for introducing fresh air into the at least one driver's cab and a second air duct for conveying at least a portion of the air introduced into the at least one driver's cab to the engine room.

[0026] It is therefore the object of the present invention to provide an improved arrangement for the ventilation of a space in a rail vehicle in order to reduce a potentially harmful or dangerous gas concentration in this space with minimal effort.

[0027] This problem is solved by the features of claim 1. Advantageous further developments are specified in the dependent claims.

[0028] The invention relates to an arrangement for ventilating a room in a rail vehicle, wherein the rail vehicle additionally has a passenger compartment.

[0029] A driver's cab of the rail vehicle is particularly suitable as a passenger lounge.

[0030] The room to be ventilated contains a component which, in the event of a leak, releases a concentration of gas into that room.

[0031] The passenger compartment is connected to the environment of the rail vehicle via a ventilation system, so that fresh air from the environment enters the passenger compartment, is mixed there with recirculated air present in the passenger compartment and is subsequently distributed as supply air in the passenger compartment.

[0032] The occupancy area is connected to the room via an air duct. The air duct is designed such that a portion of the supply air from the occupancy area is extracted as exhaust air and directed unidirectionally into the room to reduce the gas concentration there or to ensure a predetermined (possibly minimum) gas concentration in that room.

[0033] "Unidirectional" here means that the exhaust air is only directed in one direction, namely from the room where people are present into the room.

[0034] This is preferably achieved with the help of a non-return valve, which is, for example, an integrated part of the air duct.

[0035] According to the invention, the component arranged in the room is part of a refrigeration machine that performs cooling using a cold vapor process and releases a gaseous refrigerant in the event of a leak.

[0036] In a preferred further development, the refrigeration machine performs cooling using a cold vapor process.

[0037] In a preferred embodiment, the refrigeration machine comprises a compressor, an evaporator, an expansion valve, a condenser and the refrigerant as ring-shaped interconnected components, wherein the refrigerant flows through the components in different states of matter via a piping system.

[0038] In a preferred further development, the condenser of the refrigeration machine forms the component located in the room.

[0039] In a preferred further development, other components of the refrigeration machine (the compressor and / or the expansion valve) are also arranged in the room.

[0040] In a preferred training method, the evaporator is also located in the room.

[0041] In a preferred further development, the evaporator is coupled to the passenger room - i.e., the evaporator is at least partially located in the passenger room, or the evaporator is located externally to the passenger room but connected to the passenger room via an intermediate circuit.

[0042] In any case, heat is extracted from the recirculated air mixed with fresh air, and thus from the occupant room, and supplied to the refrigerant of the refrigeration machine, which evaporates due to the heat input.

[0043] In a preferred further development, the ring-shaped interconnected components of the refrigeration machine are designed as follows: that the refrigerant, evaporated by heat absorption, passes in gaseous form from the evaporator to the compressor, that in the compressor the gaseous refrigerant is given an increased pressure and temperature level and passes from the compressor to the condenser, that in the condenser the gaseous refrigerant condenses to release heat to the ambient air of the condenser, that the liquefied refrigerant passes from the condenser to the expansion valve to reduce pressure and lower the temperature level of the refrigerant, and that the liquid refrigerant passes from the expansion valve to the evaporator to start the cooling cycle again.

[0044] In a preferred training room, the room is structurally and / or spatially separated from the staff lounge.

[0045] In a preferred training method, the space is located in the front area of ​​the rail vehicle.

[0046] In a preferred further training, the room is connected to the environment of the rail vehicle via a ventilation system, so that the room is ventilated.

[0047] In a preferred further development, the room's ventilation system is designed in such a way that intake air from the environment is passed over the room's component.

[0048] In a preferred further development, the exhaust air is released into the environment of the rail vehicle either alone or together with the intake air as exhaust air.

[0049] In a preferred further development, the supply of exhaust air to the room is designed as a continuous supply, so that in the case of an inactive ventilation system of the room, the reduction of the gas concentration in the room or the ensuring of the specified gas concentration in this room is guaranteed via the exhaust air.

[0050] In a preferred further development, the ventilation system of the room is designed in such a way that the intake air from the environment is directed via the condenser for heat transfer, so that heat from the coolant is transferred to the intake air via the condenser.

[0051] The present invention achieves minimal ventilation of a space in a rail vehicle using simple means and with minimal effort. This minimal ventilation is sufficient to reduce any critical gas concentration that may be present or develop in this space to a negligible level.

[0052] The present invention supports the use of a flammable refrigerant in a refrigeration unit of a rail vehicle: a space considered critical is ventilated by simple means, regardless of whether a ventilation system provided for this space is operated or not.

[0053] The present invention reduces or eliminates the previously necessary continuous operation of components (e.g. filters, fans, piping components, housing parts, etc.) of the room's ventilation system.

[0054] The present invention ensures that, in the case of small leaks, a significant safety margin between the gas concentration and a lower explosion limit is established and maintained.

[0055] The present invention makes it possible to forgo an explicit risk assessment for a room. This results in cost savings.

[0056] The present invention, in particular the non-return valve and the arrangement of the component considered critical, achieves a decoupling of the passenger compartment or the driver's compartment from the room with respect to gas concentration.

[0057] This provides additional protection for the passenger compartment or driver's compartment against the consequences of a leak in the component of the room.

[0058] In the present invention, the special arrangement of the components of the refrigeration machine prevents the flammable refrigerant from entering the passenger compartment in the event of leaks.

[0059] The present invention enables the sustainable application of an environmentally friendly but flammable refrigerant or simplifies its application.

[0060] The invention is explained in more detail below by way of example with reference to a drawing. The drawing shows: FIG 1 an overview of the arrangement according to the invention using a rail vehicle equipped with a refrigeration unit, FIG 2 with reference to FIG 1 some details of the arrangement according to the invention, and FIG 3 the prior art described in the introduction.

[0061] FIG 1 shows an overview of the arrangement according to the invention using a rail vehicle that has a refrigeration machine.

[0062] The driver's cab (FR) is cooled as a passenger compartment using a refrigeration unit based on a so-called "combustion cold process". The refrigeration unit comprises a compressor (VERDI), an evaporator (VERDA), an expansion valve (ENTSP), a condenser (VERFL), and a refrigerant (KM) connected in a ring configuration. The refrigerant flows through the components in different states of matter via a piping system.

[0063] The VERDA evaporator is coupled to the FR driver's compartment to extract heat from it. d.h. It is either located in the driver's compartment or it is located externally to the driver's compartment FR and connected to it via an intermediate circuit ZWK, which is designed, for example, as a heat exchanger.

[0064] The driver's cab FR is connected to the environment of the rail vehicle via a ventilation system, so that fresh air FRIL from the environment enters the driver's cab FR and is mixed there with recirculated air UML of the driver's cab FR.

[0065] Preferably, the air supply and mixing are supported by a first fan VENT11, which is located in the driver's compartment FR. Alternatively or additionally, a second fan VENT12 is provided for the same purpose.

[0066] The mixed air is cooled via the coupling with the VERDA evaporator, d.h. Heat is extracted from the mixed air via the intermediate circuit ZWK and / or the evaporator VERDA, and / or transferred to the refrigerant KM. This heat absorption causes the refrigerant KM to evaporate, and the coolant then flows from the evaporator VERDA to the compressor VERDI.

[0067] In the compressor VERDI, the gaseous refrigerant KM is raised to a higher pressure and temperature level. The gaseous refrigerant KM then flows from the compressor VERDI to the condenser VERFL, which is located in a separate chamber RA.

[0068] In the condenser VERFL, the gaseous refrigerant KM is condensed. The heat released in this process is transferred to the ambient air of room RA and escapes into the environment of the rail vehicle via an exhaust air vent ABL from room RA.

[0069] For example, the RA compartment is located in the front area of ​​the rail vehicle.

[0070] The liquefied refrigerant KM flows from the condenser VERFL to the expansion valve ENTSP. There, the liquid refrigerant KM is "decompressed", i.e., the pressure is reduced and thus the temperature level of the refrigerant KM is lowered.

[0071] The liquid refrigerant KM then passes from the expansion valve ENTSP to the evaporator VERDA and the described cooling cycle begins again.

[0072] The RA compartment containing the condenser VERFL is structurally separated from the driver's cab FR and connected to the environment of the rail vehicle via a ventilation system. This ventilation system is designed such that intake air ANSL from the environment is passed over the condenser VERFL and returns to the environment of the rail vehicle as exhaust air ABL.

[0073] This airflow is preferably supported by a first fan, VENT21, located in room RE. Alternatively or additionally, a further fan, VENT22, is provided in room RE for the same purpose.

[0074] Due to operational requirements and specifications, individual components of the refrigeration unit may be located in different places or spaces within the rail vehicle, which may not coincide with either the driver's compartment FR or the space RA.

[0075] The mixed air cooled in the driver's cab (FR) is referred to as supply air (ZUL) and distributed within the cab. A portion of the supply air (ZUL) is routed from the driver's cab (FR) to the driver's cab (RA) via an air duct (LUFTFL) as exhaust air (FOL).

[0076] The air duct LUFTFL connects the driver's compartment FR with the room RA as an air duct.

[0077] This air duct LUFTFL is designed in such a way that a portion of the supply air ZUL from the driver's compartment FR is extracted as exhaust air FOL and directed unidirectionally into the room RA in order to reduce any gas concentration that may be present there.

[0078] FIG 2 shows some details of the in FIG 1 arrangement shown according to the invention.

[0079] In the example shown here, the evaporator VERDA is part of the driver's compartment FR, while the components VERDI, VERFL and ENTSP of the refrigeration unit are located inside the space RA.

[0080] Preferably, the mixing of the fresh air FRIL with the recirculated air UML takes place within an air treatment facility LUFTB, which has a duct-shaped system for air distribution.

[0081] Fresh air FRIL is drawn in via a first channel KAN1 of the air treatment system LUFTB, while recirculated air UML is drawn in via a second channel KAN2 of the air treatment system LUFTB.

[0082] The fresh air FRIL and the recirculated air UML are mixed together via a connection of the two channels KAN1 and KAN2 and reach the evaporator VERDA via a third channel KAN3 of the air treatment facility LUFTB and the fan VENT11 located there.

[0083] The evaporator VERDA is located in the third channel KAN3 after the fan VENT11.

[0084] The VERDA evaporator extracts heat from the supplied mixed air or cools it down.

[0085] The cooled air then returns to the driver's cab (FR) as supply air (ZUL) via the third channel (KAN3). Here, the supply air (ZUL) is reheated and returns to the air handling unit (LUTB) as recirculated air (UML).

[0086] Heat is extracted from the coolant KM via the condenser VERFL and is released from the RA chamber into the environment of the rail vehicle via the drain ABL.

[0087] The RA room is preferably located adjacent to the driver's compartment, with only and exclusively the following connections between the driver's compartment FR and the RA room being provided: a first line LEIT1, with which the evaporator VERDA is connected to the compressor VERDI for the circulation of the refrigerant KM, a second line LEIT1, with which the evaporator VERDA is connected to the expansion valve ENTSP for the circulation of the refrigerant KM, and the air duct LUFTFL, through which the exhaust air FOL from the driver's compartment FR enters the room RA.

[0088] The exhaust air FOL is preferably extracted from the driver's compartment FR using a fan VENT13, which is located in the driver's compartment FR.

[0089] In room RA, the exhaust air FOL, possibly together with the intake air ANSL, forms the room air of room RA, which is thus flushed through.

[0090] The purging process carried out by the exhaust air FOL is performed continuously and regardless of whether intake air ANSL enters room RA, whether it only enters room RA in a reduced amount, or whether it does not enter room RA at all.

[0091] Preferably, a non-return valve KLAP is integrated within the air duct LUFTFL. This prevents air containing refrigerant KM from entering the driver's compartment FR from compartment RA under predetermined or unfavorable pressure conditions.

[0092] The described spatial separation of the components of the chiller ensures that any leaks that may occur in the chiller are limited to room RA.

[0093] By supplying the exhaust air FOL to room RA, any air-refrigerant concentration that may be present or arising in this room RA is reduced.

[0094] Lowering the limit ensures a significant safety margin above the lower explosive limit (LEL) for small leaks. For low leakage rates, an explicit risk assessment can then be omitted.

Claims

1. Arrangement for ventilating a rail vehicle, - comprising a compartment (RA) and comprising a passenger accommodation area (FR) both arranged in a rail vehicle, - in which the compartment contains a component (VERFL) which releases a gas concentration into the compartment (RA) in the event of a leak, - in which the passenger accommodation area (FR) is connected to the surroundings of the rail vehicle via a ventilation system such that fresh air (FRIL) passes from the surroundings into the passenger accommodation area (FR), is mixed there with circulating air (UML) present in the passenger accommodation area (FR) and is subsequently distributed as supply air (ZUL) in the passenger accommodation area (FR), - in which the passenger accommodation area (FR) is connected to the compartment (RA) via an air duct (LUFTFL), - in which the air duct is designed in such a way that a portion of the supply air (ZUL) is removed from the passenger accommodation area (FR) as outgoing air (FOL) and is conducted in a unidirectional direction (KLAP) into the compartment (RA) in order to ensure a specified gas concentration there, - in which the component arranged in the compartment (RA) is a constituent part of a refrigeration machine which carries out cooling with the aid of a cold vapour process and which releases a gaseous refrigerant in the event of a leak.

2. Arrangement according to Claim 1, in which the refrigeration machine has, as annularly interconnected components, a compressor (VERDI), an evaporator (VERDA), a tension relief valve (ENTSP), a liquefier (VERFL) and the refrigerant (KM), the refrigerant (KM) flowing through the components in different states of aggregation via a duct system.

3. Arrangement according to Claim 2, in which the refrigeration machine component arranged in the compartment (RA) is the liquefier (VERFL).

4. Arrangement according to Claim 2 or 3, in which further refrigeration machine components arranged in the compartment (RA) are the compressor (VERDI) and / or the tension relief valve (ENTSP).

5. Arrangement according to Claim 2, in which the evaporator (VERDA) is arranged in the compartment (RA).

6. Arrangement according to Claim 2, in which the evaporator (VERDA) is coupled to the passenger accommodation area (FR).

7. Arrangement according to Claim 6, - in which the evaporator (VERDA) is at least partially arranged in the passenger accommodation area (FR) or - in which the evaporator is arranged externally to the passenger accommodation area (FR) and is connected to the passenger accommodation area (FR) via an intermediate circuit (ZWK), - such that heat is extracted from the circulating air (UML), which is mixed with fresh air (FRIL), and therefore from the passenger accommodation area (FR) and supplied to the refrigeration machine refrigerant (KM) which evaporates because of the supply of heat.

8. Arrangement according to Claim 2, in which the annularly interconnected components of the refrigeration machine are configured in such a way - that the coolant (KM) evaporated by the absorption of heat passes in gaseous form from the evaporator (VERDA) to the compressor (VERDI), - that, in the compressor (VERDI), the gaseous refrigerant (KM) is provided with an increased pressure level and temperature level and passes from the compressor (VERDI) to the liquefier (VERFL), - that, in the liquefier (VERFL), the gaseous refrigerant (KM) condenses in order to output heat to air surrounding the liquefier (VERFL), - that the liquefied refrigerant (KM) passes from the liquefier (VERFL) to the tension relief valve (ENTSP) in order to reduce pressure and in order to lower a temperature level of the refrigerant (KM), - that the liquid refrigerant (KM) passes from the tension relief valve (ENTSP) to the evaporator (VERDA) in order to begin the cooling circuit again.

9. Arrangement according to Claim 1, in which the compartment (RA) is structurally and / or spatially separated from the passenger accommodation area (FR).

10. Arrangement according to Claim 1, in which the compartment (RA) is connected to the surroundings of the rail vehicle via a ventilation system so that the compartment (RA) is ventilated.

11. Arrangement according to Claim 10, in which the ventilation system of the compartment (RA) is designed in such a way - that intake air (ANSL) originating from the surroundings is conducted via the component of the compartment (RA), and / or - that the outgoing air (FOL) passes back again either on its own or together with the intake air (ANSL) as exhaust air (ABL) to the surroundings of the rail vehicle.

12. Arrangement according to Claims 10 and 11, in which the supply of the outgoing air (FOL) into the compartment (RA) is designed as a continuous supply such that, when a ventilation system of the compartment (RA) is inactive, the maintaining of the specified gas concentration in the compartment (RA) is ensured via the outgoing air (FOL).

13. Arrangement according to Claims 2 and 11, in which the ventilation system of the compartment (RA) is designed in such a manner that the intake air (ANSL) originating from the surroundings is conducted via the liquefier (VERFL) for heat transfer purposes such that heat from the coolant (KM) is transferred via the liquefier (VERFL) to the intake air (ANSL).

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