DE102024000438A1 - Air duct, vehicle and method for its operation - Google Patents

Abstract

The invention relates to an air duct (10) for guiding an air flow (L), wherein at least one plasma actuator (1) for influencing the air flow (L) guided in the air duct (10) is arranged in or on the air duct (10). The plasma actuator (1) has two electrodes (2, 5) separated by a dielectric layer (4) and connected to a voltage source (6) for generating an alternating voltage. The invention further relates to a vehicle comprising: a vehicle front (9) with at least one air inlet (11), at least one cooling module (12), and at least one air duct (10) for guiding an air flow (L) between the air inlet (11) and the cooling module (12). The invention further relates to a method for operating a vehicle, wherein a homogeneity and/or air mass of an air flow (L) flowing towards the at least one cooling module (12) is increased by controlling the at least one plasma actuator (1).

Description

The invention relates to an air duct according to the preamble of claim 1, a vehicle according to claim 6 and a method for its operation according to the preamble of claim 7.

The routing of air from the air intake to specific destinations in vehicles, for example to the intercooler or cooling module, can be suboptimal due to space constraints and may, for example, exhibit unfavorable flow paths or diffusive sections with flow separation. The efficiency of the intercooler and/or cooling module is impaired by these inhomogeneities in the air flow. During system design, this is often compensated for by dimensioning the corresponding cooling module larger, which creates additional challenges for the overall vehicle design, airflow, and weight. Likewise, if the air entering the system is not fully utilized, the size of the air intake must be designed accordingly to ensure the necessary air mass flow. This leads to increased driving resistance during operation and thus to higher overall vehicle consumption.

To direct the airflow to cooling modules in the vehicle, the air volume is adjusted as needed via an adjustable air guidance system in the front of the vehicle. Due to the specific installation space, it may be necessary to design the cooling module larger than theoretically necessary. This can be caused by other components blocking the airflow or by an inhomogeneous pressure distribution of the air on the cooling module. Enlarging the cooling module ensures sufficient functionality and performance of the vehicle. Homogenization of the airflow in technical and industrial applications is often achieved through additional air baffles, with the well-known disadvantages: pressure loss, additional components, and no active adjustment.

EP 2 321 084 A1 describes a vortex generator system consisting of one or more plasma vortex generators (PSVGs) or plasma wedge vortex generators (PWVGs). The PSVGs and PWVGs each comprise a first electrode and a second electrode separated by a dielectric layer. The first electrode extends longitudinally. The PSVGs and PWVGs can be installed on a surface arranged to receive airflow in a specific flow direction. The PSVGs have a rectangular first electrode that is exposed and extends at least somewhat parallel to the expected flow direction, while the first electrode of the PWVGs has a more triangular shape. When an alternating voltage is applied to the first and second electrodes, a plasma forms along the edges of the first electrode. The plasma exerts a body force in the cross-flow direction, which induces a cross-flow velocity, which in combination with the flow leads to a homogenization of the air mass flow and thus to a reduction of the flow separation within the air duct.

The invention is based on the object of providing a novel air duct, a novel vehicle and a novel method for its operation.

The object is achieved according to the invention by an air duct having the features of claim 1, by a vehicle having the features of claim 6 and by a method for its operation having the features of claim 7.

Advantageous embodiments of the invention are the subject of the subclaims.

An air duct for guiding an air flow is proposed. According to the invention, at least one plasma actuator is arranged in or on the air duct for influencing the air flow guided in the air duct. The plasma actuator has two electrodes separated by a dielectric layer, which are connected to a voltage source for generating an alternating voltage. The voltage source is connected to the electrodes via cabling and can be arranged separately from the electrodes and the dielectric layer. In this case, only the electrodes and the dielectric layer are arranged directly in or on the air duct.

In one embodiment, the plasma actuator is arranged on a component that impairs a flow cross-section of the air flow or on a bend in the air duct.

In one embodiment, the plasma actuator is arranged flush with a surface of the component or the air duct.

In one embodiment, the voltage source is arranged separately from the electrodes, wherein a wiring for connecting the electrodes to the voltage source is guided through a surface on which the plasma actuator or its electrodes and dielectric layer is/are arranged.

In one embodiment, the voltage source is configured to generate alternating voltages with variable frequency.

• - eine Fahrzeugfront mit mindestens einem Lufteinlass,
• - mindestens ein Kühlmodul, beispielsweise einen Ladeluftkühler oder einen Wärmetauscher einer Klimaanlage, und
• - mindestens einen Luftführungskanal wie oben beschrieben zum Führen einer Luftströmung zwischen dem Lufteinlass und dem Kühlmodul.

According to one aspect of the present invention, a vehicle is proposed comprising:

• - a vehicle front with at least one air intake,
• - at least one cooling module, for example an intercooler or a heat exchanger of an air conditioning system, and
• - at least one air duct as described above for guiding an air flow between the air inlet and the cooling module.

According to one aspect of the present invention, a method for operating the vehicle is proposed, wherein a homogeneity of the inflow and/or the air quantity of the air mass flow onto the cooling module is increased by controlling the at least one plasma actuator.

In one embodiment, the at least one plasma actuator is controlled in a driving situation in which an increased mass flow or an optimized distribution on the cooling module is required.

In one embodiment, the plasma actuator is controlled depending on a current driving situation, a vehicle condition, environmental conditions and/or a driver request, in particular by means of at least one characteristic map.

In one embodiment, the vehicle has sensors, including an air mass meter in the flow cross-section of the front of the vehicle and sensors for detecting the ambient boundary conditions, wherein a dynamic control of the at least one plasma actuator takes place.

The plasma actuator can stabilize the airflow in such a way that sufficient air mass and air distribution is allowed through the cooling module, such as the charge air cooler or the radiator, to ensure functionality and performance, whereby the size of the cooling module can be reduced or the performance can be further increased until components in the powertrain, such as the battery and/or drive units, begin to reduce performance.

The inventive solution increases the homogeneity of the air mass flow at desired locations (e.g., the charge air cooler or the heat exchanger of the heating, ventilation, and air conditioning system), resulting in increased efficiency of the heat exchange process. This can be used to increase vehicle performance and/or vehicle efficiency. Furthermore, the overall size of the heat exchanger can be reduced while maintaining the same level of performance. With the possibility of sharper bends, space constraints during the design process can be reduced. By better utilizing the intake air, the size of the intake opening can be reduced, leading to higher vehicle efficiency by reducing aerodynamic drag. The option to activate the plasma actuator when needed can save energy. For example, the plasma actuator can be deactivated in driving situations where no additional cooling is required (e.g., moderate driving in moderate outside temperatures), thus eliminating the need for additional energy.

The need for activation depends on the driving situation and can occur, for example, when driving under high load, such as on inclines, in high outside temperatures or in environments with low air density/low oxygen content in the air, such as at high altitudes.

The power requirement, frequency and/or voltage can be varied depending on the boundary conditions, such as vehicle speed, air density, air temperature, humidity, the driving situation and/or the vehicle characteristics.

Embodiments of the invention are explained in more detail below with reference to drawings.

• 1 eine schematische Ansicht eines Plasmaaktuators,
• 2 eine schematische Ansicht einer Fahrzeugfront mit einem Luftführungskanal zwischen einem Lufteinlass und einem Kühlmodul sowie mehreren im Luftführungskanal angeordneten Plasmaaktuatoren, und
• 3 eine schematische Ansicht einer Fahrzeugfront mit einem Luftführungskanal zwischen einem Lufteinlass und einem Kühlmodul sowie mehreren am Luftführungskanal angeordneten Plasmaaktuatoren.

Showing:

• 1 a schematic view of a plasma actuator,
• 2 a schematic view of a vehicle front with an air duct between an air inlet and a cooling module as well as several plasma actuators arranged in the air duct, and
• 3 a schematic view of a vehicle front with an air duct between an air inlet and a cooling module as well as several plasma actuators arranged on the air duct.

Corresponding parts are provided with the same reference numerals in all figures.

1 is a schematic view of a plasma actuator 1.

The plasma actuator 1 can be used to optimize the speed and distribution of an air mass flowing onto a cooling module and to reduce flow turbulence.

The plasma actuator 1 has a first electrode 2, which can be applied to a surface of a component 3 (for example, by vapor deposition, gluing, or as an insert into the component 3). A dielectric layer 4 (for example, a coating) is arranged on the first electrode 2. A second electrode 5 is arranged on the dielectric layer 4. The material selected for both electrodes 2, 5 is designed so that the lowest possible currents are required to create the effect. Furthermore, the plasma actuator 1 has a voltage source 6 for generating an alternating voltage and cabling 7 for contacting the voltage source 6 with the electrodes 2, 5. In the energized, active state, the plasma actuator 1 generates a plasma region 8 at the exposed electrode 5 and influences an air flow L in its vicinity. This influence can be achieved in such a way that the homogeneity of the air flow L of a cooling module subjected to air flow and the air mass at the cooling module are increased. This can be implemented both on components that impair the flow cross-section and on a suboptimally designed housing geometry. The electrodes 2, 5 can be arranged parallel to each other to specify a defined actuation direction.

Due to the small space requirement of the plasma actuator 1, it can also be installed in confined spaces, such as those found in vehicle fronts 9 (in 2 shown). For this purpose, the plasma actuator 1 is mounted flush with the corresponding surface in order to have the smallest possible influence on the air flow L due to its shape. The cable is routed through the corresponding component 3 in order to avoid disrupting the air flow L. The voltage source 6 can be placed at a different location. The electromagnetic field generated at the electrodes 2, 5 can have variable frequencies, whereby the shape, size and position of the field can be influenced and thus a further optimization of the air flow L can be achieved.

The advantage of the switchable plasma actuator 1 is that it can be controlled in driving situations where an increased mass flow or optimized distribution on the cooling module is required. This ensures that the energy advantage for cooling and/or air conditioning of the vehicle and/or the drivetrain components provided by the optimized air flow L is not offset by the permanent energy consumption of the plasma actuator 1.

Plasma actuator 1 is controlled based on knowledge of the current driving situation, the ambient conditions, and the driver's input (for example, with a focus on efficient or high-performance driving). Using characteristic maps, an application can be accessed directly, and the necessary electrical energy requirement for plasma actuator 1 can be provided depending on the driving situation and vehicle condition. If the vehicle is equipped with appropriate sensors (in particular, air mass meters in the flow cross-section of the vehicle's front end, ambient conditions), dynamic control of plasma actuators 1 is also possible.

By appropriately mounting and implementing the plasma actuator 1 and applying the software accordingly, the efficiency and performance of vehicles with a main cooling module that is not optimally supplied with air can be improved, depending on the driver's wishes and the vehicle's characteristics.

2 is a schematic view of a vehicle front end 9 with an air duct 10 between an air inlet 11 and a cooling module 12, for example, a charge air cooler or a heat exchanger of an air conditioning system. A component 3 that affects the flow cross-section is arranged in the air duct 10. At least one plasma actuator 1, in particular a plurality of plasma actuators 1, can be arranged on this component 3.

3 is a schematic view of a vehicle front end 9 with an air duct 10 between an air inlet 11 and a cooling module 12, for example, a charge air cooler or a heat exchanger of an air conditioning system. The air duct 10 has sections with sharp bends that can impair the air flow L. At these sections, at least one plasma actuator 1, in particular a plurality of plasma actuators 1, is arranged on the air duct 10, which functions as component 3 (support component).

The vehicle front 9 can be part of a vehicle, in particular a passenger car, a commercial vehicle or a bus.

List of reference symbols

1

Plasma actuator

2

electrode

3

component

4

dielectric layer

5

electrode

6

Voltage source

7

cabling

8

Plasma region

9

Vehicle front

10

Air duct

11 12

Air inlet cooling module

L

Air flow

QUOTES CONTAINED IN THE DESCRIPTION

This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 2 321 084 A1 [0004]

Claims (10)

Air guide channel (10) for guiding an air flow (L), characterized in that at least one plasma actuator (1) for influencing the air flow (L) guided in the air guide channel (10) is arranged in or on the air guide channel (10), wherein the plasma actuator (1) has two electrodes (2, 5) separated by a dielectric layer (4) which are connected to a voltage source (6) for generating an alternating voltage. Air duct (10) to Claim 1 , characterized in that the plasma actuator (1) is arranged on a component (3) which impairs a flow cross-section of the air flow (L) or on a bend in the air duct (10). Air duct (10) to Claim 1 or 2 , characterized in that the plasma actuator (1) is arranged flush on a surface of the component (3) or the air duct (10). Air duct (10) according to one of the preceding claims, characterized in that the voltage source (6) is arranged separately from the electrodes (2, 5), wherein a cabling (7) for connecting the electrodes (2, 5) to the voltage source (6) is guided through a surface on which the plasma actuator (1) is arranged. Air duct (10) according to one of the preceding claims, characterized in that the voltage source (6) is configured to generate alternating voltages with a variable frequency. Vehicle, comprising: - a vehicle front (9) with at least one air inlet (11), - at least one cooling module (12), and - at least one air duct (10) according to one of the preceding claims for guiding an air flow (L) between the air inlet (11) and the cooling module (12). Procedure for operating a vehicle according to Claim 6 , characterized in that a homogeneity and/or air mass of an air flow (L) flowing towards the at least one cooling module (12) is increased by controlling the at least one plasma actuator (1). Procedure according to Claim 7 , characterized in that the at least one plasma actuator (1) is controlled in a driving situation in which an increased mass flow or an optimized distribution on the cooling module (12) is required. Procedure according to Claim 7 or 8 , characterized in that the control of the plasma actuator (1) takes place depending on a current driving situation, a vehicle condition, environmental boundary conditions and/or a driver's request by means of at least one characteristic map. Procedure according to Claim 9 , characterized in that the vehicle has sensors, including an air mass meter in the flow cross-section of the vehicle front (9) and sensors for detecting the ambient boundary conditions, wherein a dynamic control of the at least one plasma actuator (1) takes place.