Vehicle Cooling Unit Bypass Duct for Fan Pressure Protection
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Solution Overview
Problem
Existing vehicle cooling devices face critical situations when ambient pressure is high, potentially damaging the fan and electronics due to insufficient design, as they are not equipped to handle such pressures effectively.
Innovation Solution
A cooling device with a control unit that adjusts the position of a closure element in a bypass channel based on pressure differences between ambient, inlet, and outlet pressures to manage airflow and reduce pressure differences, thereby preventing the fan from being driven by air flow.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the cooling device uses a standard fan design without bypass channels, then the device complexity is low, but the fan reliability deteriorates under high ambient pressure conditions
Solution Approach 1:
The air channel is segmented into a main channel and a bypass channel, allowing airflow to be divided into two paths: one through the condenser and fan, and another bypassing the fan. This segmentation enables the system to handle high ambient pressure without overloading the fan, thereby improving fan reliability while maintaining manageable device complexity through structured channel division.
Solution Approach 2:
The bypass channel acts as an intermediary pathway that provides an alternative route for airflow around the fan. By introducing this intermediate structure, the system mediates between high ambient pressure conditions and the fan's operational limits, preventing direct exposure of the fan to excessive pressure differentials that would compromise its reliability.
2Productivity
If the closure element remains closed, then the airflow through the fan is maximized for cooling efficiency, but the pressure difference across the fan increases causing harmful effects
Solution Approach 1:
The closure element is designed to be dynamically adjustable rather than fixed, allowing it to transition between closed and open positions based on operating conditions. When ambient pressure is normal, the element remains closed to maximize cooling efficiency. When high pressure is detected, it opens to activate the bypass channel, reducing the pressure difference across the fan and eliminating harmful effects while maintaining adequate cooling performance.
Solution Approach 2:
The system changes the flow resistance parameter by adjusting the closure element's position. In normal conditions, the closure element maintains high flow resistance through the bypass to direct all airflow through the condenser and fan for maximum cooling. Under high ambient pressure, the closure element opens to reduce flow resistance through the bypass, redistributing airflow to reduce the pressure differential across the fan and prevent damage.
3Object-affected harmful factors
If the closure element is opened to bypass airflow, then the pressure difference across the fan is reduced, but the cooling efficiency decreases
Solution Approach 1:
The closure element provides dynamic control over bypass airflow, opening only when necessary to reduce pressure differences under high ambient pressure conditions. This dynamic adjustment ensures that cooling efficiency is maintained at maximum levels during normal operation, while temporarily allowing reduced efficiency during bypass operation only when required to protect the fan from pressure-related damage.
Solution Approach 2:
The bypass channel, which inherently reduces cooling efficiency by diverting airflow away from the condenser, is converted into a protective mechanism. By strategically opening the closure element under high pressure conditions, the system uses the bypass pathway to reduce harmful pressure differences across the fan, transforming what would normally be a efficiency-reducing feature into a damage-prevention mechanism that protects the overall system.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This solution effectively reduces the risk of critical situations by allowing airflow bypass around the fan and condenser, ensuring the fan is not driven by air flow, thus protecting it from damage and maintaining efficient cooling.
Implementation Method 1
a control unit (32) which is configured to control a position of the closure element (22) as a function of a pressure difference between an ambient pressure (p0) applied from the outside at the inlet opening (12) and an outlet pressure (p2) prevailing in the channel (10) in the flow direction after the fan (13) and/or as a function of a pressure difference between an inlet pressure (p1) prevailing in the channel (10) in the flow direction before the condenser (6) and the outlet pressure (p2) prevailing in the channel (10) in the flow direction after the fan (13)
Data Source
Figure 1
Figure 2
AI summary
The invention relates to a cooling unit (2) for a vehicle (36), which has an evaporator (4), a condenser (6), a fan (13) and a duct (10) having an inlet opening (12), wherein a flow direction for air (14) through the duct (10) is specified. The condenser (6) is arranged in the duct (10), and the fan (13) is arranged downstream of the condenser (6) in the flow direction of the air (14). In order to achieve an improved cooling unit (2) for a vehicle (36), by means of which critical situations for the fan (13) are at least reduced, in particular avoided, according to the invention, the cooling unit (2) has a bypass duct (16) which fluidically connects the portion (18) of the duct (10) arranged upstream the condenser (6) in the flow direction of the air (14) to the portion (20) of the duct (10) arranged downstream of the fan (13) in the flow direction of the air (14). Furthermore, according to the invention, the cooling unit (2) has a closure element (22) which is arranged in the bypass duct (16), wherein the closure element (22) is adjustable between an open position and a closed position.