Dual Heat Exchanger HVAC Control for Vehicle Floor Heating
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional vehicular air conditioning systems face challenges in efficiently heating passenger rooms in heating mode, leading to poor heating performance and high energy consumption, which reduces fuel efficiency and comfort.
Innovation Solution
The system incorporates a dual heating heat exchanger configuration with a control part that adjusts the operation of the first and second heating heat exchangers based on passenger room heating load, prioritizing the use of low-power high-efficiency planar heating elements at air discharge ports to directly heat air destined for floor areas.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If the PTC heater is used to compensate for insufficient heat generation, then the heating performance is improved, but the energy consumption increases rapidly
Solution Approach 1:
The heating system is segmented into multiple independent heating heat exchangers (first heating heat exchanger 5 and second heating heat exchangers 20) positioned at different locations. This allows selective operation of specific heating elements based on spatial heating needs, enabling the system to achieve effective heating while minimizing overall energy consumption by activating only the necessary heating zones.
Solution Approach 2:
Different heating heat exchangers are deployed at different locations (air conditioning case and air discharge ports) to provide localized heating where needed. The second heating heat exchangers are specifically positioned at floor-level air discharge ports to directly heat the lower space, addressing the local heating requirement without needing to heat the entire passenger room uniformly, thus reducing energy consumption.
2Area of stationary object
If the air discharge path is extended to reach floor portions, then the heating coverage is improved, but the heat loss increases significantly
Solution Approach 1:
The second heating heat exchangers are installed at the air discharge ports before the air reaches the floor portions. This preliminary heating action ensures that the air is heated at the point of discharge, eliminating the need for long air discharge paths and preventing heat loss during transit. The heating is performed in advance, right where the air is delivered, thus maintaining heating effectiveness while minimizing energy loss.
3Device complexity
If the discharged air temperature is made uniform throughout the passenger room, then the system simplicity is maintained, but the passenger comfort is deteriorated
Solution Approach 1:
The system employs different heating heat exchangers at different locations to create non-uniform temperature distribution. The first heating heat exchanger 5 and second heating heat exchangers 20 are controlled to produce different discharged air temperatures, enabling the cold-head and hot-leg state that enhances passenger comfort. This local differentiation of temperature quality resolves the contradiction by making the system slightly more complex in control but significantly improving comfort.
Solution Approach 2:
The control part dynamically adjusts the operation of different heating heat exchangers based on real-time temperature sensor feedback from various locations in the passenger room. This dynamic control enables the system to maintain optimal temperature differences between upper and lower spaces, adapting to changing conditions while preserving passenger comfort without requiring overly complex manual adjustments.
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 configuration enables efficient and rapid heating of floor areas with minimal energy consumption, improving passenger room comfort and vehicle fuel efficiency by allowing independent temperature control of air discharged to upper and lower spaces.
Implementation Method 1
The heating heat exchanger 5 heats the air introduced into the air inlet and the air is blown into the passenger room along the internal flow path 1a of the air conditioning case 1
Implementation Method 2
The PTC heater 5b generates heat using the electricity applied thereto
Implementation Method 3
a second heating heat exchanger installed at an air discharge port of a vent that discharges air toward a floor in a passenger room
Data Source
AI summary
A vehicular air conditioning system having an air inlet and an air outlet includes a first heating heat exchanger configured to heat air introduced through the air inlet, a second heating heat exchanger configured to heat air passing through the first heating heat exchanger or bypassing the first heating heat exchanger, and a control part configured to control the first heating heat exchanger and the second heating heat exchanger according to a passenger room heating load so that when the heating load decreases to below a preset value in a heating mode in which the first heating heat exchanger and the second heating heat exchanger are operated simultaneously, the first heating heat exchanger is first turned off and only the second heating heat exchanger is operated.