Heat Evacuation System for Fast CNG and Hydrogen Refueling

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

High pressure refueling of hydrogen and compressed natural gas vehicles often results in tank heating due to compression, leading to reduced vehicle range and increased energy consumption, as existing methods like slow fill rates or precooling are inefficient and energy-intensive.

Innovation Solution

A heat evacuation system that uses an interior tank heat absorber interconnected with an external radiator to radiate absorbed heat from the refueling process into the ambient atmosphere, utilizing the high flow rate of refueling gas to power the cooling system, thus reducing tank heating and enabling faster, more efficient refueling.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If high pressure refueling is used to increase refueling speed, then refueling time is reduced, but tank heating increases leading to reduced vehicle range

Engineering Contradiction:

Improverefueling speedVSAvoidtank temperature

Core Design Contradiction:

ProductivityVSTemperature

Solution Approach 1:

The patent converts the harmful compression heat generated during high-speed refueling into a beneficial cooling effect by circulating the refueling gas through heat exchangers. The gas absorbs heat from the tank during compression, then releases this heat externally, thereby cooling the tank and enabling faster refueling without excessive temperature rise.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

Solution Approach 2:

The patent introduces heat exchangers as intermediary components between the refueling gas flow and the tank. These exchangers mediate the thermal interaction, allowing the gas to cool the tank through controlled heat transfer while maintaining high refueling speeds.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Temperature

If slow fill rate is used to reduce tank heating, then tank temperature is controlled, but refueling time increases

Engineering Contradiction:

Improvetank temperatureVSAvoidrefueling time

Core Design Contradiction:

TemperatureVSLoss of time

Solution Approach 1:

The patent transforms the harmful compression heat into a beneficial cooling mechanism. By circulating the gas through heat exchangers, the system uses the heat that would otherwise raise tank temperature to actively cool the tank, enabling slow fill rates to be replaced with fast fill rates without thermal problems.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

3Temperature

If precooling is applied to reduce tank heating, then tank temperature is controlled, but energy consumption increases

Engineering Contradiction:

Improvetank temperatureVSAvoidenergy consumption

Core Design Contradiction:

TemperatureVSUse of energy by moving object

Solution Approach 1:

The patent makes the system self-cooling by using the refueling gas itself as the cooling medium. The gas absorbs heat from the tank during compression and carries this heat to external heat exchangers, eliminating the need for external precooling systems and reducing overall energy consumption.

Inventive Principle:

Principle #25Self-service

Solution Approach 2:

The patent converts the harmful compression heat into a beneficial cooling effect. Instead of requiring external energy input for precooling, the system uses the heat generated during refueling to drive the cooling process through heat exchanger circulation.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

4Quantity of substance

If pressure overfill is used to achieve full tank capacity, then tank capacity is maximized, but energy expense for compression increases

Engineering Contradiction:

Improvetank capacityVSAvoidcompression energy

Core Design Contradiction:

Quantity of substanceVSUse of energy by moving object

Solution Approach 1:

The patent converts the harmful compression heat into a beneficial cooling effect that enables full tank capacity to be achieved without excessive energy expense. The heat exchanger system manages thermal effects during compression, allowing efficient filling to maximum capacity.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

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 reduces energy and time required for refueling, increases vehicle range by maintaining optimal tank pressure, and eliminates the need for slow fill rates or precooling, enhancing overall refueling efficiency and customer satisfaction.

Implementation Method 1

the interior of the on board tanks, namely, the gas itself, becomes heated as a result of gas compression as the tank pressure increases

Methodology Applied

Scientific EffectCompression heating: Adiabatic Heating

Implementation Method 2

radiates the absorbed heat into the ambient atmosphere

Methodology Applied

Scientific EffectThermal radiation: Thermal Radiation

Data Source

PatentUS7757726B2System for enhancing the efficiency of high pressure storage tanks for compressed natural gas or hydrogen

Publication Date: 2010.07.20 HONDA MOTOR CO LTD

AI summary

A system for reducing the energy and for reducing the time required to refill on board tanks on a vehicle from a high pressure fuel depot refilling line operatively interconnected to the tank wherein the refuel gas itself is circulated within the on board tank to absorb the compression heat of refueling, and the heat thereby absorbed is radiated from the refueling circuit to an external environment such that a close to optimum refill of the tank is achieved without the need for a slow fill, precooling or pressure overfill.