Pin-to-Hole Spark Discharge for Non-Thermal Plasma
Solution Overview
Problem
Existing plasma devices for biomedical applications face challenges with high energy consumption and excessive electrode temperatures, making them unsuitable for certain medical uses, particularly in generating non-thermal plasmas at moderate temperatures for effective tissue treatment.
Innovation Solution
The development of atmospheric pressure pin-to-hole spark discharge devices that utilize a capacitative circuit to create pulsed spark discharges with a gas flow, producing non-thermal plasmas suitable for biomedical applications, including the use of a sharp-tipped positive electrode and a ground plate electrode with a capacitative circuit capable of generating a voltage of at least 500 V, allowing for the emission of non-thermal plasma without the need for a separate cooling system.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If DC arcs are used to generate plasma for biomedical applications, then plasma generation is achieved, but energy consumption becomes high and electrode temperature becomes excessively high
Solution Approach 1:
The patent employs pulsed DC arc discharge instead of continuous DC arc, creating periodic plasma generation cycles. The capacitor charges during off-periods and discharges during on-periods, providing intermittent plasma that reduces cumulative heat buildup in electrodes while maintaining effective plasma generation during active periods. This periodic operation allows thermal management without sacrificing plasma generation capability.
Solution Approach 2:
The capacitor is pre-charged before each plasma discharge event, storing electrical energy in advance. This preliminary energy storage enables rapid, high-power plasma generation when needed, while the energy is delivered in controlled bursts rather than continuous flow. The system prepares the energy reservoir beforehand, allowing efficient energy delivery only when plasma is required.
2Temperature
If active cooling systems are added to plasma devices, then electrode temperature is controlled, but device complexity increases
Solution Approach 1:
The pulsed discharge system inherently manages electrode temperature through its periodic operation cycle. The capacitor discharge duration is limited, and the off-period allows passive thermal dissipation without requiring active cooling infrastructure. The system uses its own operational timing to self-regulate temperature, eliminating the need for separate cooling pumps, heat exchangers, or temperature sensors.
Solution Approach 2:
By operating in pulsed mode with sufficient duty cycle control, the system creates natural thermal management intervals. The periodic nature of capacitor charging and discharging provides built-in cooling periods where electrodes can dissipate heat passively to the environment, maintaining temperature control through operational timing rather than active thermal management systems.
3Temperature
If liquid cooling systems are implemented in plasma generators, then thermal management is improved, but ease of operation deteriorates due to additional maintenance requirements
Solution Approach 1:
The pulsed capacitor discharge system manages its own thermal load through operational timing. The inherent cycle of charging and discharging creates natural thermal management without requiring external cooling infrastructure. This eliminates liquid cooling systems entirely, removing all associated maintenance needs for coolant circulation, filtration, and system monitoring, thereby greatly simplifying operation.
Solution Approach 2:
The invention extracts and eliminates the liquid cooling subsystem from the plasma generation system. By using pulsed discharge with sufficient off-periods for passive cooling, the design removes the entire liquid cooling infrastructure (pumps, pipes, heat exchangers, coolant reservoirs), leaving only the essential plasma generation components that require no thermal management maintenance.
4Temperature
If plasma temperature is reduced for biomedical safety, then tissue damage risk decreases, but plasma generation efficiency worsens
Solution Approach 1:
The system changes the temporal parameters of plasma generation by using pulsed discharge with controlled duty cycles. This allows the plasma to exist at high temperature only during brief discharge intervals, then cool during capacitor recharge periods. The average temperature remains low for tissue safety, while peak temperatures during discharge maintain plasma generation efficiency and reactivity.
Solution Approach 2:
The periodic pulsed discharge creates temporal separation between high-temperature plasma generation and cooling phases. During the discharge phase, efficient high-temperature plasma is generated for effective treatment. During the recharge phase, the plasma cools passively. This time-based strategy maintains both efficiency and safety without requiring compromise in either parameter.
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 enables the generation of cold plasmas that can be safely applied to the human body, effectively treating skin ulcers by restoring blood flow and sterilization without the need for a second electrode, reducing the risk of tissue damage and improving healing processes.
Implementation Method 1
a capacitative circuit capable of creating a pulsed spark discharge at a rate of at least 1 Hz... the capacitative circuit being capable of creating a pulsed spark discharge at a rate of at least 1 Hz in the spark zone
Implementation Method 2
create pulsed spark discharges with a gas flow, producing non-thermal plasmas
Implementation Method 3
flowing a gas through the spark zone simultaneously with the creation of the pulsed spark discharge is capable of giving rise to a non-thermal plasma emitted from the second portion of the conduit
Data Source
AI summary
Disclosed herein are atmospheric pressure pin-to-hole pulsed spark discharge devices and methods for creating plasma. The devices include a conduit for fluidically communicating a gas, a plasma, or both, therethrough, portion of the conduit capable of being connected to a gas supply, and a second portion of the conduit capable of emitting a plasma; a positive electrode comprising a sharp tip; and a ground plate electrode. Disclosed are methods for treating a skin ulcer using non-thermal plasma include flowing a gas through a cold spark discharge zone simultaneously with the creation of a pulsed spark discharge to give rise to a non-thermal plasma emitted from a conduit, the non-thermal plasma comprising NO; and contacting a skin ulcer with said non-thermal plasma for sufficient time and intensity to give rise to treatment of the skin ulcer.