Portable Field Viscometer Using Falling Needle for In-Service Fluid Analysis
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for determining the viscosity of Newtonian and non-Newtonian fluids are inaccurate, cumbersome, and often require laboratory settings, making it difficult to measure viscosity in the field or under in-service conditions, especially for diesel engine oils, which can lead to costly engine damage due to contamination issues.
Innovation Solution
A portable field viscometer with a disposable or reusable sample insert tube and a needle with guide fins is used to measure the time of fall of the needle through a predetermined distance, allowing for accurate calculation of viscosity, shear rate, and shear stress, and is designed to be simple, portable, and easy to use, eliminating the need for complex equipment and laboratory settings.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional laboratory viscometers are used, then measurement accuracy can be achieved, but portability and ease of field operation are lost
Solution Approach 1:
The patent extracts the core measurement function from complex laboratory viscometers and implements it in a simplified portable device. The falling needle viscometer uses basic gravitational force and timing mechanisms to achieve viscosity measurement without requiring laboratory infrastructure, temperature control systems, or complex calibration apparatus.
Solution Approach 2:
The patent employs disposable sample cells and needles that are inexpensive and single-use. This eliminates the need for expensive, delicate equipment that requires careful maintenance and calibration, enabling field deployment while maintaining measurement quality. The disposable components can be discarded after use, avoiding cleaning and sterilization requirements.
2Measurement precision
If complex laboratory equipment is used, then accurate viscosity measurements can be obtained, but measurement time and operational complexity increase
Solution Approach 1:
The measurement process is segmented into simple, discrete steps: insert the needle, release it to fall, timing the descent, and calculating viscosity. This segmentation eliminates time-consuming procedures such as temperature equilibration, complex calibration sequences, and multi-stage measurement protocols required by traditional viscometers.
Solution Approach 2:
The patent replaces complex mechanical measurement systems with a simple gravitational falling needle mechanism. Instead of using motorized rotors, heated samples, or electronically controlled stress application, the device uses pure gravitational force and optical or magnetic timing to achieve measurements rapidly and accurately.
3Ease of operation
If falling sphere viscometers are used, then viscosity can be measured, but spherical object availability and measurement accuracy are limited
Solution Approach 1:
The patent replaces expensive, precision-manufactured spherical objects with inexpensive, disposable needles of various shapes and densities. These needles can be easily manufactured from common materials and discarded after use, eliminating the need for precision machining while maintaining measurement accuracy through proper design.
Solution Approach 2:
The patent changes the measurement parameter from spherical objects to needle-shaped objects with varying densities and dimensions. By adjusting needle parameters such as length, diameter, and material composition, the device can measure viscosity across a wide range of fluid types and viscosities, overcoming the limitations of fixed-density spherical viscometers.
4Device complexity
If capillary tube viscometers are used, then viscosity measurement is possible, but the method is limited to high shear rates and requires precise dimensional control
Solution Approach 1:
The patent changes the fundamental measurement parameter from pressure-driven flow through capillaries to gravity-driven falling motion. This parameter change enables measurement across a wide range of shear rates by simply adjusting the needle dimensions and fluid column height, whereas capillary viscometers are restricted to high shear rates due to their flow mechanism.
Solution Approach 2:
The falling needle viscometer serves multiple functions: it can measure viscosity of Newtonian and non-Newtonian fluids, operate at various shear rates, and be used with different fluid volumes. The same basic device structure handles diverse measurement requirements by changing needle parameters, whereas capillary viscometers require different apparatus for different shear rate ranges.
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
The portable field viscometer provides accurate viscosity measurements with better than 1% and 2% accuracy, extending engine life and enabling detection of diesel contamination in engine oils, and can be used for various industrial fluids, offering a cost-effective and efficient solution for field applications.
Implementation Method 1
the viscosity is determined from the time taken for a sphere to fall through a predetermined distance in an infinite fluid
Implementation Method 2
Viscosity is a function of internal friction and of the behavior of a fluid under stress
Implementation Method 3
The guide fins on the needle surface may be configured to provide a coaxial concentric descent of the needle through the sampling tube containing the test fluid
Data Source
AI summary
An apparatus and method are disclosed for accurately determining viscosity of Newtonian and non-Newtonian fluids in the field or in-service by using a potable field viscometer. The portable field viscometer includes a vertical disposable (or reusable) sample insert tube filled with the liquid which the viscosity is to be determined. Using fins on the needle surface, a needle having a known density is made to fall through the liquid in the disposable (or reusable) sample insert tube coaxially. Using the time that the needle takes to fall between two known distance marks on the extension bar attached the top of the needle or transducers such as light, laser or magnetic, the velocity of the needle falling through the liquid is determined. Thus, the viscosity can be calculated by using the velocity of a needle. In the method, viscosity, shear rate and shear stress can be determined according to the disclosed method.