viscosity
Viscosity is a word to describe the fluid flow performance of the system.By moving the two fluid layer to make it move relative to generate a friction (stiffness and internal friction), is the resistance to flow.Viscous force is through several layers of fluid at different speeds.This makes faster flow movement slowing, slower motion faster flow layer.These processes comply with the principle of physics, can be defined in equation, the shear rate (velocity gradient) and the shear modulus is a factor.viscosity总是取决于温度，如：粘度测量是通过测定稠度来优化一个类膏状的物质或优化使其适合生产线。
Backward extrusion tooling alternative rotational viscometer
ZwickRoell backward extrusion tooling for rotational viscometer provides an alternative.Backward extrusion tooling principle is based on the measurement in the annular clearance between the piston and backward extrusion device material displacement.Device to fill the test material, the piston to the container, the lower position of the extrusion materials, materials will be upwards through the annular gap, when the piston rises, material flow, back through the annular clearance to enter into the hole.
In the specified location, measuring the force in the up and down cycle.Dynamic viscosity of the assessment is measuring the force difference, and the liquid flow in annular space.
ZwickRoell system can repeat the cycle, and set free shear rate.To optimize the test so as to adapt to the test material, within the scope of the shear, using a single test can measure the viscosity.
The advantage of this method
- Can be directly on the production line of container determination of viscosity.Can be directly on the material for prestressing.By changing the annular clearance and the speed of moving, but now the flow of the production plant.
- This method can be tested for objects with large particles, if the sauce and food system: more pieces of food or other materials will not be extrusion test system, but with yogurt or fluid test.
- Independently choose number of test cycles, and can increase the shear rate of each test cycle, which can be recorded in a test all corresponding viscosity shearing rate.
- Newtonian fluid was determined by rotational viscometer of test results, for non Newtonian fluids, also can get reproducible and can be compared to test results, are usually better than rotary viscosimeter more sensitive properties of the data.
In addition, another advantage) designed for viscosity test testXpert III test program:
This particular test procedure contains multiple extra features designed for viscosity test.Such as: automatic pretreatment and determination of cycle number and speed, choose the results, etc.The test software interface is clear, can be the result of the complex evaluation, and assess the data and graphic display, and generate a report.
