Fluid analysis method and apparatus

A down hole tool positionable in a well bore having a wall and penetrating a subterranean formation, the formation having a fluid therein, the down hole tool comprising:

• a housing;
• a fluid communication device extendable from the housing for sealing engagement with the wall of the well bore, the fluid communication device having at least one inlet for receiving the fluid from the formation;
• a fluid analysis assembly positioned within the housing for analyzing the fluid, the fluid analysis assembly comprising:
• a chamber defining an evaluation cavity for receiving the fluid from the fluid communication device;
• a fluid movement device having a force medium applying force to the fluid to cause the fluid to move within the evaluation cavity;
• a pressurization assembly changing the pressure of the fluid, wherein the assembly is able to change the pressure independently of the fluid movement device;
• and
• at least one sensor communicating with the fluid for sensing at least one parameter of the fluid.

A method for measuring a parameter of an unknown fluid within a well bore penetrating a formation having the fluid therein, comprising the steps of:

• positioning a fluid communication device of the down hole tool in sealing engagement with a wall of the well bore;
• drawing fluid out of the formation and into an evaluation cavity within the down hole tool;
• moving the fluid within the evaluation cavity wit a fluid movement device;
• changing a pressure of the fluid with a pressurization assembly without changing parameters of the fluid movement device;
• and
• sampling data of the fluid wit a sensor while the fluid is being moved within the evaluation cavity.

A down hole tool positionable in a well bore having a wall and penetrating a subterranean formation, the formation having a fluid therein, the down hole tool comprising:

• a housing;
• a fluid communication device extendable from the housing for sealing engagement with the wall of the well bore, the fluid communication device having at least one inlet for receiving the fluid from the formation;
• a fluid analysis assembly positioned within the housing for analyzing the fluid, the fluid analysis assembly comprising:
• a chamber defining an evaluation cavity configured as a re-circulating loop for receiving the fluid from the fluid communication device;
• a fluid movement device having a force medium applying force to the fluid to cause the fluid to re-circulate within the re-circulating loop;
• a pressurization assembly changing the pressure of the fluid;
• and
• at least one sensor communicating with the fluid for sensing at least one parameter of the fluid.