Apparatus and methods for estimating a characteristic of a fluid downhole using thermal properties of the fluid

An apparatus for estimating a property of a fluid, comprising:

• a chamber configured to be deployed into a wellbore for holding a fluid extracted from a formation;
• and
• a device including an element that heats the fluid in the chamber to a selected temperature at a selected location during a heating phase and measures the temperature of the fluid substantially at the selected location during a sensing phase that follows the heating phase and at least one additional temperature sensor at a location spaced apart from the selected location configured to take a plurality of temperature measurements of the fluid during the sensing phase;
• and
• a controller that processes the temperatures measurements made at the selected location and the spaced apart location to estimate the property of the fluid.

A wellbore system for estimating a property of interest of a fluid during extraction of the fluid from a formation surrounding a wellbore, comprising:

• a tool configured to be deployed into a wellbore that includes:
• a chamber for receiving the fluid extracted from the formation;
• a heat element that heats the fluid to a selected temperature during a heating period;
• a temperature sensor element that measures the temperature of the fluid during a sensing period that following the heating period, wherein the heat element and the temperature sensor element are a single element;
• at least one additional temperature sensor at a location spaced apart from the selected location that measurements the temperature of the fluid at the spaced apart location during the sensing period;
• a data storage device that stores a model relating to the property of the fluid;
• and
• a processor that utilizes the measurements made by the temperature sensor at the selected location and by the at least one additional temperature sensor at the spaced apart location and the model to estimate the property of interest of the fluid during the extraction of the fluid from the formation.