Home » knowledge » Optical fiber temperature sensor for temperature monitoring during microwave heating

Optical fiber temperature sensor for temperature monitoring during microwave heating

Microwave oven (microwave oven/microwave), as the name suggests, is a modern cooking stove that uses microwaves to heat food. Microwaves are an electromagnetic wave. A microwave oven consists of a power supply, a magnetron, a control circuit and a cooking cavity.

Microwave oven (microwave oven/microwave), as the name suggests, is a modern cooking stove that uses microwaves to heat food. Microwaves are an electromagnetic wave. A microwave oven consists of a power supply, a magnetron, a control circuit and a cooking cavity. The power supply provides a high voltage of about 4000 volts to the magnetron, and the magnetron continuously generates microwaves under the excitation of the power supply, which is then coupled into the cooking cavity through the waveguide system. There is a rotatable stirrer near the entrance of the cooking cavity. Because the stirrer is a fan-shaped metal, it reflects microwaves in all directions after being rotated, so the microwave energy can be evenly distributed in the cooking cavity, thereby Heat food. The power range of microwave ovens is generally 500 to 1000 watts.

Optical fiber temperature sensor for temperature monitoring during microwave heating

A microwave oven is a cooking appliance that uses food to absorb microwave energy in a microwave field to heat itself. The microwave generated by the microwave generator in the microwave oven establishes a microwave electric field in the microwave oven cavity, and certain measures are taken to make this microwave electric field distribute as evenly as possible in the oven cavity, and the food is put into the microwave electric field, and the cooking time is controlled by the control center and microwave electric field strength for various cooking processes.

In layman’s terms, microwave is a high-frequency electromagnetic wave that does not generate heat by itself. Microwaves are everywhere in the universe and nature, but there are microwaves in nature. Because they are not scattered and concentrated, they cannot heat food. Microwave ovens use their internal magnetrons to convert electrical energy into microwaves and penetrate food with an oscillation frequency of 2450MHz. When microwaves are absorbed by food, polar molecules (such as water, fat, protein, sugar, etc.) in the food are Attracted to oscillate rapidly at a rate of 2.45 billion times per second, the macroscopic manifestation of this oscillation is that the food is heated.

The principle of microwave heating is simply: when microwaves are radiated to the food, the food always contains a certain amount of water, and water is composed of polar molecules (the positive and negative charge centers of the molecules, even in the absence of an external electric field. coincident), the orientation of such polar molecules will change with the microwave field. Due to this movement of polar molecules of water in food. As well as the interaction between adjacent molecules, a phenomenon similar to friction occurs, which increases the temperature of the water and, therefore, the temperature of the food. The food heated by microwave is heated at the same time, so that the whole object is heated evenly, and the heating speed is also fast. At a frequency of 2.45 billion times per second, it penetrates 5cm deep into the food to heat and accelerate the operation of molecules.

Three taboos for heating food in microwave ovens:

1. Avoid heating the meat to half-cooked before heating it in a microwave oven: because the bacteria will still grow in the half-cooked food, when the second time is heated in a microwave oven, it is impossible to kill all the bacteria due to the short time, and the bacteria will still grow. breeding, which will endanger human health. Frozen meat products must be thawed in the microwave before reheating for cooked food.

2. Avoid re-freezing the meat thawed in the microwave oven: because the meat has been thawed in the microwave oven, the outer layer has actually been heated at a low temperature. At this temperature, bacteria can multiply, although re-freezing can make it multiply Stop, but cannot kill live bacteria. Therefore, meat that has been thawed in the microwave must be heated until fully cooked if it is then frozen in the refrigerator.

3. Avoid fried food: because of the high oil content of fried food, high temperature oil will splash and cause fire. In case of accidental fire in the furnace, do not open the door, but turn off the power first, and then open the door to cool down after the fire is extinguished.

Three things not to use to heat food in the microwave:

1. Do not use ordinary plastic containers: use special microwave oven utensils to hold food and heat it in the microwave oven. First, hot food will deform the plastic container, and second, ordinary plastic will release toxic substances, pollute the food, and endanger human health.

2. Do not use metal utensils: Because of the iron, aluminum, stainless steel, enamel and other utensils placed in the furnace, the microwave oven will generate electric sparks and reflect microwaves when heating, which will damage the furnace body and heat undercooked food.

3. Do not use closed containers: When heating liquids, wide-mouth containers should be used, because the heat generated by heating food in closed containers is not easy to dissipate, which makes the pressure in the container too high, which may easily cause explosion accidents. Even when frying food with a shell, pierce the shell with a needle or chopsticks in advance, so as not to burst after heating, splash and stain the furnace wall, or splash and hurt people.

Optical fiber temperature sensor for temperature monitoring during microwave heating

Finally, a fiber optic sensor for temperature monitoring in the heating process of microwave ovens is introduced, which is the fiber optic temperature sensor introduced by Gongcai. SD and FOT-L-BA are a class of fiber optic temperature sensors that are ideal for measuring temperature in extreme environments, including cryogenics, nuclear environments, microwaves, and high-intensity RF. The FOT-L combines all the good features you would expect from an ideal sensor body. As a result, these sensors provide highly accurate and reliable temperature measurements even in extreme temperatures and adverse environments.

The main features of both FOT-L temperature sensors are their complete immunity to EMI and RFI, their small size, built-in safety features for hazardous environments, high temperature resistance, corrosion resistance and high accuracy. Based on fiber optic technology, the sensor is inherently immune to EMI and RFI. The light sensor is electronically inactive, so it neither emits nor is affected by any type of EM radiation, be it microwave, RF or is NMR.

The Links:   LTM09C012 MEO500-06DA