Gas low-temperature heat exchange performance test method

The invention provides a gas low-temperature heat exchange performance test method. The method comprises the following steps: (1) checking airtightness; (2) introducing oxygen into a cooling coil; (3) introducing liquid nitrogen into a cavity, observing an air outlet temperature sensor of the coil, and cooling oxygen to a target temperature; (4) recording a temperature, a pressure and a flow at the current, and recording a liquid level H1 of the liquid nitrogen at the moment; (5) replacing a pipeline with a nitrogen steel cylinder instead of an oxygen steel cylinder; (6) introducing methane into the cooling coil, and adjusting the apertures of a first adjusting valve and a third adjusting valve to stabilize the pressure and flow at target values; (7) repeating the step (3) and the step (4), recording a temperature T2, a pressure P2 and a flow Q2 corresponding to the cooling methane, and recording a liquid level H2 of the liquid nitrogen at the moment. A convective heat transfer method is adopted, so that the problem of large thermal conduction resistance is solved.