REFRIGERATION CYCLE DEVICE

• Main Author: YAJIMA, Ryuuzaburou
• Format: Patent
• Language: English; French; German
• Published: 20.09.2023
• Subjects: AIR-CONDITIONING, AIR-HUMIDIFICATION, VENTILATION, USE OF AIRCURRENTS FOR SCREENING; BLASTING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; HEATING; LIGHTING; LIQUEFACTION SOLIDIFICATION OF GASES; MANUFACTURE OR STORAGE OF ICE; MECHANICAL ENGINEERING; RANGES; REFRIGERATION MACHINES, PLANTS OR SYSTEMS; REFRIGERATION OR COOLING; VENTILATING; WEAPONS

Excessive specifications of a cutoff valve of a refrigerant cycle apparatus lead to an increase in manufacturing cost. An air conditioner (1) that circulates a flammable refrigerant in a refrigerant circuit (10) includes a liquid-side cutoff valve (71a) and a gas-side cutoff valve (68a) that are put into a cutoff state when refrigerant leakage is detected to suppress the refrigerant leakage into a predetermined space. In a case where fluid is air at 20°C and a differential pressure between upstream and downstream of each of the liquid-side cutoff valve (71a) and the gas-side cutoff valve (68a) is 1 MPa, a cutoff leakage rate at the liquid-side cutoff valve (71a) in the cutoff state is higher than 300 (cm3/min), and a cutoff leakage rate at the gas-side cutoff valve (68a) in the cutoff state is lower than 300 × R (cm3/min), the cutoff leakage rate being an air leakage rate. Here, R = (ρmd × Vmd × Ad)/(Cr × (2 × ΔPr/ρ1r)0.5 × Av × ρ1rl + Av × (2/(λ + 1))((λ + 1)/2(λ - 1)) × (λ × P1r × ρ1rg)0.5) or R = 1, and R is determined based on at least one of a tolerable average concentration, a leakage height, or the type of the refrigerant.