SAE J3142:2018 pdf free

SAE J3142:2018 pdf free.Thermal Flow Control Valve Nomenclature and Application
The mechanical control valve described in 4.5.1 may be enhanced with the addition of a resistive heating element near the wax element, controlled via software. The typical control strategy for this type of valve is to raise the normal opening temperature of the wax chemistry to an optimal control point for low load combustion efficiency, and then bias the opening temperature to a lower control point for higher loads or ambient temperatures by activating the resistive heating element under these conditions. The heating element warms the wax pellet and drives the valve open with colder surrounding coolant versus the normal operating state. The controlling software typically relies upon an engine coolant temperature sensor,which may be optimally located away from the control valve, and may drive the heater element either with on/off or variable controls. The concept of a mechanically controlled thermal flow control valve with an electronically controlled heating element is ilustrated in Figure 7.
Electronically controlled thermal flow control valves are systems that typically include thermocouples, electronic controllers,and valve bodies with internal electric actuators. These systems provide the benefits of sensing fluid system temperatures in one part of the system and regulating (or re-directing) flow in another part of the system. Also, embedded control algorithms are typically deployed to detect and react to any number of variables that are electronically detected within the system.
The most recent development includes thermal management modules (as shown in Figure 8) capable of providing proportional control to multiple flow control ports with integrated electronics, two DC motors, and two rotary valves. The module replaces the traditional wax element thermostat, allowing temperature to be more precisely controlled by means of a rotary slide valve that enables the ideal temperature window for the engine and transmission to be obtained rapidly. Reacting on the driver’s power demand, the valve immediately supplies the required cooling performance. Due to an advanced calculation model, the coolant temperature stays in a range of ±2 °C.SAE J3142 pdf free download.